fixes

This fixes several cases of the Nim binding of nfds_t being inconsistent
with the target platform signedness and/or size.

Additionally, it fixes poll's third argument (timeout) being set to Nim
"int" when it should have been "cint".

The former is the same issue that #23045 had attempted to fix, but
failed because it only considered Linux. (Also, it was only applied to
version 2.0, so the two branches now have incompatible versions of the
same bug.)

Notes:

* SVR4's original "unsigned long" definition is cloned by Linux and
Haiku. Nim got this right for Haiku and Linux-amd64, but it was wrong on
non-amd64 Linux.
* Zephyr does not have nfds_t, but simply uses (signed) "int". This was
already correctly reflected by Nim.
* OpenBSD poll.h uses "unsigned int", and other BSD derivatives follow
suit. This being the most commonly copied definition, the fallback case
now returns cuint. (This also seems to be correct for the OS X headers I
could find on the web.)
* This changes Nintendo Switch nfds_t to cuint from culong. It is
purportedly a FreeBSD derivative, so I *think* this is correct, but I
can't tell because I don't have access to the Nintendo Switch headers.

I have also moved the platform-specific Tnfds to posix.nim so that we
can reuse the fallback logic on all platforms. (e.g. specifying the size
in posix_linux_amd64 only to then use when defined(linux) in posix_other
seems redundant.)

.github/ISSUE_TEMPLATE/bug_report.yml

@@ -7,17 +7,16 @@ body:
 - type: markdown
   attributes:
     value: |
-      - **Please provide a minimal code example that reproduces the Bug!** :bug:
-        Reports with a reproducible example and descriptive detailed information will likely receive fixes faster.
+      Please provide a minimal code example that reproduces the bug if possible.
+      Reports with a reproducible example or detailed information will likely receive fixes faster.
 
 - type: textarea
   id: description
   attributes:
     label: Description
     description: |
-      Use DETAILED DESCRIPTIVE information about the problem.
-      Here, you go into more details about your Bug report. This section can be a few paragraphs long.
-    placeholder: Bug reports with reproducible code and detailed information will be fixed faster.
+      Describe the problem. Code example can be given here.
+    placeholder: Bug reports with reproducible code or detailed information will be fixed faster.
   validations:
     required: true
     
@@ -25,7 +24,9 @@ body:
   id: nim-version
   attributes:
     label: Nim Version
-    description: Copy and paste the output of `nim -v` on the command line. For development versions, make sure to include the commit hash.
+    description: |
+      Can be obtained from `nim -v` on the command line along with the OS/architecture.
+      For development versions, make sure to include the commit hash.
   validations:
     required: true
 
@@ -34,7 +35,7 @@ body:
   attributes:
     label: Current Output
     description: Please copy and paste any relevant log output. This will be automatically formatted into code, so no need for backticks.
-    placeholder: Bug reports with reproducible code and detailed information will be fixed faster.
+    placeholder: Bug reports with reproducible code or detailed information will be fixed faster.
     render: text
 
 - type: textarea
@@ -42,14 +43,14 @@ body:
   attributes:
     label: Expected Output
     description: Please copy and paste any relevant log output. This will be automatically formatted into code, so no need for backticks.
-    placeholder: Bug reports with reproducible code and detailed information will be fixed faster.
+    placeholder: Bug reports with reproducible code or detailed information will be fixed faster.
     render: text
 
 - type: textarea
-  id: possible-solution
+  id: known-workarounds
   attributes:
-    label: Possible Solution
-    description: Propose a possible solution.
+    label: Known Workarounds
+    description: Provide any known workarounds.
   validations:
     required: false
 
@@ -64,12 +65,9 @@ body:
 - type: markdown
   attributes:
     value: |
-      - Thanks for your contributions!, your Bug report will receive feedback from the community soon...
-      - Please check whether the problem still exists in the devel branch, see [rebuilding the compiler](https://nim-lang.github.io/Nim/intern.html#rebuilding-the-compiler).
+      - Please check whether the problem still exists in the devel branch, which can be installed via [choosenim](https://github.com/nim-lang/choosenim/), [nightlies](https://github.com/nim-lang/nightlies/), or by [creating a temporary build of the compiler](https://nim-lang.github.io/Nim/intern.html#debugging-the-compiler-building-an-instrumented-compiler).
       - Consider writing a PR targetting devel branch after filing this, see [contributing](https://nim-lang.github.io/Nim/contributing.html).
-      - If it's a pre-existing compiler bug, see [Debugging the compiler](https://nim-lang.github.io/Nim/intern.html#debugging-the-compiler)
-        which should give more context on a compiler crash.
-      - If it's a regression, you can help us by identifying which version introduced the bug,
-        see [Bisecting for regressions](https://nim-lang.github.io/Nim/intern.html#bisecting-for-regressions),
-        or at least try known past releases (eg `choosenim 1.2.0`).
+      - If it's a pre-existing compiler bug, see [debugging the compiler](https://nim-lang.github.io/Nim/intern.html#debugging-the-compiler) which should give more context on a compiler crash.
+      - If it's a regression, you can help us by identifying which version introduced the bug by [bisecting](https://nim-lang.github.io/Nim/intern.html#bisecting-for-regressions) or at least trying known past releases (e.g. `choosenim 2.0.0`).
+        The Nim repo also supports bisecting in issue comments by adding `!nim c`, `!nim js` etc. before a code block, see [nimrun-action](https://github.com/juancarlospaco/nimrun-action).
       - [Please, consider a Donation for the Nim project.](https://nim-lang.org/donate.html)

.github/workflows/bisects.yml

@@ -5,19 +5,27 @@ on:
     types: created
 
 jobs:
-  test:
-    runs-on: ubuntu-latest
+  bisects:
+    if: |
+      github.event_name == 'issue_comment' && startsWith(github.event.comment.body, '!nim ') && github.event.issue.pull_request == null && github.event.comment.author_association != 'NONE'
+    strategy:
+      fail-fast: false
+      matrix:
+        platform: [ubuntu-latest, windows-latest, macos-latest]
+    name: ${{ matrix.platform }}-bisects
+    runs-on: ${{ matrix.platform }}
     steps:
-    - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
-    # nimrun-action requires Nim installed.
-    - uses: jiro4989/setup-nim-action@v1
-      with:
-        nim-version: 'devel'
+      - uses: jiro4989/setup-nim-action@v1
+        with:
+          nim-version: 'devel'
 
-    - name: Install Dependencies
-      run: sudo apt-get install --no-install-recommends -yq valgrind
-
-    - uses: juancarlospaco/nimrun-action@nim
-      with:
-        github-token: ${{ secrets.GITHUB_TOKEN }}
+      - uses: juancarlospaco/nimrun-action@nim
+        if: |
+          runner.os == 'Linux'   && contains(github.event.comment.body, '-d:linux'  ) ||
+          runner.os == 'Windows' && contains(github.event.comment.body, '-d:windows') ||
+          runner.os == 'macOS'   && contains(github.event.comment.body, '-d:osx'    ) ||
+          runner.os == 'Linux' && !contains(github.event.comment.body, '-d:linux') && !contains(github.event.comment.body, '-d:windows') && !contains(github.event.comment.body, '-d:osx')
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}

.github/workflows/ci_bench.yml

@@ -1,115 +0,0 @@
-name: Benchmarks CI
-on:
-  pull_request:
-  push:
-    branches:
-      - 'devel'
-
-jobs:
-  build:
-    strategy:
-      fail-fast: false
-      matrix:
-        os: [ubuntu-20.04]
-        cpu: [amd64]
-    name: '${{ matrix.os }}'
-    runs-on: ${{ matrix.os }}
-    timeout-minutes: 60 # refs bug #18178
-    steps:
-      - name: 'Checkout'
-        uses: actions/checkout@v3
-        with:
-          fetch-depth: 2
-
-      - name: 'Install node.js 20.x'
-        uses: actions/setup-node@v4
-        with:
-          node-version: '20.x'
-
-      - name: 'Install dependencies (Linux amd64)'
-        if: runner.os == 'Linux' && matrix.cpu == 'amd64'
-        run: |
-          sudo apt-fast update -qq
-          DEBIAN_FRONTEND='noninteractive' \
-            sudo apt-fast install --no-install-recommends -yq \
-              libcurl4-openssl-dev libgc-dev libsdl1.2-dev libsfml-dev \
-              valgrind libc6-dbg libblas-dev xorg-dev
-
-      - name: 'Add build binaries to PATH'
-        shell: bash
-        run: echo "${{ github.workspace }}/bin" >> "${GITHUB_PATH}"
-
-      - name: 'Build csourcesAny'
-        shell: bash
-        run: . ci/funs.sh && nimBuildCsourcesIfNeeded CC=gcc ucpu='${{ matrix.cpu }}'
-
-      - name: 'Build koch'
-        shell: bash
-        run: nim c koch
-
-      - name: 'Build Nim'
-        shell: bash
-        run: ./koch boot -d:release -d:nimStrictMode --lib:lib
-
-      - name: 'Build Nimble'
-        shell: bash
-        run: ./koch nimble
-
-      - name: 'Action'
-        shell: bash
-        run: nim c -r -d:release ci/action.nim
-
-      - name: 'Checkout minimize'
-        uses: actions/checkout@v3
-        with:
-          repository: 'nim-lang/ci_bench'
-          path: minimize
-
-      - name: 'Run minimize benchmarks'
-        shell: bash
-        run: ./minimize/minimize ci-bench
-
-      - name: 'Restore minimize cached database'
-        uses: actions/cache/restore@v3
-        with:
-          path: minimize.csv
-          key: minimize-db-key
-
-      - name: 'Update minimize db'
-        shell: bash
-        run: ./minimize/minimize update-db
-
-      - name: 'Save minimize cached database'
-        if: |
-          github.event_name == 'push' && github.ref == 'refs/heads/devel' &&
-          matrix.target == 'linux'
-        uses: actions/cache/save@v3
-        with:
-          path: minimize.csv
-          key: minimize-db-key
-
-      - name: 'Generate minimize report'
-        shell: bash
-        run: ./minimize/minimize generate-report
-
-      - name: 'Archive minimize report'
-        uses: actions/upload-artifact@v3
-        with:
-          name: minimize-report
-          path: |
-            minimize/minimize.html
-            minimize/minimize.csv
-
-      # Requires additional permissions, see:
-      # https://github.com/nim-lang/Nim/actions/runs/4778177321/jobs/8494423792?pr=21566
-      # - name: 'Publish HTML report'
-      #   uses: rossjrw/pr-preview-action@v1
-      #   with:
-      #     source-dir: minimize
-      #     umbrella-dir: minimize
-      #   env:
-      #     GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-
-      - name: Extract md summary
-        run: |
-          cat minimize/summary.md  >> $GITHUB_STEP_SUMMARY

.github/workflows/ci_docs.yml

@@ -2,8 +2,7 @@ name: Nim Docs CI
 on:
   push:
     paths:
-      - 'compiler/docgen.nim'
-      - 'compiler/renderverbatim.nim'
+      - 'compiler/**.nim'
       - 'config/nimdoc.cfg'
       - 'doc/**.rst'
       - 'doc/**.md'
@@ -18,8 +17,7 @@ on:
   pull_request:
     # Run only on changes on these files.
     paths:
-      - 'compiler/docgen.nim'
-      - 'compiler/renderverbatim.nim'
+      - 'compiler/**.nim'
       - 'config/nimdoc.cfg'
       - 'doc/**.rst'
       - 'doc/**.md'
@@ -47,7 +45,7 @@ jobs:
           - target: windows
             os: windows-2019
           - target: osx
-            os: macos-12
+            os: macos-13
 
     name: ${{ matrix.target }}
     runs-on: ${{ matrix.os }}
@@ -55,7 +53,7 @@ jobs:
 
     steps:
       - name: 'Checkout'
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           fetch-depth: 2
 
@@ -111,7 +109,7 @@ jobs:
         if: |
           github.event_name == 'push' && github.ref == 'refs/heads/devel' &&
           matrix.target == 'linux'
-        uses: crazy-max/ghaction-github-pages@v3
+        uses: crazy-max/ghaction-github-pages@v4
         with:
           build_dir: doc/html
         env:

.github/workflows/ci_gcc14.yml

@@ -0,0 +1,76 @@
+name: GCC 14
+on:
+  pull_request:
+  push:
+    branches:
+      - 'devel'
+
+
+jobs:
+  build:
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-24.04]
+        cpu: [amd64]
+    name: '${{ matrix.os }}'
+    runs-on: ${{ matrix.os }}
+    timeout-minutes: 60 # refs bug #18178
+    steps:
+      - name: 'Checkout'
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 2
+
+      - name: 'Install node.js 20.x'
+        uses: actions/setup-node@v4
+        with:
+          node-version: '20.x'
+
+      - name: 'Install dependencies (Linux amd64)'
+        if: runner.os == 'Linux' && matrix.cpu == 'amd64'
+        run: |
+          sudo apt update -qq
+          sudo apt remove needrestart
+          DEBIAN_FRONTEND='noninteractive' \
+            sudo apt install --no-install-recommends -yq \
+              libcurl4-openssl-dev libgc-dev libsdl1.2-dev libsfml-dev \
+              valgrind libc6-dbg libblas-dev xorg-dev
+      - name: 'Install dependencies (Linux amd64 gcc 14)'
+        if: runner.os == 'Linux' && matrix.cpu == 'amd64'
+        run: |
+          sudo add-apt-repository universe
+          sudo apt update -qq
+          sudo apt install -y gcc-14 g++-14 libpcre3 liblapack-dev
+          sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-14 60 --slave /usr/bin/g++ g++ /usr/bin/g++-14
+      - name: 'Install dependencies (macOS)'
+        if: runner.os == 'macOS'
+        run: brew install boehmgc make sfml gtk+3
+      - name: 'Install dependencies (Windows)'
+        if: runner.os == 'Windows'
+        shell: bash
+        run: |
+          set -e
+          . ci/funs.sh
+          nimInternalInstallDepsWindows
+          echo_run echo "${{ github.workspace }}/dist/mingw64/bin" >> "${GITHUB_PATH}"
+
+      - name: 'Add build binaries to PATH'
+        shell: bash
+        run: echo "${{ github.workspace }}/bin" >> "${GITHUB_PATH}"
+
+      - name: 'NIM_TESTAMENT_DISABLE_SSL'
+        shell: bash
+        run: echo "NIM_TESTAMENT_DISABLE_SSL=1" >> $GITHUB_ENV
+
+      - name: 'System information'
+        shell: bash
+        run: . ci/funs.sh && nimCiSystemInfo
+
+      - name: 'Build csourcesAny'
+        shell: bash
+        run: . ci/funs.sh && nimBuildCsourcesIfNeeded CC=gcc ucpu='${{ matrix.cpu }}'
+
+      - name: 'koch, Run CI'
+        shell: bash
+        run: . ci/funs.sh && nimInternalBuildKochAndRunCI

.github/workflows/ci_packages.yml

@@ -17,7 +17,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-20.04, macos-12]
+        os: [ubuntu-20.04, macos-13]
         cpu: [amd64]
         batch: ["allowed_failures", "0_3", "1_3", "2_3"] # list of `index_num`
     name: '${{ matrix.os }} (batch: ${{ matrix.batch }})'
@@ -28,7 +28,7 @@ jobs:
       NIM_TESTAMENT_BATCH: ${{ matrix.batch }}
     steps:
       - name: 'Checkout'
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           fetch-depth: 2
 
@@ -48,6 +48,7 @@ jobs:
       - name: 'Install dependencies (macOS)'
         if: runner.os == 'macOS'
         run: brew install boehmgc make sfml gtk+3
+        # XXX can't find boehm and gtk on macos 13
       - name: 'Install dependencies (Windows)'
         if: runner.os == 'Windows'
         shell: bash

.github/workflows/ci_publish.yml

@@ -17,7 +17,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     steps:
       - name: 'Checkout'
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           fetch-depth: 2
 
@@ -71,7 +71,7 @@ jobs:
         run: nim c -r -d:release ci/action.nim
 
       - name: 'Comment'
-        uses: actions/github-script@v6
+        uses: actions/github-script@v7
         with:
           script: |
             const fs = require('fs');

.github/workflows/stale.yml

@@ -9,7 +9,7 @@ jobs:
   stale:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/stale@v8
+      - uses: actions/stale@v9
         with:
           days-before-pr-stale:    365
           days-before-pr-close:    30

azure-pipelines.yml

@@ -29,10 +29,10 @@ jobs:
 #         vmImage: 'ubuntu-18.04'
 #         CPU: i386
       OSX_amd64:
-        vmImage: 'macOS-12'
+        vmImage: 'macOS-13'
         CPU: amd64
       OSX_amd64_cpp:
-        vmImage: 'macOS-12'
+        vmImage: 'macOS-13'
         CPU: amd64
         NIM_COMPILE_TO_CPP: true
       Windows_amd64_batch0_3:
@@ -73,8 +73,8 @@ jobs:
 
     - task: NodeTool@0
       inputs:
-        versionSpec: '16.x'
-      displayName: 'Install node.js 16.x'
+        versionSpec: '20.x'
+      displayName: 'Install node.js 20.x'
       condition: and(succeeded(), eq(variables['skipci'], 'false'))
 
     - bash: |
@@ -130,6 +130,7 @@ jobs:
     - bash: brew install boehmgc make sfml
       displayName: 'Install dependencies (OSX)'
       condition: and(succeeded(), eq(variables['skipci'], 'false'), eq(variables['Agent.OS'], 'Darwin'))
+      # XXX can't find boehm on macos 13
 
     - bash: |
         set -e

build_all.bat

@@ -24,6 +24,6 @@ if not exist %nim_csources% (
   cd ..
   copy /y bin\nim.exe  %nim_csources%
 )
- bin\nim.exe c --noNimblePath --skipUserCfg --skipParentCfg --hints:off koch
- koch boot -d:release --skipUserCfg --skipParentCfg --hints:off
- koch tools --skipUserCfg --skipParentCfg --hints:off
+bin\nim.exe c --noNimblePath --skipUserCfg --skipParentCfg --hints:off koch
+koch boot -d:release --skipUserCfg --skipParentCfg --hints:off
+koch tools --skipUserCfg --skipParentCfg --hints:off

changelog.md

@@ -1,71 +1,33 @@
-# v2.2.0 - yyyy-mm-dd
+# v2.x.x - yyyy-mm-dd
 
 
 ## Changes affecting backward compatibility
 
+- `-d:nimPreviewFloatRoundtrip` becomes the default. `system.addFloat` and `system.$` now can produce string representations of
+floating point numbers that are minimal in size and possess round-trip and correct
+rounding guarantees (via the
+[Dragonbox](https://raw.githubusercontent.com/jk-jeon/dragonbox/master/other_files/Dragonbox.pdf) algorithm). Use `-d:nimLegacySprintf` to emulate old behaviors.
+
+- The `default` parameter of `tables.getOrDefault` has been renamed to `def` to
+  avoid conflicts with `system.default`, so named argument usage for this
+  parameter like `getOrDefault(..., default = ...)` will have to be changed.
 
 ## Standard library additions and changes
 
-[//]: # "Changes:"
-
-
 [//]: # "Additions:"
+- `setutils.symmetricDifference` along with its operator version
+  `` setutils.`-+-` `` and in-place version `setutils.toggle` have been added
+  to more efficiently calculate the symmetric difference of bitsets.
 
-- Added `newStringUninit` to system, which creates a new string of length `len` like `newString` but with uninitialized content.
-- Added `setLenUninit` to system, which doesn't initalize
-slots when enlarging a sequence.
-- Added `hasDefaultValue` to `std/typetraits` to check if a type has a valid default value.
-- Added Viewport API for the JavaScript targets in the `dom` module.
-
-[//]: # "Deprecations:"
-
-
-[//]: # "Removals:"
-
+[//]: # "Changes:"
+- `std/math` The `^` symbol now supports floating-point as exponent in addition to the Natural type.
 
 ## Language changes
 
 
-
-- An experimental option `genericsOpenSym` has been added to allow captured
-  symbols in generic routine bodies to be replaced by symbols injected locally
-  by templates/macros at instantiation time. `bind` may be used to keep the
-  captured symbols over the injected ones regardless of enabling the option.
-
-  Since this change may affect runtime behavior, the experimental switch
-  `genericsOpenSym` needs to be enabled, and a warning is given in the case
-  where an injected symbol would replace a captured symbol not bound by `bind`
-  and the experimental switch isn't enabled.
-
-  ```nim
-  const value = "captured"
-  template foo(x: int, body: untyped) =
-    let value {.inject.} = "injected"
-    body
-
-  proc old[T](): string =
-    foo(123):
-      return value # warning: a new `value` has been injected, use `bind` or turn on `experimental:genericsOpenSym`
-  echo old[int]() # "captured"
-
-  {.experimental: "genericsOpenSym".}
-
-  proc bar[T](): string =
-    foo(123):
-      return value
-  assert bar[int]() == "injected" # previously it would be "captured"
-
-  proc baz[T](): string =
-    bind value
-    foo(123):
-      return value
-  assert baz[int]() == "captured"
-  ```
-
 ## Compiler changes
 
 
 ## Tool changes
 
-- koch now allows bootstrapping with `-d:nimHasLibFFI`, replacing the older option of building the compiler directly w/ the `libffi` nimble package in tow.
 

changelogs/changelog_2_0_0_details.md

@@ -205,7 +205,7 @@
   proc prc(): int =
     123
 
-  iterator iter(): int =
+  iterator iter(): int {.closure.} =
     yield 123
 
   proc takesProc[T: proc](x: T) = discard

changelogs/changelog_2_2_0.md

@@ -0,0 +1,248 @@
+# v2.2.0 - 2024-10-02
+
+
+## Changes affecting backward compatibility
+
+- `-d:nimStrictDelete` becomes the default. An index error is produced when the index passed to `system.delete` is out of bounds. Use `-d:nimAuditDelete` to mimic the old behavior for backward compatibility.
+
+- The default user-agent in `std/httpclient` has been changed to `Nim-httpclient/<version>` instead of `Nim httpclient/<version>` which was incorrect according to the HTTP spec.
+
+- Methods now support implementations based on a VTable by using `--experimental:vtables`. Methods are then confined to the same module where their type has been defined.
+
+- With `-d:nimPreviewNonVarDestructor`, non-var destructors become the default.
+
+- A bug where tuple unpacking assignment with a longer tuple on the RHS than the LHS was allowed has been fixed, i.e. code like:
+  ```nim
+  var a, b: int
+  (a, b) = (1, 2, 3, 4)
+  ```
+  will no longer compile.
+
+- `internalNew` is removed from the `system` module, use `new` instead.
+
+- `bindMethod` in `std/jsffi` is deprecated, don't use it with closures.
+
+- The JS backend now supports lambda lifting for closures. Use `--legacy:jsNoLambdaLifting` to emulate old behaviors.
+
+- The JS backend now supports closure iterators.
+
+- `owner` in `std/macros` is deprecated.
+
+- Ambiguous type symbols in generic procs and templates now generate symchoice nodes.
+  Previously; in templates they would error immediately at the template definition,
+  and in generic procs a type symbol would arbitrarily be captured, losing the
+  information of the other symbols. This means that generic code can now give
+  errors for ambiguous type symbols, and macros operating on generic proc AST
+  may encounter symchoice nodes instead of the arbitrarily resolved type symbol nodes.
+
+- Partial generic instantiation of routines is no longer allowed. Previously
+  it compiled in niche situations due to bugs in the compiler.
+
+  ```nim
+  proc foo[T, U](x: T, y: U) = echo (x, y)
+  proc foo[T, U](x: var T, y: U) = echo "var ", (x, y)
+
+  proc bar[T]() =
+    foo[float](1, "abc")
+
+  bar[int]() # before: (1.0, "abc"), now: type mismatch, missing generic parameter
+  ```
+
+- `const` values now open a new scope for each constant, meaning symbols
+  declared in them can no longer be used outside or in the value of
+  other constants.
+
+  ```nim
+  const foo = (var a = 1; a)
+  const bar = a # error
+  let baz = a # error
+  ```
+
+- The following POSIX wrappers have had their types changed from signed to
+  unsigned types on OSX and FreeBSD/OpenBSD to correct codegen errors:
+  - `Gid` (was `int32`, is now `uint32`)
+  - `Uid` (was `int32`, is now `uint32`)
+  - `Dev` (was `int32`, is now `uint32` on FreeBSD)
+  - `Nlink` (was `int16`, is now `uint32` on OpenBSD and `uint16` on OSX/other BSD)
+  - `sin6_flowinfo` and `sin6_scope_id` fields of `Sockaddr_in6`
+    (were `int32`, are now `uint32`)
+  - `n_net` field of `Tnetent` (was `int32`, is now `uint32`)
+
+- The `Atomic[T]` type on C++ now uses C11 primitives by default instead of
+  `std::atomic`. To use `std::atomic` instead, `-d:nimUseCppAtomics` can be defined.
+
+
+
+
+
+
+## Standard library additions and changes
+
+[//]: # "Changes:"
+
+- Changed `std/osfiles.copyFile` to allow specifying `bufferSize` instead of a hard-coded one.
+- Changed `std/osfiles.copyFile` to use `POSIX_FADV_SEQUENTIAL` hints for kernel-level aggressive sequential read-aheads.
+- `std/htmlparser` has been moved to a nimble package, use `nimble` or `atlas` to install it.
+- Changed `std/os.copyDir` and `copyDirWithPermissions` to allow skipping special "file" objects like FIFOs, device files, etc on Unix by specifying a `skipSpecial` parameter.
+
+[//]: # "Additions:"
+
+- Added `newStringUninit` to the `system` module, which creates a new string of length `len` like `newString` but with uninitialized content.
+- Added `setLenUninit` to the `system` module, which doesn't initialize
+slots when enlarging a sequence.
+- Added `hasDefaultValue` to `std/typetraits` to check if a type has a valid default value.
+- Added `rangeBase` to `std/typetraits` to obtain the base type of a range type or
+  convert a value with a range type to its base type.
+- Added Viewport API for the JavaScript targets in the `dom` module.
+- Added `toSinglyLinkedRing` and `toDoublyLinkedRing` to `std/lists` to convert from `openArray`s.
+- ORC: To be enabled via `nimOrcStats` there is a new API called `GC_orcStats` that can be used to query how many
+  objects the cyclic collector did free. If the number is zero that is a strong indicator that you can use `--mm:arc`
+  instead of `--mm:orc`.
+- A `$` template is provided for `Path` in `std/paths`.
+- `std/hashes.hash(x:string)` changed to produce a 64-bit string `Hash` (based
+on Google's Farm Hash) which is also often faster than the present one.  Define
+`nimStringHash2` to get the old values back.  `--jsbigint=off` mode always only
+produces the old values.  This may impact your automated tests if they depend
+on hash order in some obvious or indirect way.  Using `sorted` or `OrderedTable`
+is often an easy workaround.
+
+[//]: # "Deprecations:"
+
+- Deprecates `system.newSeqUninitialized`, which is replaced by `newSeqUninit`.
+
+[//]: # "Removals:"
+
+
+
+
+
+
+## Language changes
+
+- `noInit` can be used in types and fields to disable member initializers in the C++ backend.
+
+- C++ custom constructors initializers see https://nim-lang.org/docs/manual_experimental.html#constructor-initializer
+
+- `member` can be used to attach a procedure to a C++ type.
+
+- Inside a C++ constructor, `result` can be used to access the created object rather than `this`.
+
+- Tuple unpacking changes:
+  - Tuple unpacking assignment now supports using underscores to discard values.
+    ```nim
+    var a, c: int
+    (a, _, c) = (1, 2, 3)
+    ```
+  - Tuple unpacking variable declarations now support type annotations, but
+    only for the entire tuple.
+    ```nim
+    let (a, b): (int, int) = (1, 2)
+    let (a, (b, c)): (byte, (float, cstring)) = (1, (2, "abc"))
+    ```
+
+- The experimental option `--experimental:openSym` has been added to allow
+  captured symbols in generic routine and template bodies respectively to be
+  replaced by symbols injected locally by templates/macros at instantiation
+  time. `bind` may be used to keep the captured symbols over the injected ones
+  regardless of enabling the option, but other methods like renaming the
+  captured symbols should be used instead so that the code is not affected by
+  context changes.
+
+  Since this change may affect runtime behavior, the experimental switch
+  `openSym` needs to be enabled; and a warning is given in the case where an
+  injected symbol would replace a captured symbol not bound by `bind` and
+  the experimental switch isn't enabled.
+
+  ```nim
+  const value = "captured"
+  template foo(x: int, body: untyped): untyped =
+    let value {.inject.} = "injected"
+    body
+
+  proc old[T](): string =
+    foo(123):
+      return value # warning: a new `value` has been injected, use `bind` or turn on `experimental:openSym`
+  echo old[int]() # "captured"
+
+  template oldTempl(): string =
+    block:
+      foo(123):
+        value # warning: a new `value` has been injected, use `bind` or turn on `experimental:openSym`
+  echo oldTempl() # "captured"
+
+  {.experimental: "openSym".}
+
+  proc bar[T](): string =
+    foo(123):
+      return value
+  assert bar[int]() == "injected" # previously it would be "captured"
+
+  proc baz[T](): string =
+    bind value
+    foo(123):
+      return value
+  assert baz[int]() == "captured"
+
+  template barTempl(): string =
+    block:
+      foo(123):
+        value
+  assert barTempl() == "injected" # previously it would be "captured"
+
+  template bazTempl(): string =
+    bind value
+    block:
+      foo(123):
+        value
+  assert bazTempl() == "captured"
+  ```
+
+  This option also generates a new node kind `nnkOpenSym` which contains
+  exactly 1 `nnkSym` node. In the future this might be merged with a slightly
+  modified `nnkOpenSymChoice` node but macros that want to support the
+  experimental feature should still handle `nnkOpenSym`, as the node kind would
+  simply not be generated as opposed to being removed.
+
+  Another experimental switch `genericsOpenSym` exists that enables this behavior
+  at instantiation time, meaning templates etc can enable it specifically when
+  they are being called. However this does not generate `nnkOpenSym` nodes
+  (unless the other switch is enabled) and so doesn't reflect the regular
+  behavior of the switch.
+
+  ```nim
+  const value = "captured"
+  template foo(x: int, body: untyped): untyped =
+    let value {.inject.} = "injected"
+    {.push experimental: "genericsOpenSym".}
+    body
+    {.pop.}
+
+  proc bar[T](): string =
+    foo(123):
+      return value
+  echo bar[int]() # "injected"
+
+  template barTempl(): string =
+    block:
+      var res: string
+      foo(123):
+        res = value
+      res
+  assert barTempl() == "injected"
+  ```
+
+
+
+
+
+## Compiler changes
+
+- `--nimcache` using a relative path as the argument in a config file is now relative to the config file instead of the current directory.
+
+
+
+
+
+## Tool changes
+
+- koch now allows bootstrapping with `-d:nimHasLibFFI`, replacing the older option of building the compiler directly w/ the `libffi` nimble package.

changelogs/changelog_X_XX_X.md

@@ -1,4 +1,4 @@
-# v1.xx.x - yyyy-mm-dd
+# v2.xx.x - yyyy-mm-dd
 
 This is an example file.
 The changes should go to changelog.md!

ci/action.nim

@@ -3,7 +3,7 @@ import std/[strutils, os, osproc, parseutils, strformat]
 
 proc main() =
   var msg = ""
-  const cmd = "./koch boot --gc:orc -d:release"
+  const cmd = "./koch boot --mm:orc -d:release"
 
   let (output, exitCode) = execCmdEx(cmd)
 

compiler/aliasanalysis.nim

@@ -74,7 +74,7 @@ proc aliases*(obj, field: PNode): AliasKind =
   # x[i] -> x[i]: maybe; Further analysis could make this return true when i is a runtime-constant
   # x[i] -> x[j]: maybe; also returns maybe if only one of i or j is a compiletime-constant
   template collectImportantNodes(result, n) =
-    var result: seq[PNode]
+    var result: seq[PNode] = @[]
     var n = n
     while true:
       case n.kind

compiler/aliases.nim

@@ -10,7 +10,9 @@
 ## Simple alias analysis for the HLO and the code generators.
 
 import
-  ast, astalgo, types, trees, intsets
+  ast, astalgo, types, trees
+
+import std/intsets
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
@@ -49,14 +51,16 @@ proc isPartOfAux(a, b: PType, marker: var IntSet): TAnalysisResult =
   if compareTypes(a, b, dcEqIgnoreDistinct): return arYes
   case a.kind
   of tyObject:
-    if a[0] != nil:
-      result = isPartOfAux(a[0].skipTypes(skipPtrs), b, marker)
+    if a.baseClass != nil:
+      result = isPartOfAux(a.baseClass.skipTypes(skipPtrs), b, marker)
     if result == arNo: result = isPartOfAux(a.n, b, marker)
   of tyGenericInst, tyDistinct, tyAlias, tySink:
-    result = isPartOfAux(lastSon(a), b, marker)
-  of tyArray, tySet, tyTuple:
-    for i in 0..<a.len:
-      result = isPartOfAux(a[i], b, marker)
+    result = isPartOfAux(skipModifier(a), b, marker)
+  of tySet, tyArray:
+    result = isPartOfAux(a.elementType, b, marker)
+  of tyTuple:
+    for aa in a.kids:
+      result = isPartOfAux(aa, b, marker)
       if result == arYes: return
   else: discard
 
@@ -114,6 +118,8 @@ proc isPartOf*(a, b: PNode): TAnalysisResult =
         # use expensive type check:
         if isPartOf(a.sym.typ, b.sym.typ) != arNo:
           result = arMaybe
+        else:
+          result = arNo
     of nkBracketExpr:
       result = isPartOf(a[0], b[0])
       if a.len >= 2 and b.len >= 2:
@@ -149,7 +155,7 @@ proc isPartOf*(a, b: PNode): TAnalysisResult =
       result = isPartOf(a[1], b[1])
     of nkObjUpConv, nkObjDownConv, nkCheckedFieldExpr:
       result = isPartOf(a[0], b[0])
-    else: discard
+    else: result = arNo
     # Calls return a new location, so a default of ``arNo`` is fine.
   else:
     # go down recursively; this is quite demanding:
@@ -165,6 +171,7 @@ proc isPartOf*(a, b: PNode): TAnalysisResult =
 
     of DerefKinds:
       # a* !<| b[] iff
+      result = arNo
       if isPartOf(a.typ, b.typ) != arNo:
         result = isPartOf(a, b[0])
         if result == arNo: result = arMaybe
@@ -186,7 +193,9 @@ proc isPartOf*(a, b: PNode): TAnalysisResult =
         if isPartOf(a.typ, b.typ) != arNo:
           result = isPartOf(a[0], b)
           if result == arNo: result = arMaybe
-      else: discard
+        else:
+          result = arNo
+      else: result = arNo
     of nkObjConstr:
       result = arNo
       for i in 1..<b.len:
@@ -204,4 +213,6 @@ proc isPartOf*(a, b: PNode): TAnalysisResult =
     of nkBracket:
       if b.len > 0:
         result = isPartOf(a, b[0])
-    else: discard
+      else:
+        result = arNo
+    else: result = arNo

compiler/astalgo.nim

@@ -12,23 +12,18 @@
 # the data structures here are used in various places of the compiler.
 
 import
-  ast, hashes, intsets, options, lineinfos, ropes, idents, rodutils,
+  ast, astyaml, options, lineinfos, idents, rodutils,
   msgs
 
-import strutils except addf
+import std/[hashes, intsets]
+import std/strutils except addf
+
+export astyaml.treeToYaml, astyaml.typeToYaml, astyaml.symToYaml, astyaml.lineInfoToStr
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
 
 proc hashNode*(p: RootRef): Hash
-proc treeToYaml*(conf: ConfigRef; n: PNode, indent: int = 0, maxRecDepth: int = - 1): Rope
-  # Convert a tree into its YAML representation; this is used by the
-  # YAML code generator and it is invaluable for debugging purposes.
-  # If maxRecDepht <> -1 then it won't print the whole graph.
-proc typeToYaml*(conf: ConfigRef; n: PType, indent: int = 0, maxRecDepth: int = - 1): Rope
-proc symToYaml*(conf: ConfigRef; n: PSym, indent: int = 0, maxRecDepth: int = - 1): Rope
-proc lineInfoToStr*(conf: ConfigRef; info: TLineInfo): Rope
-
 
 # these are for debugging only: They are not really deprecated, but I want
 # the warning so that release versions do not contain debugging statements:
@@ -36,15 +31,6 @@ proc debug*(n: PSym; conf: ConfigRef = nil) {.exportc: "debugSym", deprecated.}
 proc debug*(n: PType; conf: ConfigRef = nil) {.exportc: "debugType", deprecated.}
 proc debug*(n: PNode; conf: ConfigRef = nil) {.exportc: "debugNode", deprecated.}
 
-proc typekinds*(t: PType) {.deprecated.} =
-  var t = t
-  var s = ""
-  while t != nil and t.len > 0:
-    s.add $t.kind
-    s.add " "
-    t = t.lastSon
-  echo s
-
 template debug*(x: PSym|PType|PNode) {.deprecated.} =
   when compiles(c.config):
     debug(c.config, x)
@@ -79,16 +65,6 @@ template mdbg*: bool {.deprecated.} =
   else:
     error()
 
-# --------------------------- ident tables ----------------------------------
-proc idTableGet*(t: TIdTable, key: PIdObj): RootRef
-proc idTableGet*(t: TIdTable, key: int): RootRef
-proc idTablePut*(t: var TIdTable, key: PIdObj, val: RootRef)
-proc idTableHasObjectAsKey*(t: TIdTable, key: PIdObj): bool
-  # checks if `t` contains the `key` (compared by the pointer value, not only
-  # `key`'s id)
-proc idNodeTableGet*(t: TIdNodeTable, key: PIdObj): PNode
-proc idNodeTablePut*(t: var TIdNodeTable, key: PIdObj, val: PNode)
-
 # ---------------------------------------------------------------------------
 
 proc lookupInRecord*(n: PNode, field: PIdent): PSym
@@ -109,7 +85,7 @@ type
     data*: TIIPairSeq
 
 
-proc initIiTable*(x: var TIITable)
+proc initIITable*(x: var TIITable)
 proc iiTableGet*(t: TIITable, key: int): int
 proc iiTablePut*(t: var TIITable, key, val: int)
 
@@ -197,6 +173,7 @@ proc getSymFromList*(list: PNode, ident: PIdent, start: int = 0): PSym =
   result = nil
 
 proc sameIgnoreBacktickGensymInfo(a, b: string): bool =
+  result = false
   if a[0] != b[0]: return false
   var alen = a.len - 1
   while alen > 0 and a[alen] != '`': dec(alen)
@@ -226,10 +203,11 @@ proc getNamedParamFromList*(list: PNode, ident: PIdent): PSym =
   ## Named parameters are special because a named parameter can be
   ## gensym'ed and then they have '\`<number>' suffix that we need to
   ## ignore, see compiler / evaltempl.nim, snippet:
-  ##   ```
+  ##   ```nim
   ##   result.add newIdentNode(getIdent(c.ic, x.name.s & "\`gensym" & $x.id),
   ##            if c.instLines: actual.info else: templ.info)
   ##   ```
+  result = nil
   for i in 1..<list.len:
     let it = list[i].sym
     if it.name.id == ident.id or
@@ -242,169 +220,7 @@ proc mustRehash(length, counter: int): bool =
   assert(length > counter)
   result = (length * 2 < counter * 3) or (length - counter < 4)
 
-proc rspaces(x: int): Rope =
-  # returns x spaces
-  result = rope(spaces(x))
-
-proc toYamlChar(c: char): string =
-  case c
-  of '\0'..'\x1F', '\x7F'..'\xFF': result = "\\u" & strutils.toHex(ord(c), 4)
-  of '\'', '\"', '\\': result = '\\' & c
-  else: result = $c
-
-proc makeYamlString*(s: string): Rope =
-  # We have to split long strings into many ropes. Otherwise
-  # this could trigger InternalError(111). See the ropes module for
-  # further information.
-  const MaxLineLength = 64
-  result = ""
-  var res = "\""
-  for i in 0..<s.len:
-    if (i + 1) mod MaxLineLength == 0:
-      res.add('\"')
-      res.add("\n")
-      result.add(rope(res))
-      res = "\""              # reset
-    res.add(toYamlChar(s[i]))
-  res.add('\"')
-  result.add(rope(res))
-
-proc flagsToStr[T](flags: set[T]): Rope =
-  if flags == {}:
-    result = rope("[]")
-  else:
-    result = ""
-    for x in items(flags):
-      if result != "": result.add(", ")
-      result.add(makeYamlString($x))
-    result = "[" & result & "]"
-
-proc lineInfoToStr(conf: ConfigRef; info: TLineInfo): Rope =
-  result = "[$1, $2, $3]" % [makeYamlString(toFilename(conf, info)),
-                             rope(toLinenumber(info)),
-                             rope(toColumn(info))]
-
-proc treeToYamlAux(conf: ConfigRef; n: PNode, marker: var IntSet,
-                   indent, maxRecDepth: int): Rope
-proc symToYamlAux(conf: ConfigRef; n: PSym, marker: var IntSet,
-                  indent, maxRecDepth: int): Rope
-proc typeToYamlAux(conf: ConfigRef; n: PType, marker: var IntSet,
-                   indent, maxRecDepth: int): Rope
-
-proc symToYamlAux(conf: ConfigRef; n: PSym, marker: var IntSet, indent: int,
-                  maxRecDepth: int): Rope =
-  if n == nil:
-    result = rope("null")
-  elif containsOrIncl(marker, n.id):
-    result = "\"$1\"" % [rope(n.name.s)]
-  else:
-    var ast = treeToYamlAux(conf, n.ast, marker, indent + 2, maxRecDepth - 1)
-                                 #rope("typ"), typeToYamlAux(conf, n.typ, marker,
-                                 #  indent + 2, maxRecDepth - 1),
-    let istr = rspaces(indent + 2)
-    result = rope("{")
-    result.addf("$N$1\"kind\": $2", [istr, makeYamlString($n.kind)])
-    result.addf("$N$1\"name\": $2", [istr, makeYamlString(n.name.s)])
-    result.addf("$N$1\"typ\": $2", [istr, typeToYamlAux(conf, n.typ, marker, indent + 2, maxRecDepth - 1)])
-    if conf != nil:
-      # if we don't pass the config, we probably don't care about the line info
-      result.addf("$N$1\"info\": $2", [istr, lineInfoToStr(conf, n.info)])
-    if card(n.flags) > 0:
-      result.addf("$N$1\"flags\": $2", [istr, flagsToStr(n.flags)])
-    result.addf("$N$1\"magic\": $2", [istr, makeYamlString($n.magic)])
-    result.addf("$N$1\"ast\": $2", [istr, ast])
-    result.addf("$N$1\"options\": $2", [istr, flagsToStr(n.options)])
-    result.addf("$N$1\"position\": $2", [istr, rope(n.position)])
-    result.addf("$N$1\"k\": $2", [istr, makeYamlString($n.loc.k)])
-    result.addf("$N$1\"storage\": $2", [istr, makeYamlString($n.loc.storage)])
-    if card(n.loc.flags) > 0:
-      result.addf("$N$1\"flags\": $2", [istr, makeYamlString($n.loc.flags)])
-    result.addf("$N$1\"r\": $2", [istr, n.loc.r])
-    result.addf("$N$1\"lode\": $2", [istr, treeToYamlAux(conf, n.loc.lode, marker, indent + 2, maxRecDepth - 1)])
-    result.addf("$N$1}", [rspaces(indent)])
-
-proc typeToYamlAux(conf: ConfigRef; n: PType, marker: var IntSet, indent: int,
-                   maxRecDepth: int): Rope =
-  var sonsRope: Rope
-  if n == nil:
-    sonsRope = rope("null")
-  elif containsOrIncl(marker, n.id):
-    sonsRope = "\"$1 @$2\"" % [rope($n.kind), rope(
-        strutils.toHex(cast[int](n), sizeof(n) * 2))]
-  else:
-    if n.len > 0:
-      sonsRope = rope("[")
-      for i in 0..<n.len:
-        if i > 0: sonsRope.add(",")
-        sonsRope.addf("$N$1$2", [rspaces(indent + 4), typeToYamlAux(conf, n[i],
-            marker, indent + 4, maxRecDepth - 1)])
-      sonsRope.addf("$N$1]", [rspaces(indent + 2)])
-    else:
-      sonsRope = rope("null")
-
-    let istr = rspaces(indent + 2)
-    result = rope("{")
-    result.addf("$N$1\"kind\": $2", [istr, makeYamlString($n.kind)])
-    result.addf("$N$1\"sym\": $2",  [istr, symToYamlAux(conf, n.sym, marker, indent + 2, maxRecDepth - 1)])
-    result.addf("$N$1\"n\": $2",     [istr, treeToYamlAux(conf, n.n, marker, indent + 2, maxRecDepth - 1)])
-    if card(n.flags) > 0:
-      result.addf("$N$1\"flags\": $2", [istr, flagsToStr(n.flags)])
-    result.addf("$N$1\"callconv\": $2", [istr, makeYamlString($n.callConv)])
-    result.addf("$N$1\"size\": $2", [istr, rope(n.size)])
-    result.addf("$N$1\"align\": $2", [istr, rope(n.align)])
-    result.addf("$N$1\"sons\": $2", [istr, sonsRope])
-
-proc treeToYamlAux(conf: ConfigRef; n: PNode, marker: var IntSet, indent: int,
-                   maxRecDepth: int): Rope =
-  if n == nil:
-    result = rope("null")
-  else:
-    var istr = rspaces(indent + 2)
-    result = "{$N$1\"kind\": $2" % [istr, makeYamlString($n.kind)]
-    if maxRecDepth != 0:
-      if conf != nil:
-        result.addf(",$N$1\"info\": $2", [istr, lineInfoToStr(conf, n.info)])
-      case n.kind
-      of nkCharLit..nkInt64Lit:
-        result.addf(",$N$1\"intVal\": $2", [istr, rope(n.intVal)])
-      of nkFloatLit, nkFloat32Lit, nkFloat64Lit:
-        result.addf(",$N$1\"floatVal\": $2",
-            [istr, rope(n.floatVal.toStrMaxPrecision)])
-      of nkStrLit..nkTripleStrLit:
-        result.addf(",$N$1\"strVal\": $2", [istr, makeYamlString(n.strVal)])
-      of nkSym:
-        result.addf(",$N$1\"sym\": $2",
-             [istr, symToYamlAux(conf, n.sym, marker, indent + 2, maxRecDepth)])
-      of nkIdent:
-        if n.ident != nil:
-          result.addf(",$N$1\"ident\": $2", [istr, makeYamlString(n.ident.s)])
-        else:
-          result.addf(",$N$1\"ident\": null", [istr])
-      else:
-        if n.len > 0:
-          result.addf(",$N$1\"sons\": [", [istr])
-          for i in 0..<n.len:
-            if i > 0: result.add(",")
-            result.addf("$N$1$2", [rspaces(indent + 4), treeToYamlAux(conf, n[i],
-                marker, indent + 4, maxRecDepth - 1)])
-          result.addf("$N$1]", [istr])
-      result.addf(",$N$1\"typ\": $2",
-           [istr, typeToYamlAux(conf, n.typ, marker, indent + 2, maxRecDepth)])
-    result.addf("$N$1}", [rspaces(indent)])
-
-proc treeToYaml(conf: ConfigRef; n: PNode, indent: int = 0, maxRecDepth: int = - 1): Rope =
-  var marker = initIntSet()
-  result = treeToYamlAux(conf, n, marker, indent, maxRecDepth)
-
-proc typeToYaml(conf: ConfigRef; n: PType, indent: int = 0, maxRecDepth: int = - 1): Rope =
-  var marker = initIntSet()
-  result = typeToYamlAux(conf, n, marker, indent, maxRecDepth)
-
-proc symToYaml(conf: ConfigRef; n: PSym, indent: int = 0, maxRecDepth: int = - 1): Rope =
-  var marker = initIntSet()
-  result = symToYamlAux(conf, n, marker, indent, maxRecDepth)
-
-import tables
+import std/tables
 
 const backrefStyle = "\e[90m"
 const enumStyle = "\e[34m"
@@ -568,14 +384,12 @@ proc value(this: var DebugPrinter; value: PType) =
     this.key "n"
     this.value value.n
 
-  if value.len > 0:
-    this.key "sons"
-    this.openBracket
-    for i in 0..<value.len:
-      this.value value[i]
-      if i != value.len - 1:
-        this.comma
-    this.closeBracket
+  this.key "sons"
+  this.openBracket
+  for i, a in value.ikids:
+    if i > 0: this.comma
+    this.value a
+  this.closeBracket
 
   if value.n != nil:
     this.key "n"
@@ -644,30 +458,33 @@ proc value(this: var DebugPrinter; value: PNode) =
 
 
 proc debug(n: PSym; conf: ConfigRef) =
-  var this: DebugPrinter
-  this.visited = initTable[pointer, int]()
-  this.renderSymType = true
-  this.useColor = not defined(windows)
+  var this = DebugPrinter(
+    visited: initTable[pointer, int](),
+    renderSymType: true,
+    useColor: not defined(windows)
+  )
   this.value(n)
   echo($this.res)
 
 proc debug(n: PType; conf: ConfigRef) =
-  var this: DebugPrinter
-  this.visited = initTable[pointer, int]()
-  this.renderSymType = true
-  this.useColor = not defined(windows)
+  var this = DebugPrinter(
+    visited: initTable[pointer, int](),
+    renderSymType: true,
+    useColor: not defined(windows)
+  )
   this.value(n)
   echo($this.res)
 
 proc debug(n: PNode; conf: ConfigRef) =
-  var this: DebugPrinter
-  this.visited = initTable[pointer, int]()
-  #this.renderSymType = true
-  this.useColor = not defined(windows)
+  var this = DebugPrinter(
+    visited: initTable[pointer, int](),
+    renderSymType: false,
+    useColor: not defined(windows)
+  )
   this.value(n)
   echo($this.res)
 
-proc nextTry(h, maxHash: Hash): Hash =
+proc nextTry(h, maxHash: Hash): Hash {.inline.} =
   result = ((5 * h) + 1) and maxHash
   # For any initial h in range(maxHash), repeating that maxHash times
   # generates each int in range(maxHash) exactly once (see any text on
@@ -890,125 +707,12 @@ proc initTabIter*(ti: var TTabIter, tab: TStrTable): PSym =
     result = nextIter(ti, tab)
 
 iterator items*(tab: TStrTable): PSym =
-  var it: TTabIter
+  var it: TTabIter = default(TTabIter)
   var s = initTabIter(it, tab)
   while s != nil:
     yield s
     s = nextIter(it, tab)
 
-proc hasEmptySlot(data: TIdPairSeq): bool =
-  for h in 0..high(data):
-    if data[h].key == nil:
-      return true
-  result = false
-
-proc idTableRawGet(t: TIdTable, key: int): int =
-  var h: Hash
-  h = key and high(t.data)    # start with real hash value
-  while t.data[h].key != nil:
-    if t.data[h].key.id == key:
-      return h
-    h = nextTry(h, high(t.data))
-  result = - 1
-
-proc idTableHasObjectAsKey(t: TIdTable, key: PIdObj): bool =
-  var index = idTableRawGet(t, key.id)
-  if index >= 0: result = t.data[index].key == key
-  else: result = false
-
-proc idTableGet(t: TIdTable, key: PIdObj): RootRef =
-  var index = idTableRawGet(t, key.id)
-  if index >= 0: result = t.data[index].val
-  else: result = nil
-
-proc idTableGet(t: TIdTable, key: int): RootRef =
-  var index = idTableRawGet(t, key)
-  if index >= 0: result = t.data[index].val
-  else: result = nil
-
-iterator pairs*(t: TIdTable): tuple[key: int, value: RootRef] =
-  for i in 0..high(t.data):
-    if t.data[i].key != nil:
-      yield (t.data[i].key.id, t.data[i].val)
-
-proc idTableRawInsert(data: var TIdPairSeq, key: PIdObj, val: RootRef) =
-  var h: Hash
-  h = key.id and high(data)
-  while data[h].key != nil:
-    assert(data[h].key.id != key.id)
-    h = nextTry(h, high(data))
-  assert(data[h].key == nil)
-  data[h].key = key
-  data[h].val = val
-
-proc idTablePut(t: var TIdTable, key: PIdObj, val: RootRef) =
-  var
-    index: int
-    n: TIdPairSeq
-  index = idTableRawGet(t, key.id)
-  if index >= 0:
-    assert(t.data[index].key != nil)
-    t.data[index].val = val
-  else:
-    if mustRehash(t.data.len, t.counter):
-      newSeq(n, t.data.len * GrowthFactor)
-      for i in 0..high(t.data):
-        if t.data[i].key != nil:
-          idTableRawInsert(n, t.data[i].key, t.data[i].val)
-      assert(hasEmptySlot(n))
-      swap(t.data, n)
-    idTableRawInsert(t.data, key, val)
-    inc(t.counter)
-
-iterator idTablePairs*(t: TIdTable): tuple[key: PIdObj, val: RootRef] =
-  for i in 0..high(t.data):
-    if not isNil(t.data[i].key): yield (t.data[i].key, t.data[i].val)
-
-proc idNodeTableRawGet(t: TIdNodeTable, key: PIdObj): int =
-  var h: Hash
-  h = key.id and high(t.data) # start with real hash value
-  while t.data[h].key != nil:
-    if t.data[h].key.id == key.id:
-      return h
-    h = nextTry(h, high(t.data))
-  result = - 1
-
-proc idNodeTableGet(t: TIdNodeTable, key: PIdObj): PNode =
-  var index: int
-  index = idNodeTableRawGet(t, key)
-  if index >= 0: result = t.data[index].val
-  else: result = nil
-
-proc idNodeTableRawInsert(data: var TIdNodePairSeq, key: PIdObj, val: PNode) =
-  var h: Hash
-  h = key.id and high(data)
-  while data[h].key != nil:
-    assert(data[h].key.id != key.id)
-    h = nextTry(h, high(data))
-  assert(data[h].key == nil)
-  data[h].key = key
-  data[h].val = val
-
-proc idNodeTablePut(t: var TIdNodeTable, key: PIdObj, val: PNode) =
-  var index = idNodeTableRawGet(t, key)
-  if index >= 0:
-    assert(t.data[index].key != nil)
-    t.data[index].val = val
-  else:
-    if mustRehash(t.data.len, t.counter):
-      var n: TIdNodePairSeq
-      newSeq(n, t.data.len * GrowthFactor)
-      for i in 0..high(t.data):
-        if t.data[i].key != nil:
-          idNodeTableRawInsert(n, t.data[i].key, t.data[i].val)
-      swap(t.data, n)
-    idNodeTableRawInsert(t.data, key, val)
-    inc(t.counter)
-
-iterator pairs*(t: TIdNodeTable): tuple[key: PIdObj, val: PNode] =
-  for i in 0..high(t.data):
-    if not isNil(t.data[i].key): yield (t.data[i].key, t.data[i].val)
-
 proc initIITable(x: var TIITable) =
   x.counter = 0
   newSeq(x.data, StartSize)
@@ -1054,15 +758,8 @@ proc iiTablePut(t: var TIITable, key, val: int) =
     iiTableRawInsert(t.data, key, val)
     inc(t.counter)
 
-proc isAddrNode*(n: PNode): bool =
-  case n.kind
-    of nkAddr, nkHiddenAddr: true
-    of nkCallKinds:
-      if n[0].kind == nkSym and n[0].sym.magic == mAddr: true
-      else: false
-    else: false
-
 proc listSymbolNames*(symbols: openArray[PSym]): string =
+  result = ""
   for sym in symbols:
     if result.len > 0:
       result.add ", "

compiler/astmsgs.nim

@@ -5,7 +5,7 @@ import options, ast, msgs
 proc typSym*(t: PType): PSym =
   result = t.sym
   if result == nil and t.kind == tyGenericInst: # this might need to be refined
-    result = t[0].sym
+    result = t.genericHead.sym
 
 proc addDeclaredLoc*(result: var string, conf: ConfigRef; sym: PSym) =
   result.add " [$1 declared in $2]" % [sym.kind.toHumanStr, toFileLineCol(conf, sym.info)]

compiler/astyaml.nim

@@ -0,0 +1,154 @@
+#
+#
+#           The Nim Compiler
+#        (c) Copyright 2012 Andreas Rumpf
+#
+#    See the file "copying.txt", included in this
+#    distribution, for details about the copyright.
+#
+
+# AST YAML printing
+
+import "."/[ast, lineinfos, msgs, options, rodutils]
+import std/[intsets, strutils]
+
+proc addYamlString*(res: var string; s: string) =
+  res.add "\""
+  for c in s:
+    case c
+    of '\0' .. '\x1F', '\x7F' .. '\xFF':
+      res.add("\\u" & strutils.toHex(ord(c), 4))
+    of '\"', '\\':
+      res.add '\\' & c
+    else:
+      res.add c
+
+  res.add('\"')
+
+proc makeYamlString(s: string): string =
+  result = ""
+  result.addYamlString(s)
+
+proc flagsToStr[T](flags: set[T]): string =
+  if flags == {}:
+    result = "[]"
+  else:
+    result = ""
+    for x in items(flags):
+      if result != "":
+        result.add(", ")
+      result.addYamlString($x)
+    result = "[" & result & "]"
+
+proc lineInfoToStr*(conf: ConfigRef; info: TLineInfo): string =
+  result = "["
+  result.addYamlString(toFilename(conf, info))
+  result.addf ", $1, $2]", [toLinenumber(info), toColumn(info)]
+
+proc treeToYamlAux(res: var string; conf: ConfigRef; n: PNode; marker: var IntSet; indent, maxRecDepth: int)
+proc symToYamlAux(res: var string; conf: ConfigRef; n: PSym; marker: var IntSet; indent, maxRecDepth: int)
+proc typeToYamlAux(res: var string; conf: ConfigRef; n: PType; marker: var IntSet; indent, maxRecDepth: int)
+
+proc symToYamlAux(res: var string; conf: ConfigRef; n: PSym; marker: var IntSet; indent: int; maxRecDepth: int) =
+  if n == nil:
+    res.add("null")
+  elif containsOrIncl(marker, n.id):
+    res.addYamlString(n.name.s)
+  else:
+    let istr = spaces(indent * 4)
+
+    res.addf("kind: $1", [makeYamlString($n.kind)])
+    res.addf("\n$1name: $2", [istr, makeYamlString(n.name.s)])
+    res.addf("\n$1typ: ", [istr])
+    res.typeToYamlAux(conf, n.typ, marker, indent + 1, maxRecDepth - 1)
+    if conf != nil:
+      # if we don't pass the config, we probably don't care about the line info
+      res.addf("\n$1info: $2", [istr, lineInfoToStr(conf, n.info)])
+    if card(n.flags) > 0:
+      res.addf("\n$1flags: $2", [istr, flagsToStr(n.flags)])
+    res.addf("\n$1magic: $2", [istr, makeYamlString($n.magic)])
+    res.addf("\n$1ast: ", [istr])
+    res.treeToYamlAux(conf, n.ast, marker, indent + 1, maxRecDepth - 1)
+    res.addf("\n$1options: $2", [istr, flagsToStr(n.options)])
+    res.addf("\n$1position: $2", [istr, $n.position])
+    res.addf("\n$1k: $2", [istr, makeYamlString($n.loc.k)])
+    res.addf("\n$1storage: $2", [istr, makeYamlString($n.loc.storage)])
+    if card(n.loc.flags) > 0:
+      res.addf("\n$1flags: $2", [istr, makeYamlString($n.loc.flags)])
+    res.addf("\n$1snippet: $2", [istr, n.loc.snippet])
+    res.addf("\n$1lode: $2", [istr])
+    res.treeToYamlAux(conf, n.loc.lode, marker, indent + 1, maxRecDepth - 1)
+
+proc typeToYamlAux(res: var string; conf: ConfigRef; n: PType; marker: var IntSet; indent: int; maxRecDepth: int) =
+  if n == nil:
+    res.add("null")
+  elif containsOrIncl(marker, n.id):
+    res.addf "\"$1 @$2\"" % [$n.kind, strutils.toHex(cast[uint](n), sizeof(n) * 2)]
+  else:
+    let istr = spaces(indent * 4)
+    res.addf("kind: $2", [istr, makeYamlString($n.kind)])
+    res.addf("\n$1sym: ")
+    res.symToYamlAux(conf, n.sym, marker, indent + 1, maxRecDepth - 1)
+    res.addf("\n$1n: ")
+    res.treeToYamlAux(conf, n.n, marker, indent + 1, maxRecDepth - 1)
+    if card(n.flags) > 0:
+      res.addf("\n$1flags: $2", [istr, flagsToStr(n.flags)])
+    res.addf("\n$1callconv: $2", [istr, makeYamlString($n.callConv)])
+    res.addf("\n$1size: $2", [istr, $(n.size)])
+    res.addf("\n$1align: $2", [istr, $(n.align)])
+    if n.hasElementType:
+      res.addf("\n$1sons:")
+      for a in n.kids:
+        res.addf("\n  - ")
+        res.typeToYamlAux(conf, a, marker, indent + 1, maxRecDepth - 1)
+
+proc treeToYamlAux(res: var string; conf: ConfigRef; n: PNode; marker: var IntSet; indent: int;
+                   maxRecDepth: int) =
+  if n == nil:
+    res.add("null")
+  else:
+    var istr = spaces(indent * 4)
+    res.addf("kind: $1" % [makeYamlString($n.kind)])
+
+    if maxRecDepth != 0:
+      if conf != nil:
+        res.addf("\n$1info: $2", [istr, lineInfoToStr(conf, n.info)])
+      case n.kind
+      of nkCharLit .. nkInt64Lit:
+        res.addf("\n$1intVal: $2", [istr, $(n.intVal)])
+      of nkFloatLit, nkFloat32Lit, nkFloat64Lit:
+        res.addf("\n$1floatVal: $2", [istr, n.floatVal.toStrMaxPrecision])
+      of nkStrLit .. nkTripleStrLit:
+        res.addf("\n$1strVal: $2", [istr, makeYamlString(n.strVal)])
+      of nkSym:
+        res.addf("\n$1sym: ", [istr])
+        res.symToYamlAux(conf, n.sym, marker, indent + 1, maxRecDepth)
+      of nkIdent:
+        if n.ident != nil:
+          res.addf("\n$1ident: $2", [istr, makeYamlString(n.ident.s)])
+        else:
+          res.addf("\n$1ident: null", [istr])
+      else:
+        if n.len > 0:
+          res.addf("\n$1sons: ", [istr])
+          for i in 0 ..< n.len:
+            res.addf("\n$1  - ", [istr])
+            res.treeToYamlAux(conf, n[i], marker, indent + 1, maxRecDepth - 1)
+      if n.typ != nil:
+        res.addf("\n$1typ: ", [istr])
+        res.typeToYamlAux(conf, n.typ, marker, indent + 1, maxRecDepth)
+
+proc treeToYaml*(conf: ConfigRef; n: PNode; indent: int = 0; maxRecDepth: int = -1): string =
+  var marker = initIntSet()
+  result = newStringOfCap(1024)
+  result.treeToYamlAux(conf, n, marker, indent, maxRecDepth)
+
+proc typeToYaml*(conf: ConfigRef; n: PType; indent: int = 0; maxRecDepth: int = -1): string =
+  var marker = initIntSet()
+  result = newStringOfCap(1024)
+  result.typeToYamlAux(conf, n, marker, indent, maxRecDepth)
+
+proc symToYaml*(conf: ConfigRef; n: PSym; indent: int = 0; maxRecDepth: int = -1): string =
+  var marker = initIntSet()
+  result = newStringOfCap(1024)
+  result.symToYamlAux(conf, n, marker, indent, maxRecDepth)

compiler/backendpragmas.nim

@@ -1,25 +0,0 @@
-import pragmas, options, ast, trees
-
-proc pushBackendOption(optionsStack: var seq[TOptions], options: var TOptions) =
-  optionsStack.add options
-
-proc popBackendOption(optionsStack: var seq[TOptions], options: var TOptions) =
-  options = optionsStack[^1]
-  optionsStack.setLen(optionsStack.len-1)
-
-proc processPushBackendOption*(optionsStack: var seq[TOptions], options: var TOptions,
-                           n: PNode, start: int) =
-  pushBackendOption(optionsStack, options)
-  for i in start..<n.len:
-    let it = n[i]
-    if it.kind in nkPragmaCallKinds and it.len == 2 and it[1].kind == nkIntLit:
-      let sw = whichPragma(it[0])
-      let opts = pragmaToOptions(sw)
-      if opts != {}:
-        if it[1].intVal != 0:
-          options.incl opts
-        else:
-          options.excl opts
-
-template processPopBackendOption*(optionsStack: var seq[TOptions], options: var TOptions) =
-  popBackendOption(optionsStack, options)

compiler/bitsets.nim

@@ -87,5 +87,11 @@ const populationCount: array[uint8, uint8] = block:
     arr
 
 proc bitSetCard*(x: TBitSet): BiggestInt =
+  result = 0
   for it in x:
     result.inc int(populationCount[it])
+
+proc bitSetToWord*(s: TBitSet; size: int): BiggestUInt =
+  result = 0
+  for j in 0..<size:
+    if j < s.len: result = result or (BiggestUInt(s[j]) shl (j * 8))

compiler/btrees.nim

@@ -38,6 +38,7 @@ template less(a, b): bool = cmp(a, b) < 0
 template eq(a, b): bool = cmp(a, b) == 0
 
 proc getOrDefault*[Key, Val](b: BTree[Key, Val], key: Key): Val =
+  result = default(Val)
   var x = b.root
   while x.isInternal:
     for j in 0..<x.entries:

compiler/cbuilderbase.nim

@@ -0,0 +1,6 @@
+type
+  Snippet = string
+  Builder = string
+
+template newBuilder(s: string): Builder =
+  s

compiler/cbuilderdecls.nim

@@ -0,0 +1,349 @@
+type VarKind = enum
+  Local
+  Global
+  Threadvar
+  Const
+  AlwaysConst ## const even on C++
+
+proc addVarHeader(builder: var Builder, kind: VarKind) =
+  ## adds modifiers for given var kind:
+  ## Local has no modifier
+  ## Global has `static` modifier
+  ## Const has `static NIM_CONST` modifier
+  ## AlwaysConst has `static const` modifier (NIM_CONST is no-op on C++)
+  ## Threadvar is unimplemented
+  case kind
+  of Local: discard
+  of Global:
+    builder.add("static ")
+  of Const:
+    builder.add("static NIM_CONST ")
+  of AlwaysConst:
+    builder.add("static const ")
+  of Threadvar:
+    doAssert false, "unimplemented"
+
+proc addVar(builder: var Builder, kind: VarKind = Local, name: string, typ: Snippet, initializer: Snippet = "") =
+  ## adds a variable declaration to the builder
+  builder.addVarHeader(kind)
+  builder.add(typ)
+  builder.add(" ")
+  builder.add(name)
+  if initializer.len != 0:
+    builder.add(" = ")
+    builder.add(initializer)
+  builder.add(";\n")
+
+template addVarWithType(builder: var Builder, kind: VarKind = Local, name: string, body: typed) =
+  ## adds a variable declaration to the builder, with the `body` building the type
+  builder.addVarHeader(kind)
+  body
+  builder.add(" ")
+  builder.add(name)
+  builder.add(";\n")
+
+template addVarWithTypeAndInitializer(builder: var Builder, kind: VarKind = Local, name: string,
+                                      typeBody, initializerBody: typed) =
+  ## adds a variable declaration to the builder, with `typeBody` building the type, and
+  ## `initializerBody` building the initializer. initializer must be provided
+  builder.addVarHeader(kind)
+  typeBody
+  builder.add(" ")
+  builder.add(name)
+  builder.add(" = ")
+  initializerBody
+  builder.add(";\n")
+
+proc addArrayVar(builder: var Builder, kind: VarKind = Local, name: string, elementType: Snippet, len: int, initializer: Snippet = "") =
+  ## adds an array variable declaration to the builder
+  builder.addVarHeader(kind)
+  builder.add(elementType)
+  builder.add(" ")
+  builder.add(name)
+  builder.add("[")
+  builder.addInt(len)
+  builder.add("]")
+  if initializer.len != 0:
+    builder.add(" = ")
+    builder.add(initializer)
+  builder.add(";\n")
+
+template addArrayVarWithInitializer(builder: var Builder, kind: VarKind = Local, name: string, elementType: Snippet, len: int, body: typed) =
+  ## adds an array variable declaration to the builder with the initializer built according to `body`
+  builder.addVarHeader(kind)
+  builder.add(elementType)
+  builder.add(" ")
+  builder.add(name)
+  builder.add("[")
+  builder.addInt(len)
+  builder.add("] = ")
+  body
+  builder.add(";\n")
+
+template addTypedef(builder: var Builder, name: string, typeBody: typed) =
+  ## adds a typedef declaration to the builder with name `name` and type as
+  ## built in `typeBody`
+  builder.add("typedef ")
+  typeBody
+  builder.add(" ")
+  builder.add(name)
+  builder.add(";\n")
+
+template addArrayTypedef(builder: var Builder, name: string, len: int, typeBody: typed) =
+  ## adds an array typedef declaration to the builder with name `name`,
+  ## length `len`, and element type as built in `typeBody`
+  builder.add("typedef ")
+  typeBody
+  builder.add(" ")
+  builder.add(name)
+  builder.add("[")
+  builder.addInt(len)
+  builder.add("];\n")
+
+type
+  StructInitializerKind = enum
+    siOrderedStruct ## struct constructor, but without named fields on C
+    siNamedStruct ## struct constructor, with named fields i.e. C99 designated initializer
+    siArray ## array constructor
+    siWrapper ## wrapper for a single field, generates it verbatim
+
+  StructInitializer = object
+    ## context for building struct initializers, i.e. `{ field1, field2 }`
+    kind: StructInitializerKind
+      ## if true, fields will not be named, instead values are placed in order
+    needsComma: bool
+
+proc initStructInitializer(builder: var Builder, kind: StructInitializerKind): StructInitializer =
+  ## starts building a struct initializer, i.e. braced initializer list
+  result = StructInitializer(kind: kind, needsComma: false)
+  if kind != siWrapper:
+    builder.add("{")
+
+template addField(builder: var Builder, constr: var StructInitializer, name: string, valueBody: typed) =
+  ## adds a field to a struct initializer, with the value built in `valueBody`
+  if constr.needsComma:
+    assert constr.kind != siWrapper, "wrapper constructor cannot have multiple fields"
+    builder.add(", ")
+  else:
+    constr.needsComma = true
+  case constr.kind
+  of siArray, siWrapper:
+    # no name, can just add value
+    valueBody
+  of siOrderedStruct:
+    # no name, can just add value on C
+    assert name.len != 0, "name has to be given for struct initializer field"
+    valueBody
+  of siNamedStruct:
+    assert name.len != 0, "name has to be given for struct initializer field"
+    builder.add(".")
+    builder.add(name)
+    builder.add(" = ")
+    valueBody
+
+proc finishStructInitializer(builder: var Builder, constr: StructInitializer) =
+  ## finishes building a struct initializer
+  if constr.kind != siWrapper:
+    builder.add("}")
+
+template addStructInitializer(builder: var Builder, constr: out StructInitializer, kind: StructInitializerKind, body: typed) =
+  ## builds a struct initializer, i.e. `{ field1, field2 }`
+  ## a `var StructInitializer` must be declared and passed as a parameter so
+  ## that it can be used with `addField`
+  constr = builder.initStructInitializer(kind)
+  body
+  builder.finishStructInitializer(constr)
+
+proc addField(obj: var Builder; name, typ: Snippet; isFlexArray: bool = false; initializer: Snippet = "") =
+  ## adds a field inside a struct/union type
+  obj.add('\t')
+  obj.add(typ)
+  obj.add(" ")
+  obj.add(name)
+  if isFlexArray:
+    obj.add("[SEQ_DECL_SIZE]")
+  if initializer.len != 0:
+    obj.add(initializer)
+  obj.add(";\n")
+
+proc addArrayField(obj: var Builder; name, elementType: Snippet; len: int; initializer: Snippet = "") =
+  ## adds an array field inside a struct/union type
+  obj.add('\t')
+  obj.add(elementType)
+  obj.add(" ")
+  obj.add(name)
+  obj.add("[")
+  obj.addInt(len)
+  obj.add("]")
+  if initializer.len != 0:
+    obj.add(initializer)
+  obj.add(";\n")
+
+proc addField(obj: var Builder; field: PSym; name, typ: Snippet; isFlexArray: bool = false; initializer: Snippet = "") =
+  ## adds an field inside a struct/union type, based on an `skField` symbol
+  obj.add('\t')
+  if field.alignment > 0:
+    obj.add("NIM_ALIGN(")
+    obj.addInt(field.alignment)
+    obj.add(") ")
+  obj.add(typ)
+  if sfNoalias in field.flags:
+    obj.add(" NIM_NOALIAS")
+  obj.add(" ")
+  obj.add(name)
+  if isFlexArray:
+    obj.add("[SEQ_DECL_SIZE]")
+  if field.bitsize != 0:
+    obj.add(":")
+    obj.addInt(field.bitsize)
+  if initializer.len != 0:
+    obj.add(initializer)
+  obj.add(";\n")
+
+type
+  BaseClassKind = enum
+    ## denotes how and whether or not the base class/RTTI should be stored
+    bcNone, bcCppInherit, bcSupField, bcNoneRtti, bcNoneTinyRtti
+  StructBuilderInfo = object
+    ## context for building `struct` types
+    baseKind: BaseClassKind
+    named: bool
+    preFieldsLen: int
+
+proc structOrUnion(t: PType): Snippet =
+  let t = t.skipTypes({tyAlias, tySink})
+  if tfUnion in t.flags: "union"
+  else: "struct"
+
+proc startSimpleStruct(obj: var Builder; m: BModule; name: string; baseType: Snippet): StructBuilderInfo =
+  result = StructBuilderInfo(baseKind: bcNone, named: name.len != 0)
+  obj.add("struct")
+  if result.named:
+    obj.add(" ")
+    obj.add(name)
+  if baseType.len != 0:
+    if m.compileToCpp:
+      result.baseKind = bcCppInherit
+    else:
+      result.baseKind = bcSupField
+  if result.baseKind == bcCppInherit:
+    obj.add(" : public ")
+    obj.add(baseType)
+  obj.add(" ")
+  obj.add("{\n")
+  result.preFieldsLen = obj.len
+  if result.baseKind == bcSupField:
+    obj.addField(name = "Sup", typ = baseType)
+
+proc finishSimpleStruct(obj: var Builder; m: BModule; info: StructBuilderInfo) =
+  if info.baseKind == bcNone and info.preFieldsLen == obj.len:
+    # no fields were added, add dummy field
+    obj.addField(name = "dummy", typ = "char")
+  if info.named:
+    obj.add("};\n")
+  else:
+    obj.add("}")
+
+template addSimpleStruct(obj: var Builder; m: BModule; name: string; baseType: Snippet; body: typed) =
+  ## builds a struct type not based on a Nim type with fields according to `body`,
+  ## `name` can be empty to build as a type expression and not a statement
+  let info = startSimpleStruct(obj, m, name, baseType)
+  body
+  finishSimpleStruct(obj, m, info)
+
+proc startStruct(obj: var Builder; m: BModule; t: PType; name: string; baseType: Snippet): StructBuilderInfo =
+  result = StructBuilderInfo(baseKind: bcNone, named: name.len != 0)
+  if tfPacked in t.flags:
+    if hasAttribute in CC[m.config.cCompiler].props:
+      obj.add(structOrUnion(t))
+      obj.add(" __attribute__((__packed__))")
+    else:
+      obj.add("#pragma pack(push, 1)\n")
+      obj.add(structOrUnion(t))
+  else:
+    obj.add(structOrUnion(t))
+  if result.named:
+    obj.add(" ")
+    obj.add(name)
+  if t.kind == tyObject:
+    if t.baseClass == nil:
+      if lacksMTypeField(t):
+        result.baseKind = bcNone
+      elif optTinyRtti in m.config.globalOptions:
+        result.baseKind = bcNoneTinyRtti
+      else:
+        result.baseKind = bcNoneRtti
+    elif m.compileToCpp:
+      result.baseKind = bcCppInherit
+    else:
+      result.baseKind = bcSupField
+  elif baseType.len != 0:
+    if m.compileToCpp:
+      result.baseKind = bcCppInherit
+    else:
+      result.baseKind = bcSupField
+  if result.baseKind == bcCppInherit:
+    obj.add(" : public ")
+    obj.add(baseType)
+  obj.add(" ")
+  obj.add("{\n")
+  result.preFieldsLen = obj.len
+  case result.baseKind
+  of bcNone:
+    # rest of the options add a field or don't need it due to inheritance,
+    # we need to add the dummy field for uncheckedarray ahead of time
+    # so that it remains trailing
+    if t.itemId notin m.g.graph.memberProcsPerType and
+        t.n != nil and t.n.len == 1 and t.n[0].kind == nkSym and
+        t.n[0].sym.typ.skipTypes(abstractInst).kind == tyUncheckedArray:
+      # only consists of flexible array field, add *initial* dummy field
+      obj.addField(name = "dummy", typ = "char")
+  of bcCppInherit: discard
+  of bcNoneRtti:
+    obj.addField(name = "m_type", typ = ptrType(cgsymValue(m, "TNimType")))
+  of bcNoneTinyRtti:
+    obj.addField(name = "m_type", typ = ptrType(cgsymValue(m, "TNimTypeV2")))
+  of bcSupField:
+    obj.addField(name = "Sup", typ = baseType)
+
+proc finishStruct(obj: var Builder; m: BModule; t: PType; info: StructBuilderInfo) =
+  if info.baseKind == bcNone and info.preFieldsLen == obj.len and
+      t.itemId notin m.g.graph.memberProcsPerType:
+    # no fields were added, add dummy field
+    obj.addField(name = "dummy", typ = "char")
+  if info.named:
+    obj.add("};\n")
+  else:
+    obj.add("}")
+  if tfPacked in t.flags and hasAttribute notin CC[m.config.cCompiler].props:
+    obj.add("#pragma pack(pop)\n")
+
+template addStruct(obj: var Builder; m: BModule; typ: PType; name: string; baseType: Snippet; body: typed) =
+  ## builds a struct type directly based on `typ` with fields according to `body`,
+  ## `name` can be empty to build as a type expression and not a statement
+  let info = startStruct(obj, m, typ, name, baseType)
+  body
+  finishStruct(obj, m, typ, info)
+
+template addFieldWithStructType(obj: var Builder; m: BModule; parentTyp: PType; fieldName: string, body: typed) =
+  ## adds a field with a `struct { ... }` type, building the fields according to `body`
+  obj.add('\t')
+  if tfPacked in parentTyp.flags:
+    if hasAttribute in CC[m.config.cCompiler].props:
+      obj.add("struct __attribute__((__packed__)) {\n")
+    else:
+      obj.add("#pragma pack(push, 1)\nstruct {")
+  else:
+    obj.add("struct {\n")
+  body
+  obj.add("} ")
+  obj.add(fieldName)
+  obj.add(";\n")
+  if tfPacked in parentTyp.flags and hasAttribute notin CC[m.config.cCompiler].props:
+    result.add("#pragma pack(pop)\n")
+
+template addAnonUnion(obj: var Builder; body: typed) =
+  ## adds an anonymous union i.e. `union { ... };` with fields according to `body`
+  obj.add "union{\n"
+  body
+  obj.add("};\n")

compiler/cbuilderexprs.nim

@@ -0,0 +1,26 @@
+# XXX make complex ones like bitOr use builder instead
+# XXX add stuff like NI, NIM_NIL as constants
+
+proc ptrType(t: Snippet): Snippet =
+  t & "*"
+
+const
+  CallingConvToStr: array[TCallingConvention, string] = ["N_NIMCALL",
+    "N_STDCALL", "N_CDECL", "N_SAFECALL",
+    "N_SYSCALL", # this is probably not correct for all platforms,
+                 # but one can #define it to what one wants
+    "N_INLINE", "N_NOINLINE", "N_FASTCALL", "N_THISCALL", "N_CLOSURE", "N_NOCONV",
+    "N_NOCONV" #ccMember is N_NOCONV
+    ]
+
+proc procPtrType(conv: TCallingConvention, rettype: Snippet, name: string): Snippet =
+  CallingConvToStr[conv] & "_PTR(" & rettype & ", " & name & ")"
+
+proc cCast(typ, value: Snippet): Snippet =
+  "((" & typ & ") " & value & ")"
+
+proc cAddr(value: Snippet): Snippet =
+  "&" & value
+
+proc bitOr(a, b: Snippet): Snippet =
+  "(" & a & " | " & b & ")"

compiler/ccgcalls.nim

@@ -47,6 +47,7 @@ proc preventNrvo(p: BProc; dest, le, ri: PNode): bool =
         # cannot analyse the location; assume the worst
         return true
 
+  result = false
   if le != nil:
     for i in 1..<ri.len:
       let r = ri[i]
@@ -75,6 +76,23 @@ proc isHarmlessStore(p: BProc; canRaise: bool; d: TLoc): bool =
   else:
     result = false
 
+proc cleanupTemp(p: BProc; returnType: PType, tmp: TLoc): bool =
+  if returnType.kind in {tyVar, tyLent}:
+    # we don't need to worry about var/lent return types
+    result = false
+  elif hasDestructor(returnType) and getAttachedOp(p.module.g.graph, returnType, attachedDestructor) != nil:
+    let dtor = getAttachedOp(p.module.g.graph, returnType, attachedDestructor)
+    var op = initLocExpr(p, newSymNode(dtor))
+    var callee = rdLoc(op)
+    let destroy = if dtor.typ.firstParamType.kind == tyVar:
+        callee & "(&" & rdLoc(tmp) & ")"
+      else:
+        callee & "(" & rdLoc(tmp) & ")"
+    raiseExitCleanup(p, destroy)
+    result = true
+  else:
+    result = false
+
 proc fixupCall(p: BProc, le, ri: PNode, d: var TLoc,
                callee, params: Rope) =
   let canRaise = p.config.exc == excGoto and canRaiseDisp(p, ri[0])
@@ -82,9 +100,9 @@ proc fixupCall(p: BProc, le, ri: PNode, d: var TLoc,
   var pl = callee & "(" & params
   # getUniqueType() is too expensive here:
   var typ = skipTypes(ri[0].typ, abstractInst)
-  if typ[0] != nil:
+  if typ.returnType != nil:
     var flags: TAssignmentFlags = {}
-    if typ[0].kind in {tyOpenArray, tyVarargs}:
+    if typ.returnType.kind in {tyOpenArray, tyVarargs}:
       # perhaps generate no temp if the call doesn't have side effects
       flags.incl needTempForOpenArray
     if isInvalidReturnType(p.config, typ):
@@ -92,7 +110,7 @@ proc fixupCall(p: BProc, le, ri: PNode, d: var TLoc,
       # beware of 'result = p(result)'. We may need to allocate a temporary:
       if d.k in {locTemp, locNone} or not preventNrvo(p, d.lode, le, ri):
         # Great, we can use 'd':
-        if d.k == locNone: getTemp(p, typ[0], d, needsInit=true)
+        if d.k == locNone: d = getTemp(p, typ.returnType, needsInit=true)
         elif d.k notin {locTemp} and not hasNoInit(ri):
           # reset before pass as 'result' var:
           discard "resetLoc(p, d)"
@@ -100,8 +118,7 @@ proc fixupCall(p: BProc, le, ri: PNode, d: var TLoc,
         pl.add(");\n")
         line(p, cpsStmts, pl)
       else:
-        var tmp: TLoc
-        getTemp(p, typ[0], tmp, needsInit=true)
+        var tmp: TLoc = getTemp(p, typ.returnType, needsInit=true)
         pl.add(addrLoc(p.config, tmp))
         pl.add(");\n")
         line(p, cpsStmts, pl)
@@ -115,66 +132,74 @@ proc fixupCall(p: BProc, le, ri: PNode, d: var TLoc,
           # with them to prevent undefined behaviour and because the codegen
           # is free to emit expressions multiple times!
           d.k = locCall
-          d.r = pl
+          d.snippet = pl
           excl d.flags, lfSingleUse
         else:
           if d.k == locNone and p.splitDecls == 0:
-            getTempCpp(p, typ[0], d, pl)
+            d = getTempCpp(p, typ.returnType, pl)
           else:
-            if d.k == locNone: getTemp(p, typ[0], d)
-            var list: TLoc
-            initLoc(list, locCall, d.lode, OnUnknown)
-            list.r = pl
-            genAssignment(p, d, list, {}) # no need for deep copying
+            if d.k == locNone: d = getTemp(p, typ.returnType)
+            var list = initLoc(locCall, d.lode, OnUnknown)
+            list.snippet = pl
+            genAssignment(p, d, list, {needAssignCall}) # no need for deep copying
             if canRaise: raiseExit(p)
 
       elif isHarmlessStore(p, canRaise, d):
-        if d.k == locNone: getTemp(p, typ[0], d)
+        var useTemp = false
+        if d.k == locNone:
+          useTemp = true
+          d = getTemp(p, typ.returnType)
         assert(d.t != nil)        # generate an assignment to d:
-        var list: TLoc
-        initLoc(list, locCall, d.lode, OnUnknown)
-        list.r = pl
-        genAssignment(p, d, list, flags) # no need for deep copying
-        if canRaise: raiseExit(p)
+        var list = initLoc(locCall, d.lode, OnUnknown)
+        list.snippet = pl
+        genAssignment(p, d, list, flags+{needAssignCall}) # no need for deep copying
+        if canRaise:
+          if not (useTemp and cleanupTemp(p, typ.returnType, d)):
+            raiseExit(p)
       else:
-        var tmp: TLoc
-        getTemp(p, typ[0], tmp, needsInit=true)
-        var list: TLoc
-        initLoc(list, locCall, d.lode, OnUnknown)
-        list.r = pl
-        genAssignment(p, tmp, list, flags) # no need for deep copying
-        if canRaise: raiseExit(p)
+        var tmp: TLoc = getTemp(p, typ.returnType, needsInit=true)
+        var list = initLoc(locCall, d.lode, OnUnknown)
+        list.snippet = pl
+        genAssignment(p, tmp, list, flags+{needAssignCall}) # no need for deep copying
+        if canRaise:
+          if not cleanupTemp(p, typ.returnType, tmp):
+            raiseExit(p)
         genAssignment(p, d, tmp, {})
   else:
     pl.add(");\n")
     line(p, cpsStmts, pl)
     if canRaise: raiseExit(p)
 
-proc genBoundsCheck(p: BProc; arr, a, b: TLoc)
+proc genBoundsCheck(p: BProc; arr, a, b: TLoc; arrTyp: PType)
 
 proc reifiedOpenArray(n: PNode): bool {.inline.} =
   var x = n
-  while x.kind in {nkAddr, nkHiddenAddr, nkHiddenStdConv, nkHiddenDeref}:
-    x = x[0]
+  while true:
+    case x.kind
+    of {nkAddr, nkHiddenAddr, nkHiddenDeref}:
+      x = x[0]
+    of nkHiddenStdConv:
+      x = x[1]
+    else:
+      break
   if x.kind == nkSym and x.sym.kind == skParam:
     result = false
   else:
     result = true
 
 proc genOpenArraySlice(p: BProc; q: PNode; formalType, destType: PType; prepareForMutation = false): (Rope, Rope) =
-  var a, b, c: TLoc
-  initLocExpr(p, q[1], a)
-  initLocExpr(p, q[2], b)
-  initLocExpr(p, q[3], c)
-  # but first produce the required index checks:
-  if optBoundsCheck in p.options:
-    genBoundsCheck(p, a, b, c)
-  if prepareForMutation:
-    linefmt(p, cpsStmts, "#nimPrepareStrMutationV2($1);$n", [byRefLoc(p, a)])
+  var a = initLocExpr(p, q[1])
+  var b = initLocExpr(p, q[2])
+  var c = initLocExpr(p, q[3])
   # bug #23321: In the function mapType, ptrs (tyPtr, tyVar, tyLent, tyRef)
   # are mapped into ctPtrToArray, the dereference of which is skipped
-  # in the `genref`. We need to skip these ptrs here
+  # in the `genDeref`. We need to skip these ptrs here
   let ty = skipTypes(a.t, abstractVar+{tyPtr, tyRef})
+  # but first produce the required index checks:
+  if optBoundsCheck in p.options:
+    genBoundsCheck(p, a, b, c, ty)
+  if prepareForMutation:
+    linefmt(p, cpsStmts, "#nimPrepareStrMutationV2($1);$n", [byRefLoc(p, a)])
   let dest = getTypeDesc(p.module, destType)
   let lengthExpr = "($1)-($2)+1" % [rdLoc(c), rdLoc(b)]
   case ty.kind
@@ -213,6 +238,7 @@ proc genOpenArraySlice(p: BProc; q: PNode; formalType, destType: PType; prepareF
                   [rdLoc(a), rdLoc(b), dataField(p), dest, dataFieldAccessor(p, rdLoc(a))],
                 lengthExpr)
   else:
+    result = ("", "")
     internalError(p.config, "openArrayLoc: " & typeToString(a.t))
 
 proc openArrayLoc(p: BProc, formalType: PType, n: PNode; result: var Rope) =
@@ -229,11 +255,10 @@ proc openArrayLoc(p: BProc, formalType: PType, n: PNode; result: var Rope) =
         for i in 0..<q.len-1:
           genStmts(p, q[i])
         q = q.lastSon
-    let (x, y) = genOpenArraySlice(p, q, formalType, n.typ[0])
+    let (x, y) = genOpenArraySlice(p, q, formalType, n.typ.elementType)
     result.add x & ", " & y
   else:
-    var a: TLoc
-    initLocExpr(p, if n.kind == nkHiddenStdConv: n[1] else: n, a)
+    var a = initLocExpr(p, if n.kind == nkHiddenStdConv: n[1] else: n)
     case skipTypes(a.t, abstractVar+{tyStatic}).kind
     of tyOpenArray, tyVarargs:
       if reifiedOpenArray(n):
@@ -249,8 +274,7 @@ proc openArrayLoc(p: BProc, formalType: PType, n: PNode; result: var Rope) =
           optSeqDestructors in p.config.globalOptions:
         linefmt(p, cpsStmts, "#nimPrepareStrMutationV2($1);$n", [byRefLoc(p, a)])
       if ntyp.kind in {tyVar} and not compileToCpp(p.module):
-        var t: TLoc
-        t.r = "(*$1)" % [a.rdLoc]
+        var t = TLoc(snippet: "(*$1)" % [a.rdLoc])
         result.add "($4) ? ((*$1)$3) : NIM_NIL, $2" %
                      [a.rdLoc, lenExpr(p, t), dataField(p),
                       dataFieldAccessor(p, "*" & a.rdLoc)]
@@ -260,15 +284,14 @@ proc openArrayLoc(p: BProc, formalType: PType, n: PNode; result: var Rope) =
     of tyArray:
       result.add "$1, $2" % [rdLoc(a), rope(lengthOrd(p.config, a.t))]
     of tyPtr, tyRef:
-      case lastSon(a.t).kind
+      case elementType(a.t).kind
       of tyString, tySequence:
-        var t: TLoc
-        t.r = "(*$1)" % [a.rdLoc]
+        var t = TLoc(snippet: "(*$1)" % [a.rdLoc])
         result.add "($4) ? ((*$1)$3) : NIM_NIL, $2" %
                      [a.rdLoc, lenExpr(p, t), dataField(p),
                       dataFieldAccessor(p, "*" & a.rdLoc)]
       of tyArray:
-        result.add "$1, $2" % [rdLoc(a), rope(lengthOrd(p.config, lastSon(a.t)))]
+        result.add "$1, $2" % [rdLoc(a), rope(lengthOrd(p.config, elementType(a.t)))]
       else:
         internalError(p.config, "openArrayLoc: " & typeToString(a.t))
     else: internalError(p.config, "openArrayLoc: " & typeToString(a.t))
@@ -279,18 +302,17 @@ proc withTmpIfNeeded(p: BProc, a: TLoc, needsTmp: bool): TLoc =
   # Also don't regress for non ARC-builds, too risky.
   if needsTmp and a.lode.typ != nil and p.config.selectedGC in {gcArc, gcAtomicArc, gcOrc} and
       getSize(p.config, a.lode.typ) < 1024:
-    getTemp(p, a.lode.typ, result, needsInit=false)
+    result = getTemp(p, a.lode.typ, needsInit=false)
     genAssignment(p, result, a, {})
   else:
     result = a
 
 proc literalsNeedsTmp(p: BProc, a: TLoc): TLoc =
-  getTemp(p, a.lode.typ, result, needsInit=false)
+  result = getTemp(p, a.lode.typ, needsInit=false)
   genAssignment(p, result, a, {})
 
 proc genArgStringToCString(p: BProc, n: PNode; result: var Rope; needsTmp: bool) {.inline.} =
-  var a: TLoc
-  initLocExpr(p, n[0], a)
+  var a = initLocExpr(p, n[0])
   appcg(p.module, result, "#nimToCStringConv($1)", [withTmpIfNeeded(p, a, needsTmp).rdLoc])
 
 proc genArg(p: BProc, n: PNode, param: PSym; call: PNode; result: var Rope; needsTmp = false) =
@@ -300,31 +322,41 @@ proc genArg(p: BProc, n: PNode, param: PSym; call: PNode; result: var Rope; need
   elif skipTypes(param.typ, abstractVar).kind in {tyOpenArray, tyVarargs}:
     var n = if n.kind != nkHiddenAddr: n else: n[0]
     openArrayLoc(p, param.typ, n, result)
-  elif ccgIntroducedPtr(p.config, param, call[0].typ[0]) and 
+  elif ccgIntroducedPtr(p.config, param, call[0].typ.returnType) and
     (optByRef notin param.options or not p.module.compileToCpp):
-    initLocExpr(p, n, a)
+    a = initLocExpr(p, n)
     if n.kind in {nkCharLit..nkNilLit}:
       addAddrLoc(p.config, literalsNeedsTmp(p, a), result)
     else:
       addAddrLoc(p.config, withTmpIfNeeded(p, a, needsTmp), result)
   elif p.module.compileToCpp and param.typ.kind in {tyVar} and
       n.kind == nkHiddenAddr:
-    initLocExprSingleUse(p, n[0], a)
+    # bug #23748: we need to introduce a temporary here. The expression type
+    # will be a reference in C++ and we cannot create a temporary reference
+    # variable. Thus, we create a temporary pointer variable instead.
+    let needsIndirect = mapType(p.config, n[0].typ, mapTypeChooser(n[0]) == skParam) != ctArray
+    if needsIndirect:
+      n.typ() = n.typ.exactReplica
+      n.typ.flags.incl tfVarIsPtr
+    a = initLocExprSingleUse(p, n)
+    a = withTmpIfNeeded(p, a, needsTmp)
+    if needsIndirect: a.flags.incl lfIndirect
     # if the proc is 'importc'ed but not 'importcpp'ed then 'var T' still
     # means '*T'. See posix.nim for lots of examples that do that in the wild.
     let callee = call[0]
     if callee.kind == nkSym and
         {sfImportc, sfInfixCall, sfCompilerProc} * callee.sym.flags == {sfImportc} and
-        {lfHeader, lfNoDecl} * callee.sym.loc.flags != {}:
+        {lfHeader, lfNoDecl} * callee.sym.loc.flags != {} and
+        needsIndirect:
       addAddrLoc(p.config, a, result)
     else:
       addRdLoc(a, result)
   else:
-    initLocExprSingleUse(p, n, a)
-    if param.typ.kind in abstractPtrs:
+    a = initLocExprSingleUse(p, n)
+    if param.typ.kind in {tyVar, tyPtr, tyRef, tySink}:
       let typ = skipTypes(param.typ, abstractPtrs)
-      if typ.sym != nil and sfImportc in typ.sym.flags:
-        a.r = "(($1) ($2))" %
+      if not sameBackendTypePickyAliases(typ, n.typ.skipTypes(abstractPtrs)):
+        a.snippet = "(($1) ($2))" %
           [getTypeDesc(p.module, param.typ), rdCharLoc(a)]
     addRdLoc(withTmpIfNeeded(p, a, needsTmp), result)
   #assert result != nil
@@ -334,12 +366,13 @@ proc genArgNoParam(p: BProc, n: PNode; result: var Rope; needsTmp = false) =
   if n.kind == nkStringToCString:
     genArgStringToCString(p, n, result, needsTmp)
   else:
-    initLocExprSingleUse(p, n, a)
+    a = initLocExprSingleUse(p, n)
     addRdLoc(withTmpIfNeeded(p, a, needsTmp), result)
 
 import aliasanalysis
 
 proc potentialAlias(n: PNode, potentialWrites: seq[PNode]): bool =
+  result = false
   for p in potentialWrites:
     if p.aliases(n) != no or n.aliases(p) != no:
       return true
@@ -369,7 +402,7 @@ proc getPotentialWrites(n: PNode; mutate: bool; result: var seq[PNode]) =
   of nkCallKinds:
     case n.getMagic:
     of mIncl, mExcl, mInc, mDec, mAppendStrCh, mAppendStrStr, mAppendSeqElem,
-        mAddr, mNew, mNewFinalize, mWasMoved, mDestroy, mReset:
+        mAddr, mNew, mNewFinalize, mWasMoved, mDestroy:
       getPotentialWrites(n[1], true, result)
       for i in 2..<n.len:
         getPotentialWrites(n[i], mutate, result)
@@ -395,25 +428,27 @@ proc genParams(p: BProc, ri: PNode, typ: PType; result: var Rope) =
   # We must generate temporaries in cases like #14396
   # to keep the strict Left-To-Right evaluation
   var needTmp = newSeq[bool](ri.len - 1)
-  var potentialWrites: seq[PNode]
+  var potentialWrites: seq[PNode] = @[]
   for i in countdown(ri.len - 1, 1):
     if ri[i].skipTrivialIndirections.kind == nkSym:
       needTmp[i - 1] = potentialAlias(ri[i], potentialWrites)
     else:
       #if not ri[i].typ.isCompileTimeOnly:
-      var potentialReads: seq[PNode]
+      var potentialReads: seq[PNode] = @[]
       getPotentialReads(ri[i], potentialReads)
       for n in potentialReads:
         if not needTmp[i - 1]:
           needTmp[i - 1] = potentialAlias(n, potentialWrites)
       getPotentialWrites(ri[i], false, potentialWrites)
-    if ri[i].kind in {nkHiddenAddr, nkAddr}:
-      # Optimization: don't use a temp, if we would only take the address anyway
-      needTmp[i - 1] = false
+    when false:
+      # this optimization is wrong, see bug #23748
+      if ri[i].kind in {nkHiddenAddr, nkAddr}:
+        # Optimization: don't use a temp, if we would only take the address anyway
+        needTmp[i - 1] = false
 
   var oldLen = result.len
   for i in 1..<ri.len:
-    if i < typ.len:
+    if i < typ.n.len:
       assert(typ.n[i].kind == nkSym)
       let paramType = typ.n[i]
       if not paramType.typ.isCompileTimeOnly:
@@ -433,13 +468,11 @@ proc addActualSuffixForHCR(res: var Rope, module: PSym, sym: PSym) =
     res = res & "_actual".rope
 
 proc genPrefixCall(p: BProc, le, ri: PNode, d: var TLoc) =
-  var op: TLoc
   # this is a hotspot in the compiler
-  initLocExpr(p, ri[0], op)
+  var op = initLocExpr(p, ri[0])
   # getUniqueType() is too expensive here:
   var typ = skipTypes(ri[0].typ, abstractInstOwned)
   assert(typ.kind == tyProc)
-  assert(typ.len == typ.n.len)
 
   var params = newRopeAppender()
   genParams(p, ri, typ, params)
@@ -457,13 +490,11 @@ proc genClosureCall(p: BProc, le, ri: PNode, d: var TLoc) =
   const PatProc = "$1.ClE_0? $1.ClP_0($3$1.ClE_0):(($4)($1.ClP_0))($2)"
   const PatIter = "$1.ClP_0($3$1.ClE_0)" # we know the env exists
 
-  var op: TLoc
-  initLocExpr(p, ri[0], op)
+  var op = initLocExpr(p, ri[0])
 
   # getUniqueType() is too expensive here:
   var typ = skipTypes(ri[0].typ, abstractInstOwned)
   assert(typ.kind == tyProc)
-  assert(typ.len == typ.n.len)
 
   var pl = newRopeAppender()
   genParams(p, ri, typ, pl)
@@ -476,14 +507,14 @@ proc genClosureCall(p: BProc, le, ri: PNode, d: var TLoc) =
 
   let rawProc = getClosureType(p.module, typ, clHalf)
   let canRaise = p.config.exc == excGoto and canRaiseDisp(p, ri[0])
-  if typ[0] != nil:
+  if typ.returnType != nil:
     if isInvalidReturnType(p.config, typ):
       if ri.len > 1: pl.add(", ")
       # beware of 'result = p(result)'. We may need to allocate a temporary:
       if d.k in {locTemp, locNone} or not preventNrvo(p, d.lode, le, ri):
         # Great, we can use 'd':
         if d.k == locNone:
-          getTemp(p, typ[0], d, needsInit=true)
+          d = getTemp(p, typ.returnType, needsInit=true)
         elif d.k notin {locTemp} and not hasNoInit(ri):
           # reset before pass as 'result' var:
           discard "resetLoc(p, d)"
@@ -491,33 +522,29 @@ proc genClosureCall(p: BProc, le, ri: PNode, d: var TLoc) =
         genCallPattern()
         if canRaise: raiseExit(p)
       else:
-        var tmp: TLoc
-        getTemp(p, typ[0], tmp, needsInit=true)
+        var tmp: TLoc = getTemp(p, typ.returnType, needsInit=true)
         pl.add(addrLoc(p.config, tmp))
         genCallPattern()
         if canRaise: raiseExit(p)
         genAssignment(p, d, tmp, {}) # no need for deep copying
     elif isHarmlessStore(p, canRaise, d):
-      if d.k == locNone: getTemp(p, typ[0], d)
+      if d.k == locNone: d = getTemp(p, typ.returnType)
       assert(d.t != nil)        # generate an assignment to d:
-      var list: TLoc
-      initLoc(list, locCall, d.lode, OnUnknown)
+      var list: TLoc = initLoc(locCall, d.lode, OnUnknown)
       if tfIterator in typ.flags:
-        list.r = PatIter % [rdLoc(op), pl, pl.addComma, rawProc]
+        list.snippet = PatIter % [rdLoc(op), pl, pl.addComma, rawProc]
       else:
-        list.r = PatProc % [rdLoc(op), pl, pl.addComma, rawProc]
+        list.snippet = PatProc % [rdLoc(op), pl, pl.addComma, rawProc]
       genAssignment(p, d, list, {}) # no need for deep copying
       if canRaise: raiseExit(p)
     else:
-      var tmp: TLoc
-      getTemp(p, typ[0], tmp)
+      var tmp: TLoc = getTemp(p, typ.returnType)
       assert(d.t != nil)        # generate an assignment to d:
-      var list: TLoc
-      initLoc(list, locCall, d.lode, OnUnknown)
+      var list: TLoc = initLoc(locCall, d.lode, OnUnknown)
       if tfIterator in typ.flags:
-        list.r = PatIter % [rdLoc(op), pl, pl.addComma, rawProc]
+        list.snippet = PatIter % [rdLoc(op), pl, pl.addComma, rawProc]
       else:
-        list.r = PatProc % [rdLoc(op), pl, pl.addComma, rawProc]
+        list.snippet = PatProc % [rdLoc(op), pl, pl.addComma, rawProc]
       genAssignment(p, tmp, list, {})
       if canRaise: raiseExit(p)
       genAssignment(p, d, tmp, {})
@@ -527,14 +554,14 @@ proc genClosureCall(p: BProc, le, ri: PNode, d: var TLoc) =
 
 proc genOtherArg(p: BProc; ri: PNode; i: int; typ: PType; result: var Rope;
                  argsCounter: var int) =
-  if i < typ.len:
+  if i < typ.n.len:
     # 'var T' is 'T&' in C++. This means we ignore the request of
     # any nkHiddenAddr when it's a 'var T'.
     let paramType = typ.n[i]
     assert(paramType.kind == nkSym)
     if paramType.typ.isCompileTimeOnly:
       discard
-    elif typ[i].kind in {tyVar} and ri[i].kind == nkHiddenAddr:
+    elif paramType.typ.kind in {tyVar} and ri[i].kind == nkHiddenAddr:
       if argsCounter > 0: result.add ", "
       genArgNoParam(p, ri[i][0], result)
       inc argsCounter
@@ -609,7 +636,7 @@ proc genThisArg(p: BProc; ri: PNode; i: int; typ: PType; result: var Rope) =
   # for better or worse c2nim translates the 'this' argument to a 'var T'.
   # However manual wrappers may also use 'ptr T'. In any case we support both
   # for convenience.
-  internalAssert p.config, i < typ.len
+  internalAssert p.config, i < typ.n.len
   assert(typ.n[i].kind == nkSym)
   # if the parameter is lying (tyVar) and thus we required an additional deref,
   # skip the deref:
@@ -681,7 +708,7 @@ proc genPatternCall(p: BProc; ri: PNode; pat: string; typ: PType; result: var Ro
       inc j
       inc i
     of '\'':
-      var idx, stars: int
+      var idx, stars: int = 0
       if scanCppGenericSlot(pat, i, idx, stars):
         var t = resolveStarsInCppType(typ, idx, stars)
         if t == nil: result.add("void")
@@ -695,34 +722,31 @@ proc genPatternCall(p: BProc; ri: PNode; pat: string; typ: PType; result: var Ro
         result.add(substr(pat, start, i - 1))
 
 proc genInfixCall(p: BProc, le, ri: PNode, d: var TLoc) =
-  var op: TLoc
-  initLocExpr(p, ri[0], op)
+  var op = initLocExpr(p, ri[0])
   # getUniqueType() is too expensive here:
   var typ = skipTypes(ri[0].typ, abstractInst)
   assert(typ.kind == tyProc)
-  assert(typ.len == typ.n.len)
   # don't call '$' here for efficiency:
-  let pat = $ri[0].sym.loc.r
+  let pat = $ri[0].sym.loc.snippet
   internalAssert p.config, pat.len > 0
   if pat.contains({'#', '(', '@', '\''}):
     var pl = newRopeAppender()
     genPatternCall(p, ri, pat, typ, pl)
     # simpler version of 'fixupCall' that works with the pl+params combination:
     var typ = skipTypes(ri[0].typ, abstractInst)
-    if typ[0] != nil:
+    if typ.returnType != nil:
       if p.module.compileToCpp and lfSingleUse in d.flags:
         # do not generate spurious temporaries for C++! For C we're better off
         # with them to prevent undefined behaviour and because the codegen
         # is free to emit expressions multiple times!
         d.k = locCall
-        d.r = pl
+        d.snippet = pl
         excl d.flags, lfSingleUse
       else:
-        if d.k == locNone: getTemp(p, typ[0], d)
+        if d.k == locNone: d = getTemp(p, typ.returnType)
         assert(d.t != nil)        # generate an assignment to d:
-        var list: TLoc
-        initLoc(list, locCall, d.lode, OnUnknown)
-        list.r = pl
+        var list: TLoc = initLoc(locCall, d.lode, OnUnknown)
+        list.snippet = pl
         genAssignment(p, d, list, {}) # no need for deep copying
     else:
       pl.add(";\n")
@@ -732,30 +756,27 @@ proc genInfixCall(p: BProc, le, ri: PNode, d: var TLoc) =
     var argsCounter = 0
     if 1 < ri.len:
       genThisArg(p, ri, 1, typ, pl)
-    pl.add(op.r)
+    pl.add(op.snippet)
     var params = newRopeAppender()
     for i in 2..<ri.len:
-      assert(typ.len == typ.n.len)
       genOtherArg(p, ri, i, typ, params, argsCounter)
     fixupCall(p, le, ri, d, pl, params)
 
 proc genNamedParamCall(p: BProc, ri: PNode, d: var TLoc) =
   # generates a crappy ObjC call
-  var op: TLoc
-  initLocExpr(p, ri[0], op)
+  var op = initLocExpr(p, ri[0])
   var pl = "["
   # getUniqueType() is too expensive here:
   var typ = skipTypes(ri[0].typ, abstractInst)
   assert(typ.kind == tyProc)
-  assert(typ.len == typ.n.len)
 
   # don't call '$' here for efficiency:
-  let pat = $ri[0].sym.loc.r
+  let pat = $ri[0].sym.loc.snippet
   internalAssert p.config, pat.len > 0
   var start = 3
   if ' ' in pat:
     start = 1
-    pl.add(op.r)
+    pl.add(op.snippet)
     if ri.len > 1:
       pl.add(": ")
       genArg(p, ri[1], typ.n[1].sym, ri, pl)
@@ -764,13 +785,12 @@ proc genNamedParamCall(p: BProc, ri: PNode, d: var TLoc) =
     if ri.len > 1:
       genArg(p, ri[1], typ.n[1].sym, ri, pl)
       pl.add(" ")
-    pl.add(op.r)
+    pl.add(op.snippet)
     if ri.len > 2:
       pl.add(": ")
       genArg(p, ri[2], typ.n[2].sym, ri, pl)
   for i in start..<ri.len:
-    assert(typ.len == typ.n.len)
-    if i >= typ.len:
+    if i >= typ.n.len:
       internalError(p.config, ri.info, "varargs for objective C method?")
     assert(typ.n[i].kind == nkSym)
     var param = typ.n[i].sym
@@ -778,31 +798,29 @@ proc genNamedParamCall(p: BProc, ri: PNode, d: var TLoc) =
     pl.add(param.name.s)
     pl.add(": ")
     genArg(p, ri[i], param, ri, pl)
-  if typ[0] != nil:
+  if typ.returnType != nil:
     if isInvalidReturnType(p.config, typ):
       if ri.len > 1: pl.add(" ")
       # beware of 'result = p(result)'. We always allocate a temporary:
       if d.k in {locTemp, locNone}:
         # We already got a temp. Great, special case it:
-        if d.k == locNone: getTemp(p, typ[0], d, needsInit=true)
+        if d.k == locNone: d = getTemp(p, typ.returnType, needsInit=true)
         pl.add("Result: ")
         pl.add(addrLoc(p.config, d))
         pl.add("];\n")
         line(p, cpsStmts, pl)
       else:
-        var tmp: TLoc
-        getTemp(p, typ[0], tmp, needsInit=true)
+        var tmp: TLoc = getTemp(p, typ.returnType, needsInit=true)
         pl.add(addrLoc(p.config, tmp))
         pl.add("];\n")
         line(p, cpsStmts, pl)
         genAssignment(p, d, tmp, {}) # no need for deep copying
     else:
       pl.add("]")
-      if d.k == locNone: getTemp(p, typ[0], d)
+      if d.k == locNone: d = getTemp(p, typ.returnType)
       assert(d.t != nil)        # generate an assignment to d:
-      var list: TLoc
-      initLoc(list, locCall, ri, OnUnknown)
-      list.r = pl
+      var list: TLoc = initLoc(locCall, ri, OnUnknown)
+      list.snippet = pl
       genAssignment(p, d, list, {}) # no need for deep copying
   else:
     pl.add("];\n")

compiler/ccgliterals.nim

@@ -36,50 +36,83 @@ proc genStringLiteralDataOnlyV1(m: BModule, s: string; result: var Rope) =
   cgsym(m, "TGenericSeq")
   let tmp = getTempName(m)
   result.add tmp
-  m.s[cfsStrData].addf("STRING_LITERAL($1, $2, $3);$n",
-       [tmp, makeCString(s), rope(s.len)])
+  var res = newBuilder("")
+  res.addVarWithTypeAndInitializer(AlwaysConst, name = tmp):
+    res.addSimpleStruct(m, name = "", baseType = ""):
+      res.addField(name = "Sup", typ = "TGenericSeq")
+      res.addArrayField(name = "data", elementType = "NIM_CHAR", len = s.len + 1)
+  do:
+    var strInit: StructInitializer
+    res.addStructInitializer(strInit, kind = siOrderedStruct):
+      res.addField(strInit, name = "Sup"):
+        var seqInit: StructInitializer
+        res.addStructInitializer(seqInit, kind = siOrderedStruct):
+          res.addField(seqInit, name = "len"):
+            res.add(rope(s.len))
+          res.addField(seqInit, name = "reserved"):
+            res.add(cCast("NI", bitOr(cCast("NU", rope(s.len)), "NIM_STRLIT_FLAG")))
+      res.addField(strInit, name = "data"):
+        res.add(makeCString(s))
+  m.s[cfsStrData].add(res)
 
 proc genStringLiteralV1(m: BModule; n: PNode; result: var Rope) =
   if s.isNil:
-    appcg(m, result, "((#NimStringDesc*) NIM_NIL)", [])
+    result.add(cCast(ptrType(cgsymValue(m, "NimStringDesc")), "NIM_NIL"))
   else:
     let id = nodeTableTestOrSet(m.dataCache, n, m.labels)
+    var name: string = ""
     if id == m.labels:
       # string literal not found in the cache:
-      appcg(m, result, "((#NimStringDesc*) &", [])
-      genStringLiteralDataOnlyV1(m, n.strVal, result)
-      result.add ")"
+      genStringLiteralDataOnlyV1(m, n.strVal, name)
     else:
-      appcg(m, result, "((#NimStringDesc*) &$1$2)",
-                      [m.tmpBase, id])
+      name = m.tmpBase & $id
+    result.add(cCast(ptrType(cgsymValue(m, "NimStringDesc")), cAddr(name)))
 
 # ------ Version 2: destructor based strings and seqs -----------------------
 
 proc genStringLiteralDataOnlyV2(m: BModule, s: string; result: Rope; isConst: bool) =
-  m.s[cfsStrData].addf("static $4 struct {$n" &
-       "  NI cap; NIM_CHAR data[$2+1];$n" &
-       "} $1 = { $2 | NIM_STRLIT_FLAG, $3 };$n",
-       [result, rope(s.len), makeCString(s),
-       rope(if isConst: "const" else: "")])
+  var res = newBuilder("")
+  res.addVarWithTypeAndInitializer(
+      if isConst: AlwaysConst else: Global,
+      name = result):
+    res.addSimpleStruct(m, name = "", baseType = ""):
+      res.addField(name = "cap", typ = "NI")
+      res.addArrayField(name = "data", elementType = "NIM_CHAR", len = s.len + 1)
+  do:
+    var structInit: StructInitializer
+    res.addStructInitializer(structInit, kind = siOrderedStruct):
+      res.addField(structInit, name = "cap"):
+        res.add(bitOr(rope(s.len), "NIM_STRLIT_FLAG"))
+      res.addField(structInit, name = "data"):
+        res.add(makeCString(s))
+  m.s[cfsStrData].add(res)
 
 proc genStringLiteralV2(m: BModule; n: PNode; isConst: bool; result: var Rope) =
   let id = nodeTableTestOrSet(m.dataCache, n, m.labels)
+  var litName: string
   if id == m.labels:
-    let pureLit = getTempName(m)
-    genStringLiteralDataOnlyV2(m, n.strVal, pureLit, isConst)
-    let tmp = getTempName(m)
-    result.add tmp
     cgsym(m, "NimStrPayload")
     cgsym(m, "NimStringV2")
     # string literal not found in the cache:
-    m.s[cfsStrData].addf("static $4 NimStringV2 $1 = {$2, (NimStrPayload*)&$3};$n",
-          [tmp, rope(n.strVal.len), pureLit, rope(if isConst: "const" else: "")])
+    litName = getTempName(m)
+    genStringLiteralDataOnlyV2(m, n.strVal, litName, isConst)
   else:
-    let tmp = getTempName(m)
-    result.add tmp
-    m.s[cfsStrData].addf("static $4 NimStringV2 $1 = {$2, (NimStrPayload*)&$3};$n",
-          [tmp, rope(n.strVal.len), m.tmpBase & rope(id),
-          rope(if isConst: "const" else: "")])
+    litName = m.tmpBase & $id
+  let tmp = getTempName(m)
+  result.add tmp
+  var res = newBuilder("")
+  res.addVarWithTypeAndInitializer(
+      if isConst: AlwaysConst else: Global,
+      name = tmp):
+    res.add("NimStringV2")
+  do:
+    var strInit: StructInitializer
+    res.addStructInitializer(strInit, kind = siOrderedStruct):
+      res.addField(strInit, name = "len"):
+        res.add(rope(n.strVal.len))
+      res.addField(strInit, name = "p"):
+        res.add(cCast(ptrType("NimStrPayload"), cAddr(litName)))
+  m.s[cfsStrData].add(res)
 
 proc genStringLiteralV2Const(m: BModule; n: PNode; isConst: bool; result: var Rope) =
   let id = nodeTableTestOrSet(m.dataCache, n, m.labels)
@@ -92,7 +125,12 @@ proc genStringLiteralV2Const(m: BModule; n: PNode; isConst: bool; result: var Ro
     genStringLiteralDataOnlyV2(m, n.strVal, pureLit, isConst)
   else:
     pureLit = m.tmpBase & rope(id)
-  result.addf "{$1, (NimStrPayload*)&$2}", [rope(n.strVal.len), pureLit]
+  var strInit: StructInitializer
+  result.addStructInitializer(strInit, kind = siOrderedStruct):
+    result.addField(strInit, name = "len"):
+      result.add(rope(n.strVal.len))
+    result.addField(strInit, name = "p"):
+      result.add(cCast(ptrType("NimStrPayload"), cAddr(pureLit)))
 
 # ------ Version selector ---------------------------------------------------
 
@@ -108,7 +146,7 @@ proc genStringLiteralDataOnly(m: BModule; s: string; info: TLineInfo;
     localError(m.config, info, "cannot determine how to produce code for string literal")
 
 proc genNilStringLiteral(m: BModule; info: TLineInfo; result: var Rope) =
-  appcg(m, result, "((#NimStringDesc*) NIM_NIL)", [])
+  result.add(cCast(ptrType(cgsymValue(m, "NimStringDesc")), "NIM_NIL"))
 
 proc genStringLiteral(m: BModule; n: PNode; result: var Rope) =
   case detectStrVersion(m)

compiler/ccgreset.nim

@@ -24,10 +24,10 @@ proc specializeResetN(p: BProc, accessor: Rope, n: PNode;
   of nkRecCase:
     if (n[0].kind != nkSym): internalError(p.config, n.info, "specializeResetN")
     let disc = n[0].sym
-    if disc.loc.r == "": fillObjectFields(p.module, typ)
+    if disc.loc.snippet == "": fillObjectFields(p.module, typ)
     if disc.loc.t == nil:
       internalError(p.config, n.info, "specializeResetN()")
-    lineF(p, cpsStmts, "switch ($1.$2) {$n", [accessor, disc.loc.r])
+    lineF(p, cpsStmts, "switch ($1.$2) {$n", [accessor, disc.loc.snippet])
     for i in 1..<n.len:
       let branch = n[i]
       assert branch.kind in {nkOfBranch, nkElse}
@@ -38,14 +38,14 @@ proc specializeResetN(p: BProc, accessor: Rope, n: PNode;
       specializeResetN(p, accessor, lastSon(branch), typ)
       lineF(p, cpsStmts, "break;$n", [])
     lineF(p, cpsStmts, "} $n", [])
-    specializeResetT(p, "$1.$2" % [accessor, disc.loc.r], disc.loc.t)
+    specializeResetT(p, "$1.$2" % [accessor, disc.loc.snippet], disc.loc.t)
   of nkSym:
     let field = n.sym
     if field.typ.kind == tyVoid: return
-    if field.loc.r == "": fillObjectFields(p.module, typ)
+    if field.loc.snippet == "": fillObjectFields(p.module, typ)
     if field.loc.t == nil:
       internalError(p.config, n.info, "specializeResetN()")
-    specializeResetT(p, "$1.$2" % [accessor, field.loc.r], field.loc.t)
+    specializeResetT(p, "$1.$2" % [accessor, field.loc.snippet], field.loc.t)
   else: internalError(p.config, n.info, "specializeResetN()")
 
 proc specializeResetT(p: BProc, accessor: Rope, typ: PType) =
@@ -54,25 +54,23 @@ proc specializeResetT(p: BProc, accessor: Rope, typ: PType) =
   case typ.kind
   of tyGenericInst, tyGenericBody, tyTypeDesc, tyAlias, tyDistinct, tyInferred,
      tySink, tyOwned:
-    specializeResetT(p, accessor, lastSon(typ))
+    specializeResetT(p, accessor, skipModifier(typ))
   of tyArray:
-    let arraySize = lengthOrd(p.config, typ[0])
-    var i: TLoc
-    getTemp(p, getSysType(p.module.g.graph, unknownLineInfo, tyInt), i)
+    let arraySize = lengthOrd(p.config, typ.indexType)
+    var i: TLoc = getTemp(p, getSysType(p.module.g.graph, unknownLineInfo, tyInt))
     linefmt(p, cpsStmts, "for ($1 = 0; $1 < $2; $1++) {$n",
-            [i.r, arraySize])
-    specializeResetT(p, ropecg(p.module, "$1[$2]", [accessor, i.r]), typ[1])
+            [i.snippet, arraySize])
+    specializeResetT(p, ropecg(p.module, "$1[$2]", [accessor, i.snippet]), typ.elementType)
     lineF(p, cpsStmts, "}$n", [])
   of tyObject:
-    for i in 0..<typ.len:
-      var x = typ[i]
-      if x != nil: x = x.skipTypes(skipPtrs)
-      specializeResetT(p, accessor.parentObj(p.module), x)
+    var x = typ.baseClass
+    if x != nil: x = x.skipTypes(skipPtrs)
+    specializeResetT(p, accessor.parentObj(p.module), x)
     if typ.n != nil: specializeResetN(p, accessor, typ.n, typ)
   of tyTuple:
     let typ = getUniqueType(typ)
-    for i in 0..<typ.len:
-      specializeResetT(p, ropecg(p.module, "$1.Field$2", [accessor, i]), typ[i])
+    for i, a in typ.ikids:
+      specializeResetT(p, ropecg(p.module, "$1.Field$2", [accessor, i]), a)
 
   of tyString, tyRef, tySequence:
     lineCg(p, cpsStmts, "#unsureAsgnRef((void**)&$1, NIM_NIL);$n", [accessor])
@@ -95,12 +93,12 @@ proc specializeResetT(p: BProc, accessor: Rope, typ: PType) =
     of ctInt8, ctInt16, ctInt32, ctInt64:
       lineCg(p, cpsStmts, "$1 = 0;$n", [accessor])
     else:
-      doAssert false, "unexpected set type kind"
-  of {tyNone, tyEmpty, tyNil, tyUntyped, tyTyped, tyGenericInvocation,
+      raiseAssert "unexpected set type kind"
+  of tyNone, tyEmpty, tyNil, tyUntyped, tyTyped, tyGenericInvocation,
       tyGenericParam, tyOrdinal, tyOpenArray, tyForward, tyVarargs,
-      tyUncheckedArray, tyProxy, tyBuiltInTypeClass, tyUserTypeClass,
+      tyUncheckedArray, tyError, tyBuiltInTypeClass, tyUserTypeClass,
       tyUserTypeClassInst, tyCompositeTypeClass, tyAnd, tyOr, tyNot,
-      tyAnything, tyStatic, tyFromExpr, tyConcept, tyVoid, tyIterable}:
+      tyAnything, tyStatic, tyFromExpr, tyConcept, tyVoid, tyIterable:
     discard
 
 proc specializeReset(p: BProc, a: TLoc) =

compiler/ccgstmts.nim

@@ -50,6 +50,7 @@ proc isAssignedImmediately(conf: ConfigRef; n: PNode): bool {.inline.} =
     result = true
 
 proc inExceptBlockLen(p: BProc): int =
+  result = 0
   for x in p.nestedTryStmts:
     if x.inExcept: result.inc
 
@@ -71,7 +72,6 @@ template startBlock(p: BProc, start: FormatStr = "{$n",
 proc endBlock(p: BProc)
 
 proc genVarTuple(p: BProc, n: PNode) =
-  var tup, field: TLoc
   if n.kind != nkVarTuple: internalError(p.config, n.info, "genVarTuple")
 
   # if we have a something that's been captured, use the lowering instead:
@@ -83,7 +83,7 @@ proc genVarTuple(p: BProc, n: PNode) =
   # check only the first son
   var forHcr = treatGlobalDifferentlyForHCR(p.module, n[0].sym)
   let hcrCond = if forHcr: getTempName(p.module) else: ""
-  var hcrGlobals: seq[tuple[loc: TLoc, tp: Rope]]
+  var hcrGlobals: seq[tuple[loc: TLoc, tp: Rope]] = @[]
   # determine if the tuple is constructed at top-level scope or inside of a block (if/while/block)
   let isGlobalInBlock = forHcr and p.blocks.len > 2
   # do not close and reopen blocks if this is a 'global' but inside of a block (if/while/block)
@@ -95,7 +95,7 @@ proc genVarTuple(p: BProc, n: PNode) =
     startBlock(p)
 
   genLineDir(p, n)
-  initLocExpr(p, n[^1], tup)
+  var tup = initLocExpr(p, n[^1])
   var t = tup.t.skipTypes(abstractInst)
   for i in 0..<n.len-2:
     let vn = n[i]
@@ -108,12 +108,12 @@ proc genVarTuple(p: BProc, n: PNode) =
     else:
       assignLocalVar(p, vn)
       initLocalVar(p, v, immediateAsgn=isAssignedImmediately(p.config, n[^1]))
-    initLoc(field, locExpr, vn, tup.storage)
+    var field = initLoc(locExpr, vn, tup.storage)
     if t.kind == tyTuple:
-      field.r = "$1.Field$2" % [rdLoc(tup), rope(i)]
+      field.snippet = "$1.Field$2" % [rdLoc(tup), rope(i)]
     else:
       if t.n[i].kind != nkSym: internalError(p.config, n.info, "genVarTuple")
-      field.r = "$1.$2" % [rdLoc(tup), mangleRecFieldName(p.module, t.n[i].sym)]
+      field.snippet = "$1.$2" % [rdLoc(tup), mangleRecFieldName(p.module, t.n[i].sym)]
     putLocIntoDest(p, v.loc, field)
     if forHcr or isGlobalInBlock:
       hcrGlobals.add((loc: v.loc, tp: "NULL"))
@@ -128,7 +128,7 @@ proc genVarTuple(p: BProc, n: PNode) =
     lineCg(p, cpsLocals, "NIM_BOOL $1 = NIM_FALSE;$n", [hcrCond])
     for curr in hcrGlobals:
       lineCg(p, cpsLocals, "$1 |= hcrRegisterGlobal($4, \"$2\", sizeof($3), $5, (void**)&$2);$N",
-              [hcrCond, curr.loc.r, rdLoc(curr.loc), getModuleDllPath(p.module, n[0].sym), curr.tp])
+              [hcrCond, curr.loc.snippet, rdLoc(curr.loc), getModuleDllPath(p.module, n[0].sym), curr.tp])
 
 
 proc loadInto(p: BProc, le, ri: PNode, a: var TLoc) {.inline.} =
@@ -169,7 +169,7 @@ proc endBlock(p: BProc, blockEnd: Rope) =
 proc endBlock(p: BProc) =
   let topBlock = p.blocks.len - 1
   let frameLen = p.blocks[topBlock].frameLen
-  var blockEnd: Rope
+  var blockEnd: Rope = ""
   if frameLen > 0:
     blockEnd.addf("FR_.len-=$1;$n", [frameLen.rope])
   if p.blocks[topBlock].label.len != 0:
@@ -244,8 +244,7 @@ proc genGotoState(p: BProc, n: PNode) =
   # switch (x.state) {
   #   case 0: goto STATE0;
   # ...
-  var a: TLoc
-  initLocExpr(p, n[0], a)
+  var a: TLoc = initLocExpr(p, n[0])
   lineF(p, cpsStmts, "switch ($1) {$n", [rdLoc(a)])
   p.flags.incl beforeRetNeeded
   lineF(p, cpsStmts, "case -1:$n", [])
@@ -264,15 +263,15 @@ proc genGotoState(p: BProc, n: PNode) =
 
 proc genBreakState(p: BProc, n: PNode, d: var TLoc) =
   var a: TLoc
-  initLoc(d, locExpr, n, OnUnknown)
+  d = initLoc(locExpr, n, OnUnknown)
 
   if n[0].kind == nkClosure:
-    initLocExpr(p, n[0][1], a)
-    d.r = "(((NI*) $1)[1] < 0)" % [rdLoc(a)]
+    a = initLocExpr(p, n[0][1])
+    d.snippet = "(((NI*) $1)[1] < 0)" % [rdLoc(a)]
   else:
-    initLocExpr(p, n[0], a)
+    a = initLocExpr(p, n[0])
     # the environment is guaranteed to contain the 'state' field at offset 1:
-    d.r = "((((NI*) $1.ClE_0)[1]) < 0)" % [rdLoc(a)]
+    d.snippet = "((((NI*) $1.ClE_0)[1]) < 0)" % [rdLoc(a)]
 
 proc genGotoVar(p: BProc; value: PNode) =
   if value.kind notin {nkCharLit..nkUInt64Lit}:
@@ -280,7 +279,7 @@ proc genGotoVar(p: BProc; value: PNode) =
   else:
     lineF(p, cpsStmts, "goto NIMSTATE_$#;$n", [value.intVal.rope])
 
-proc genBracedInit(p: BProc, n: PNode; isConst: bool; optionalType: PType; result: var Rope)
+proc genBracedInit(p: BProc, n: PNode; isConst: bool; optionalType: PType; result: var Builder)
 
 proc potentialValueInit(p: BProc; v: PSym; value: PNode; result: var Rope) =
   if lfDynamicLib in v.loc.flags or sfThread in v.flags or p.hcrOn:
@@ -290,14 +289,32 @@ proc potentialValueInit(p: BProc; v: PSym; value: PNode; result: var Rope) =
     #echo "New code produced for ", v.name.s, " ", p.config $ value.info
     genBracedInit(p, value, isConst = false, v.typ, result)
 
-proc genCppVarForCtor(p: BProc, v: PSym; vn, value: PNode; decl: var Rope) =
-  var params = newRopeAppender()
+proc genCppParamsForCtor(p: BProc; call: PNode; didGenTemp: var bool): string =
+  result = ""
   var argsCounter = 0
-  let typ = skipTypes(value[0].typ, abstractInst)
+  let typ = skipTypes(call[0].typ, abstractInst)
   assert(typ.kind == tyProc)
-  for i in 1..<value.len:
-    assert(typ.len == typ.n.len)
-    genOtherArg(p, value, i, typ, params, argsCounter)
+  for i in 1..<call.len:
+    #if it's a type we can just generate here another initializer as we are in an initializer context
+    if call[i].kind == nkCall and call[i][0].kind == nkSym and call[i][0].sym.kind == skType:
+      if argsCounter > 0: result.add ","
+      result.add genCppInitializer(p.module, p, call[i][0].sym.typ, didGenTemp)
+    else:
+      #We need to test for temp in globals, see: #23657
+      let param =
+        if typ[i].kind in {tyVar} and call[i].kind == nkHiddenAddr:
+          call[i][0]
+        else:
+          call[i]
+      if param.kind != nkBracketExpr or param.typ.kind in
+        {tyRef, tyPtr, tyUncheckedArray, tyArray, tyOpenArray,
+          tyVarargs, tySequence, tyString, tyCstring, tyTuple}:
+        let tempLoc = initLocExprSingleUse(p, param)
+        didGenTemp = didGenTemp or tempLoc.k == locTemp
+      genOtherArg(p, call, i, typ, result, argsCounter)
+
+proc genCppVarForCtor(p: BProc; call: PNode; decl: var Rope, didGenTemp: var bool) =
+  let params = genCppParamsForCtor(p, call, didGenTemp)
   if params.len == 0:
     decl = runtimeFormat("$#;\n", [decl])
   else:
@@ -324,7 +341,14 @@ proc genSingleVar(p: BProc, v: PSym; vn, value: PNode) =
       # v.owner.kind != skModule:
       targetProc = p.module.preInitProc
     if isCppCtorCall and not containsHiddenPointer(v.typ):
-      callGlobalVarCppCtor(targetProc, v, vn, value)
+      var didGenTemp = false
+      callGlobalVarCppCtor(targetProc, v, vn, value, didGenTemp)
+      if didGenTemp:
+        message(p.config, vn.info, warnGlobalVarConstructorTemporary, vn.sym.name.s)
+        #We fail to call the constructor in the global scope so we do the call inside the main proc
+        assignGlobalVar(targetProc, vn, valueAsRope)
+        var loc = initLocExprSingleUse(targetProc, value)
+        genAssignment(targetProc, v.loc, loc, {})
     else:
       assignGlobalVar(targetProc, vn, valueAsRope)
 
@@ -341,7 +365,7 @@ proc genSingleVar(p: BProc, v: PSym; vn, value: PNode) =
       # Only do this for complex types that may need a call to `objectInit`
       if sfThread in v.flags and emulatedThreadVars(p.config) and
         isComplexValueType(v.typ):
-        initLocExprSingleUse(p.module.preInitProc, vn, loc)
+        loc = initLocExprSingleUse(p.module.preInitProc, vn)
       genObjectInit(p.module.preInitProc, cpsInit, v.typ, loc, constructObj)
     # Alternative construction using default constructor (which may zeromem):
     # if sfImportc notin v.flags: constructLoc(p.module.preInitProc, v.loc)
@@ -359,11 +383,15 @@ proc genSingleVar(p: BProc, v: PSym; vn, value: PNode) =
       var decl = localVarDecl(p, vn)
       var tmp: TLoc
       if isCppCtorCall:
-        genCppVarForCtor(p, v, vn, value, decl)
+        var didGenTemp = false
+        genCppVarForCtor(p, value, decl, didGenTemp)
         line(p, cpsStmts, decl)
       else:
-        initLocExprSingleUse(p, value, tmp)
-        lineF(p, cpsStmts, "$# = $#;\n", [decl, tmp.rdLoc])
+        tmp = initLocExprSingleUse(p, value)
+        if value.kind == nkEmpty:
+          lineF(p, cpsStmts, "$#;\n", [decl])
+        else:
+          lineF(p, cpsStmts, "$# = $#;\n", [decl, tmp.rdLoc])
       return
     assignLocalVar(p, vn)
     initLocalVar(p, v, imm)
@@ -377,7 +405,7 @@ proc genSingleVar(p: BProc, v: PSym; vn, value: PNode) =
     # put it in the locals section - mainly because of loops which
     # use the var in a call to resetLoc() in the statements section
     lineCg(targetProc, cpsLocals, "hcrRegisterGlobal($3, \"$1\", sizeof($2), $4, (void**)&$1);$n",
-           [v.loc.r, rdLoc(v.loc), getModuleDllPath(p.module, v), traverseProc])
+           [v.loc.snippet, rdLoc(v.loc), getModuleDllPath(p.module, v), traverseProc])
     # nothing special left to do later on - let's avoid closing and reopening blocks
     forHcr = false
 
@@ -386,7 +414,7 @@ proc genSingleVar(p: BProc, v: PSym; vn, value: PNode) =
   # be able to re-run it but without the top level code - just the init of globals
   if forHcr:
     lineCg(targetProc, cpsStmts, "if (hcrRegisterGlobal($3, \"$1\", sizeof($2), $4, (void**)&$1))$N",
-           [v.loc.r, rdLoc(v.loc), getModuleDllPath(p.module, v), traverseProc])
+           [v.loc.snippet, rdLoc(v.loc), getModuleDllPath(p.module, v), traverseProc])
     startBlock(targetProc)
   if value.kind != nkEmpty and valueAsRope.len == 0:
     genLineDir(targetProc, vn)
@@ -408,8 +436,7 @@ proc genSingleVar(p: BProc, a: PNode) =
 
 proc genClosureVar(p: BProc, a: PNode) =
   var immediateAsgn = a[2].kind != nkEmpty
-  var v: TLoc
-  initLocExpr(p, a[0], v)
+  var v: TLoc = initLocExpr(p, a[0])
   genLineDir(p, a)
   if immediateAsgn:
     loadInto(p, a[0], a[2], v)
@@ -444,7 +471,7 @@ proc genIf(p: BProc, n: PNode, d: var TLoc) =
     a: TLoc
     lelse: TLabel
   if not isEmptyType(n.typ) and d.k == locNone:
-    getTemp(p, n.typ, d)
+    d = getTemp(p, n.typ)
   genLineDir(p, n)
   let lend = getLabel(p)
   for it in n.sons:
@@ -452,7 +479,7 @@ proc genIf(p: BProc, n: PNode, d: var TLoc) =
     if d.k == locTemp and isEmptyType(n.typ): d.k = locNone
     if it.len == 2:
       startBlock(p)
-      initLocExprSingleUse(p, it[0], a)
+      a = initLocExprSingleUse(p, it[0])
       lelse = getLabel(p)
       inc(p.labels)
       lineF(p, cpsStmts, "if (!$1) goto $2;$n",
@@ -520,7 +547,7 @@ proc genComputedGoto(p: BProc; n: PNode) =
   # wrapped inside stmt lists by inject destructors won't be recognised
   let n = n.flattenStmts()
   var casePos = -1
-  var arraySize: int
+  var arraySize: int = 0
   for i in 0..<n.len:
     let it = n[i]
     if it.kind == nkCaseStmt:
@@ -554,8 +581,7 @@ proc genComputedGoto(p: BProc; n: PNode) =
     genStmts(p, n[j])
 
   let caseStmt = n[casePos]
-  var a: TLoc
-  initLocExpr(p, caseStmt[0], a)
+  var a: TLoc = initLocExpr(p, caseStmt[0])
   # first goto:
   lineF(p, cpsStmts, "goto *$#[$#];$n", [tmp, a.rdLoc])
 
@@ -593,8 +619,7 @@ proc genComputedGoto(p: BProc; n: PNode) =
       else:
         genStmts(p, it)
 
-    var a: TLoc
-    initLocExpr(p, caseStmt[0], a)
+    var a: TLoc = initLocExpr(p, caseStmt[0])
     lineF(p, cpsStmts, "goto *$#[$#];$n", [tmp, a.rdLoc])
     endBlock(p)
 
@@ -622,7 +647,7 @@ proc genWhileStmt(p: BProc, t: PNode) =
     else:
       p.breakIdx = startBlock(p, "while (1) {$n")
       p.blocks[p.breakIdx].isLoop = true
-      initLocExpr(p, t[0], a)
+      a = initLocExpr(p, t[0])
       if (t[0].kind != nkIntLit) or (t[0].intVal == 0):
         lineF(p, cpsStmts, "if (!$1) goto ", [rdLoc(a)])
         assignLabel(p.blocks[p.breakIdx], p.s(cpsStmts))
@@ -641,7 +666,7 @@ proc genBlock(p: BProc, n: PNode, d: var TLoc) =
     # bug #4505: allocate the temp in the outer scope
     # so that it can escape the generated {}:
     if d.k == locNone:
-      getTemp(p, n.typ, d)
+      d = getTemp(p, n.typ)
     d.flags.incl(lfEnforceDeref)
   preserveBreakIdx:
     p.breakIdx = startBlock(p)
@@ -661,14 +686,13 @@ proc genParForStmt(p: BProc, t: PNode) =
 
   preserveBreakIdx:
     let forLoopVar = t[0].sym
-    var rangeA, rangeB: TLoc
     assignLocalVar(p, t[0])
     #initLoc(forLoopVar.loc, locLocalVar, forLoopVar.typ, onStack)
     #discard mangleName(forLoopVar)
     let call = t[1]
     assert(call.len == 4 or call.len == 5)
-    initLocExpr(p, call[1], rangeA)
-    initLocExpr(p, call[2], rangeB)
+    var rangeA = initLocExpr(p, call[1])
+    var rangeB = initLocExpr(p, call[2])
 
     # $n at the beginning because of #9710
     if call.len == 4: # procName(a, b, annotation)
@@ -685,8 +709,7 @@ proc genParForStmt(p: BProc, t: PNode) =
                     rangeA.rdLoc, rangeB.rdLoc,
                     call[3].getStr.rope])
     else: # `||`(a, b, step, annotation)
-      var step: TLoc
-      initLocExpr(p, call[3], step)
+      var step: TLoc = initLocExpr(p, call[3])
       lineF(p, cpsStmts, "$n#pragma omp $5$n" &
                     "for ($1 = $2; $1 <= $3; $1 += $4)",
                     [forLoopVar.loc.rdLoc,
@@ -732,6 +755,18 @@ proc raiseExit(p: BProc) =
       lineCg(p, cpsStmts, "if (NIM_UNLIKELY(*nimErr_)) goto LA$1_;$n",
         [p.nestedTryStmts[^1].label])
 
+proc raiseExitCleanup(p: BProc, destroy: string) =
+  assert p.config.exc == excGoto
+  if nimErrorFlagDisabled notin p.flags:
+    p.flags.incl nimErrorFlagAccessed
+    if p.nestedTryStmts.len == 0:
+      p.flags.incl beforeRetNeeded
+      # easy case, simply goto 'ret':
+      lineCg(p, cpsStmts, "if (NIM_UNLIKELY(*nimErr_)) {$1; goto BeforeRet_;}$n", [destroy])
+    else:
+      lineCg(p, cpsStmts, "if (NIM_UNLIKELY(*nimErr_)) {$2; goto LA$1_;}$n",
+        [p.nestedTryStmts[^1].label, destroy])
+
 proc finallyActions(p: BProc) =
   if p.config.exc != excGoto and p.nestedTryStmts.len > 0 and p.nestedTryStmts[^1].inExcept:
     # if the current try stmt have a finally block,
@@ -756,16 +791,19 @@ proc raiseInstr(p: BProc; result: var Rope) =
 
 proc genRaiseStmt(p: BProc, t: PNode) =
   if t[0].kind != nkEmpty:
-    var a: TLoc
-    initLocExprSingleUse(p, t[0], a)
+    var a: TLoc = initLocExprSingleUse(p, t[0])
     finallyActions(p)
     var e = rdLoc(a)
     discard getTypeDesc(p.module, t[0].typ)
     var typ = skipTypes(t[0].typ, abstractPtrs)
-    # XXX For reasons that currently escape me, this is only required by the new
-    # C++ based exception handling:
-    if p.config.exc == excCpp:
+    case p.config.exc
+    of excCpp:
       blockLeaveActions(p, howManyTrys = 0, howManyExcepts = p.inExceptBlockLen)
+    of excGoto:
+      blockLeaveActions(p, howManyTrys = 0,
+        howManyExcepts = (if p.nestedTryStmts.len > 0 and p.nestedTryStmts[^1].inExcept: 1 else: 0))
+    else:
+      discard
     genLineDir(p, t)
     if isImportedException(typ, p.config):
       lineF(p, cpsStmts, "throw $1;$n", [e])
@@ -787,12 +825,12 @@ template genCaseGenericBranch(p: BProc, b: PNode, e: TLoc,
   var x, y: TLoc
   for i in 0..<b.len - 1:
     if b[i].kind == nkRange:
-      initLocExpr(p, b[i][0], x)
-      initLocExpr(p, b[i][1], y)
+      x = initLocExpr(p, b[i][0])
+      y = initLocExpr(p, b[i][1])
       lineCg(p, cpsStmts, rangeFormat,
            [rdCharLoc(e), rdCharLoc(x), rdCharLoc(y), labl])
     else:
-      initLocExpr(p, b[i], x)
+      x = initLocExpr(p, b[i])
       lineCg(p, cpsStmts, eqFormat, [rdCharLoc(e), rdCharLoc(x), labl])
 
 proc genCaseSecondPass(p: BProc, t: PNode, d: var TLoc,
@@ -834,8 +872,7 @@ template genIfForCaseUntil(p: BProc, t: PNode, d: var TLoc,
 
 template genCaseGeneric(p: BProc, t: PNode, d: var TLoc,
                     rangeFormat, eqFormat: FormatStr) =
-  var a: TLoc
-  initLocExpr(p, t[0], a)
+  var a: TLoc = initLocExpr(p, t[0])
   var lend = genIfForCaseUntil(p, t, d, rangeFormat, eqFormat, t.len-1, a)
   fixLabel(p, lend)
 
@@ -845,8 +882,8 @@ proc genCaseStringBranch(p: BProc, b: PNode, e: TLoc, labl: TLabel,
   var x: TLoc
   for i in 0..<b.len - 1:
     assert(b[i].kind != nkRange)
-    initLocExpr(p, b[i], x)
-    var j: int
+    x = initLocExpr(p, b[i])
+    var j: int = 0
     case b[i].kind
     of nkStrLit..nkTripleStrLit:
       j = int(hashString(p.config, b[i].strVal) and high(branches))
@@ -869,8 +906,7 @@ proc genStringCase(p: BProc, t: PNode, stringKind: TTypeKind, d: var TLoc) =
     var bitMask = math.nextPowerOfTwo(strings) - 1
     var branches: seq[Rope]
     newSeq(branches, bitMask + 1)
-    var a: TLoc
-    initLocExpr(p, t[0], a) # fist pass: generate ifs+goto:
+    var a: TLoc = initLocExpr(p, t[0]) # first pass: generate ifs+goto:
     var labId = p.labels
     for i in 1..<t.len:
       inc(p.labels)
@@ -906,6 +942,7 @@ proc genStringCase(p: BProc, t: PNode, stringKind: TTypeKind, d: var TLoc) =
       genCaseGeneric(p, t, d, "", "if (#eqStrings($1, $2)) goto $3;$n")
 
 proc branchHasTooBigRange(b: PNode): bool =
+  result = false
   for it in b:
     # last son is block
     if (it.kind == nkRange) and
@@ -913,6 +950,7 @@ proc branchHasTooBigRange(b: PNode): bool =
       return true
 
 proc ifSwitchSplitPoint(p: BProc, n: PNode): int =
+  result = 0
   for i in 1..<n.len:
     var branch = n[i]
     var stmtBlock = lastSon(branch)
@@ -948,8 +986,7 @@ proc genOrdinalCase(p: BProc, n: PNode, d: var TLoc) =
   var splitPoint = ifSwitchSplitPoint(p, n)
 
   # generate if part (might be empty):
-  var a: TLoc
-  initLocExpr(p, n[0], a)
+  var a: TLoc = initLocExpr(p, n[0])
   var lend = if splitPoint > 0: genIfForCaseUntil(p, n, d,
                     rangeFormat = "if ($1 >= $2 && $1 <= $3) goto $4;$n",
                     eqFormat = "if ($1 == $2) goto $3;$n",
@@ -982,7 +1019,7 @@ proc genOrdinalCase(p: BProc, n: PNode, d: var TLoc) =
 proc genCase(p: BProc, t: PNode, d: var TLoc) =
   genLineDir(p, t)
   if not isEmptyType(t.typ) and d.k == locNone:
-    getTemp(p, t.typ, d)
+    d = getTemp(p, t.typ)
   case skipTypes(t[0].typ, abstractVarRange).kind
   of tyString:
     genStringCase(p, t, tyString, d)
@@ -1033,13 +1070,13 @@ proc genTryCpp(p: BProc, t: PNode, d: var TLoc) =
   p.module.includeHeader("<exception>")
 
   if not isEmptyType(t.typ) and d.k == locNone:
-    getTemp(p, t.typ, d)
+    d = getTemp(p, t.typ)
   genLineDir(p, t)
 
   inc(p.labels, 2)
   let etmp = p.labels
-
-  lineCg(p, cpsStmts, "std::exception_ptr T$1_;$n", [etmp])
+  #init on locals, fixes #23306
+  lineCg(p, cpsLocals, "std::exception_ptr T$1_;$n", [etmp])
 
   let fin = if t[^1].kind == nkFinally: t[^1] else: nil
   p.nestedTryStmts.add((fin, false, 0.Natural))
@@ -1198,7 +1235,7 @@ proc genTryCppOld(p: BProc, t: PNode, d: var TLoc) =
     expr(p, body, d)
 
   if not isEmptyType(t.typ) and d.k == locNone:
-    getTemp(p, t.typ, d)
+    d = getTemp(p, t.typ)
   genLineDir(p, t)
   cgsym(p.module, "popCurrentExceptionEx")
   let fin = if t[^1].kind == nkFinally: t[^1] else: nil
@@ -1276,7 +1313,7 @@ proc genTryGoto(p: BProc; t: PNode; d: var TLoc) =
   p.flags.incl nimErrorFlagAccessed
 
   if not isEmptyType(t.typ) and d.k == locNone:
-    getTemp(p, t.typ, d)
+    d = getTemp(p, t.typ)
 
   expr(p, t[0], d)
 
@@ -1383,7 +1420,7 @@ proc genTrySetjmp(p: BProc, t: PNode, d: var TLoc) =
   #    propagateCurrentException();
   #
   if not isEmptyType(t.typ) and d.k == locNone:
-    getTemp(p, t.typ, d)
+    d = getTemp(p, t.typ)
   let quirkyExceptions = p.config.exc == excQuirky or
       (t.kind == nkHiddenTryStmt and sfSystemModule in p.module.module.flags)
   if not quirkyExceptions:
@@ -1392,7 +1429,7 @@ proc genTrySetjmp(p: BProc, t: PNode, d: var TLoc) =
     p.flags.incl noSafePoints
   genLineDir(p, t)
   cgsym(p.module, "Exception")
-  var safePoint: Rope
+  var safePoint: Rope = ""
   if not quirkyExceptions:
     safePoint = getTempName(p.module)
     linefmt(p, cpsLocals, "#TSafePoint $1;$n", [safePoint])
@@ -1457,7 +1494,8 @@ proc genTrySetjmp(p: BProc, t: PNode, d: var TLoc) =
         let memberName = if p.module.compileToCpp: "m_type" else: "Sup.m_type"
         if optTinyRtti in p.config.globalOptions:
           let checkFor = $getObjDepth(t[i][j].typ)
-          appcg(p.module, orExpr, "#isObjDisplayCheck(#nimBorrowCurrentException()->$1, $2, $3)", [memberName, checkFor,  $genDisplayElem(MD5Digest(hashType(t[i][j].typ, p.config)))])
+          appcg(p.module, orExpr, "#isObjDisplayCheck(#nimBorrowCurrentException()->$1, $2, $3)",
+              [memberName, checkFor, $genDisplayElem(MD5Digest(hashType(t[i][j].typ, p.config)))])
         else:
           let checkFor = genTypeInfoV1(p.module, t[i][j].typ, t[i][j].info)
           appcg(p.module, orExpr, "#isObj(#nimBorrowCurrentException()->$1, $2)", [memberName, checkFor])
@@ -1488,28 +1526,31 @@ proc genTrySetjmp(p: BProc, t: PNode, d: var TLoc) =
 
 proc genAsmOrEmitStmt(p: BProc, t: PNode, isAsmStmt=false; result: var Rope) =
   var res = ""
-  for it in t.sons:
+  let offset =
+    if isAsmStmt: 1 # first son is pragmas
+    else: 0
+
+  for i in offset..<t.len:
+    let it = t[i]
     case it.kind
     of nkStrLit..nkTripleStrLit:
       res.add(it.strVal)
     of nkSym:
       var sym = it.sym
       if sym.kind in {skProc, skFunc, skIterator, skMethod}:
-        var a: TLoc
-        initLocExpr(p, it, a)
+        var a: TLoc = initLocExpr(p, it)
         res.add($rdLoc(a))
       elif sym.kind == skType:
         res.add($getTypeDesc(p.module, sym.typ))
       else:
         discard getTypeDesc(p.module, skipTypes(sym.typ, abstractPtrs))
         fillBackendName(p.module, sym)
-        res.add($sym.loc.r)
+        res.add($sym.loc.snippet)
     of nkTypeOfExpr:
       res.add($getTypeDesc(p.module, it.typ))
     else:
       discard getTypeDesc(p.module, skipTypes(it.typ, abstractPtrs))
-      var a: TLoc
-      initLocExpr(p, it, a)
+      var a: TLoc = initLocExpr(p, it)
       res.add($a.rdLoc)
 
   if isAsmStmt and hasGnuAsm in CC[p.config.cCompiler].props:
@@ -1534,6 +1575,21 @@ proc genAsmStmt(p: BProc, t: PNode) =
   assert(t.kind == nkAsmStmt)
   genLineDir(p, t)
   var s = newRopeAppender()
+
+  var asmSyntax = ""
+  if (let p = t[0]; p.kind == nkPragma):
+    for i in p:
+      if whichPragma(i) == wAsmSyntax:
+        asmSyntax = i[1].strVal
+
+  if asmSyntax != "" and
+     not (
+      asmSyntax == "gcc" and hasGnuAsm in CC[p.config.cCompiler].props or
+      asmSyntax == "vcc" and hasGnuAsm notin CC[p.config.cCompiler].props):
+    localError(
+      p.config, t.info,
+      "Your compiler does not support the specified inline assembler")
+
   genAsmOrEmitStmt(p, t, isAsmStmt=true, s)
   # see bug #2362, "top level asm statements" seem to be a mis-feature
   # but even if we don't do this, the example in #2362 cannot possibly
@@ -1571,9 +1627,9 @@ proc genPragma(p: BProc, n: PNode) =
     case whichPragma(it)
     of wEmit: genEmit(p, it)
     of wPush:
-      processPushBackendOption(p.optionsStack, p.options, n, i+1)
+      processPushBackendOption(p.config, p.optionsStack, p.options, n, i+1)
     of wPop:
-      processPopBackendOption(p.optionsStack, p.options)
+      processPopBackendOption(p.config, p.optionsStack, p.options)
     else: discard
 
 
@@ -1611,11 +1667,10 @@ when false:
     expr(p, call, d)
 
 proc asgnFieldDiscriminant(p: BProc, e: PNode) =
-  var a, tmp: TLoc
   var dotExpr = e[0]
   if dotExpr.kind == nkCheckedFieldExpr: dotExpr = dotExpr[0]
-  initLocExpr(p, e[0], a)
-  getTemp(p, a.t, tmp)
+  var a = initLocExpr(p, e[0])
+  var tmp: TLoc = getTemp(p, a.t)
   expr(p, e[1], tmp)
   if p.inUncheckedAssignSection == 0:
     let field = dotExpr[1].sym
@@ -1633,9 +1688,8 @@ proc genAsgn(p: BProc, e: PNode, fastAsgn: bool) =
   else:
     let le = e[0]
     let ri = e[1]
-    var a: TLoc
+    var a: TLoc = initLoc(locNone, le, OnUnknown)
     discard getTypeDesc(p.module, le.typ.skipTypes(skipPtrs), dkVar)
-    initLoc(a, locNone, le, OnUnknown)
     a.flags.incl(lfEnforceDeref)
     a.flags.incl(lfPrepareForMutation)
     genLineDir(p, le) # it can be a nkBracketExpr, which may raise
@@ -1647,7 +1701,7 @@ proc genAsgn(p: BProc, e: PNode, fastAsgn: bool) =
     loadInto(p, le, ri, a)
 
 proc genStmts(p: BProc, t: PNode) =
-  var a: TLoc
+  var a: TLoc = default(TLoc)
 
   let isPush = p.config.hasHint(hintExtendedContext)
   if isPush: pushInfoContext(p.config, t.info)

compiler/ccgthreadvars.nim

@@ -30,7 +30,7 @@ proc declareThreadVar(m: BModule, s: PSym, isExtern: bool) =
     # allocator for it :-(
     if not containsOrIncl(m.g.nimtvDeclared, s.id):
       m.g.nimtvDeps.add(s.loc.t)
-      m.g.nimtv.addf("$1 $2;$n", [getTypeDesc(m, s.loc.t), s.loc.r])
+      m.g.nimtv.addf("$1 $2;$n", [getTypeDesc(m, s.loc.t), s.loc.snippet])
   else:
     if isExtern: m.s[cfsVars].add("extern ")
     elif lfExportLib in s.loc.flags: m.s[cfsVars].add("N_LIB_EXPORT_VAR ")
@@ -41,13 +41,17 @@ proc declareThreadVar(m: BModule, s: PSym, isExtern: bool) =
         m.s[cfsVars].add("NIM_THREAD_LOCAL ")
       else: m.s[cfsVars].add("NIM_THREADVAR ")
     m.s[cfsVars].add(getTypeDesc(m, s.loc.t))
-    m.s[cfsVars].addf(" $1;$n", [s.loc.r])
+    m.s[cfsVars].addf(" $1;$n", [s.loc.snippet])
 
 proc generateThreadLocalStorage(m: BModule) =
   if m.g.nimtv != "" and (usesThreadVars in m.flags or sfMainModule in m.module.flags):
     for t in items(m.g.nimtvDeps): discard getTypeDesc(m, t)
     finishTypeDescriptions(m)
-    m.s[cfsSeqTypes].addf("typedef struct {$1} NimThreadVars;$n", [m.g.nimtv])
+    var typedef = newBuilder("")
+    typedef.addTypedef(name = "NimThreadVars"):
+      typedef.addSimpleStruct(m, name = "", baseType = ""):
+        typedef.add(m.g.nimtv)
+    m.s[cfsSeqTypes].add(typedef)
 
 proc generateThreadVarsSize(m: BModule) =
   if m.g.nimtv != "":

compiler/ccgtrav.nim

@@ -21,7 +21,7 @@ const
 
 proc genTraverseProc(c: TTraversalClosure, accessor: Rope, typ: PType)
 proc genCaseRange(p: BProc, branch: PNode)
-proc getTemp(p: BProc, t: PType, result: var TLoc; needsInit=false)
+proc getTemp(p: BProc, t: PType, needsInit=false): TLoc
 
 proc genTraverseProc(c: TTraversalClosure, accessor: Rope, n: PNode;
                      typ: PType) =
@@ -34,10 +34,10 @@ proc genTraverseProc(c: TTraversalClosure, accessor: Rope, n: PNode;
     if (n[0].kind != nkSym): internalError(c.p.config, n.info, "genTraverseProc")
     var p = c.p
     let disc = n[0].sym
-    if disc.loc.r == "": fillObjectFields(c.p.module, typ)
+    if disc.loc.snippet == "": fillObjectFields(c.p.module, typ)
     if disc.loc.t == nil:
       internalError(c.p.config, n.info, "genTraverseProc()")
-    lineF(p, cpsStmts, "switch ($1.$2) {$n", [accessor, disc.loc.r])
+    lineF(p, cpsStmts, "switch ($1.$2) {$n", [accessor, disc.loc.snippet])
     for i in 1..<n.len:
       let branch = n[i]
       assert branch.kind in {nkOfBranch, nkElse}
@@ -51,10 +51,10 @@ proc genTraverseProc(c: TTraversalClosure, accessor: Rope, n: PNode;
   of nkSym:
     let field = n.sym
     if field.typ.kind == tyVoid: return
-    if field.loc.r == "": fillObjectFields(c.p.module, typ)
+    if field.loc.snippet == "": fillObjectFields(c.p.module, typ)
     if field.loc.t == nil:
       internalError(c.p.config, n.info, "genTraverseProc()")
-    genTraverseProc(c, "$1.$2" % [accessor, field.loc.r], field.loc.t)
+    genTraverseProc(c, "$1.$2" % [accessor, field.loc.snippet], field.loc.t)
   else: internalError(c.p.config, n.info, "genTraverseProc()")
 
 proc parentObj(accessor: Rope; m: BModule): Rope {.inline.} =
@@ -71,38 +71,36 @@ proc genTraverseProc(c: TTraversalClosure, accessor: Rope, typ: PType) =
   case typ.kind
   of tyGenericInst, tyGenericBody, tyTypeDesc, tyAlias, tyDistinct, tyInferred,
      tySink, tyOwned:
-    genTraverseProc(c, accessor, lastSon(typ))
+    genTraverseProc(c, accessor, skipModifier(typ))
   of tyArray:
-    let arraySize = lengthOrd(c.p.config, typ[0])
-    var i: TLoc
-    getTemp(p, getSysType(c.p.module.g.graph, unknownLineInfo, tyInt), i)
+    let arraySize = lengthOrd(c.p.config, typ.indexType)
+    var i: TLoc = getTemp(p, getSysType(c.p.module.g.graph, unknownLineInfo, tyInt))
     var oldCode = p.s(cpsStmts)
     freeze oldCode
     linefmt(p, cpsStmts, "for ($1 = 0; $1 < $2; $1++) {$n",
-            [i.r, arraySize])
+            [i.snippet, arraySize])
     let oldLen = p.s(cpsStmts).len
-    genTraverseProc(c, ropecg(c.p.module, "$1[$2]", [accessor, i.r]), typ[1])
+    genTraverseProc(c, ropecg(c.p.module, "$1[$2]", [accessor, i.snippet]), typ.elementType)
     if p.s(cpsStmts).len == oldLen:
       # do not emit dummy long loops for faster debug builds:
       p.s(cpsStmts) = oldCode
     else:
       lineF(p, cpsStmts, "}$n", [])
   of tyObject:
-    for i in 0..<typ.len:
-      var x = typ[i]
-      if x != nil: x = x.skipTypes(skipPtrs)
-      genTraverseProc(c, accessor.parentObj(c.p.module), x)
+    var x = typ.baseClass
+    if x != nil: x = x.skipTypes(skipPtrs)
+    genTraverseProc(c, accessor.parentObj(c.p.module), x)
     if typ.n != nil: genTraverseProc(c, accessor, typ.n, typ)
   of tyTuple:
     let typ = getUniqueType(typ)
-    for i in 0..<typ.len:
-      genTraverseProc(c, ropecg(c.p.module, "$1.Field$2", [accessor, i]), typ[i])
+    for i, a in typ.ikids:
+      genTraverseProc(c, ropecg(c.p.module, "$1.Field$2", [accessor, i]), a)
   of tyRef:
     lineCg(p, cpsStmts, visitorFrmt, [accessor, c.visitorFrmt])
   of tySequence:
     if optSeqDestructors notin c.p.module.config.globalOptions:
       lineCg(p, cpsStmts, visitorFrmt, [accessor, c.visitorFrmt])
-    elif containsGarbageCollectedRef(typ.lastSon):
+    elif containsGarbageCollectedRef(typ.elementType):
       # destructor based seqs are themselves not traced but their data is, if
       # they contain a GC'ed type:
       lineCg(p, cpsStmts, "#nimGCvisitSeq((void*)$1, $2);$n", [accessor, c.visitorFrmt])
@@ -119,17 +117,15 @@ proc genTraverseProc(c: TTraversalClosure, accessor: Rope, typ: PType) =
 proc genTraverseProcSeq(c: TTraversalClosure, accessor: Rope, typ: PType) =
   var p = c.p
   assert typ.kind == tySequence
-  var i: TLoc
-  getTemp(p, getSysType(c.p.module.g.graph, unknownLineInfo, tyInt), i)
+  var i = getTemp(p, getSysType(c.p.module.g.graph, unknownLineInfo, tyInt))
   var oldCode = p.s(cpsStmts)
   freeze oldCode
-  var a: TLoc
-  a.r = accessor
+  var a = TLoc(snippet: accessor)
 
   lineF(p, cpsStmts, "for ($1 = 0; $1 < $2; $1++) {$n",
-      [i.r, lenExpr(c.p, a)])
+      [i.snippet, lenExpr(c.p, a)])
   let oldLen = p.s(cpsStmts).len
-  genTraverseProc(c, "$1$3[$2]" % [accessor, i.r, dataField(c.p)], typ[0])
+  genTraverseProc(c, "$1$3[$2]" % [accessor, i.snippet, dataField(c.p)], typ.elementType)
   if p.s(cpsStmts).len == oldLen:
     # do not emit dummy long loops for faster debug builds:
     p.s(cpsStmts) = oldCode
@@ -137,7 +133,6 @@ proc genTraverseProcSeq(c: TTraversalClosure, accessor: Rope, typ: PType) =
     lineF(p, cpsStmts, "}$n", [])
 
 proc genTraverseProc(m: BModule, origTyp: PType; sig: SigHash): Rope =
-  var c: TTraversalClosure
   var p = newProc(nil, m)
   result = "Marker_" & getTypeName(m, origTyp, sig)
   let
@@ -150,18 +145,19 @@ proc genTraverseProc(m: BModule, origTyp: PType; sig: SigHash): Rope =
   lineF(p, cpsLocals, "$1 a;$n", [t])
   lineF(p, cpsInit, "a = ($1)p;$n", [t])
 
-  c.p = p
-  c.visitorFrmt = "op" # "#nimGCvisit((void*)$1, op);$n"
+  var c = TTraversalClosure(p: p,
+    visitorFrmt: "op" # "#nimGCvisit((void*)$1, op);$n"
+    )
 
   assert typ.kind != tyTypeDesc
   if typ.kind == tySequence:
     genTraverseProcSeq(c, "a".rope, typ)
   else:
-    if skipTypes(typ[0], typedescInst+{tyOwned}).kind == tyArray:
+    if skipTypes(typ.elementType, typedescInst+{tyOwned}).kind == tyArray:
       # C's arrays are broken beyond repair:
-      genTraverseProc(c, "a".rope, typ[0])
+      genTraverseProc(c, "a".rope, typ.elementType)
     else:
-      genTraverseProc(c, "(*a)".rope, typ[0])
+      genTraverseProc(c, "(*a)".rope, typ.elementType)
 
   let generatedProc = "$1 {$n$2$3$4}\n" %
         [header, p.s(cpsLocals), p.s(cpsInit), p.s(cpsStmts)]
@@ -177,7 +173,6 @@ proc genTraverseProc(m: BModule, origTyp: PType; sig: SigHash): Rope =
 proc genTraverseProcForGlobal(m: BModule, s: PSym; info: TLineInfo): Rope =
   discard genTypeInfoV1(m, s.loc.t, info)
 
-  var c: TTraversalClosure
   var p = newProc(nil, m)
   var sLoc = rdLoc(s.loc)
   result = getTempName(m)
@@ -186,8 +181,10 @@ proc genTraverseProcForGlobal(m: BModule, s: PSym; info: TLineInfo): Rope =
     accessThreadLocalVar(p, s)
     sLoc = "NimTV_->" & sLoc
 
-  c.visitorFrmt = "0" # "#nimGCvisit((void*)$1, 0);$n"
-  c.p = p
+  var c = TTraversalClosure(p: p,
+    visitorFrmt: "0" # "#nimGCvisit((void*)$1, 0);$n"
+  )
+
   let header = "static N_NIMCALL(void, $1)(void)" % [result]
   genTraverseProc(c, sLoc, s.loc.t)
 

compiler/ccgutils.nim

@@ -10,8 +10,8 @@
 # This module declares some helpers for the C code generator.
 
 import
-  ast, types, hashes, strutils, msgs, wordrecg,
-  platform, trees, options, cgendata
+  ast, types, msgs, wordrecg,
+  platform, trees, options, cgendata, mangleutils
 
 import std/[hashes, strutils, formatfloat]
 
@@ -21,13 +21,16 @@ when defined(nimPreviewSlimSystem):
 proc getPragmaStmt*(n: PNode, w: TSpecialWord): PNode =
   case n.kind
   of nkStmtList:
+    result = nil
     for i in 0..<n.len:
       result = getPragmaStmt(n[i], w)
       if result != nil: break
   of nkPragma:
+    result = nil
     for i in 0..<n.len:
       if whichPragma(n[i]) == w: return n[i]
-  else: discard
+  else:
+    result = nil
 
 proc stmtsContainPragma*(n: PNode, w: TSpecialWord): bool =
   result = getPragmaStmt(n, w) != nil
@@ -65,53 +68,6 @@ proc makeSingleLineCString*(s: string): string =
     c.toCChar(result)
   result.add('\"')
 
-proc mangle*(name: string): string =
-  result = newStringOfCap(name.len)
-  var start = 0
-  if name[0] in Digits:
-    result.add("X" & name[0])
-    start = 1
-  var requiresUnderscore = false
-  template special(x) =
-    result.add x
-    requiresUnderscore = true
-  for i in start..<name.len:
-    let c = name[i]
-    case c
-    of 'a'..'z', '0'..'9', 'A'..'Z':
-      result.add(c)
-    of '_':
-      # we generate names like 'foo_9' for scope disambiguations and so
-      # disallow this here:
-      if i > 0 and i < name.len-1 and name[i+1] in Digits:
-        discard
-      else:
-        result.add(c)
-    of '$': special "dollar"
-    of '%': special "percent"
-    of '&': special "amp"
-    of '^': special "roof"
-    of '!': special "emark"
-    of '?': special "qmark"
-    of '*': special "star"
-    of '+': special "plus"
-    of '-': special "minus"
-    of '/': special "slash"
-    of '\\': special "backslash"
-    of '=': special "eq"
-    of '<': special "lt"
-    of '>': special "gt"
-    of '~': special "tilde"
-    of ':': special "colon"
-    of '.': special "dot"
-    of '@': special "at"
-    of '|': special "bar"
-    else:
-      result.add("X" & toHex(ord(c), 2))
-      requiresUnderscore = true
-  if requiresUnderscore:
-    result.add "_"
-
 proc mapSetType(conf: ConfigRef; typ: PType): TCTypeKind =
   case int(getSize(conf, typ))
   of 1: result = ctInt8
@@ -171,8 +127,6 @@ proc encodeSym*(m: BModule; s: PSym; makeUnique: bool = false): string =
     name = makeUnique(m, s, name)
   "N" & encodeName(s.skipGenericOwner.name.s) & encodeName(name) & "E"
 
-proc elementType*(n: PType): PType {.inline.} = n.sons[^1]
-
 proc encodeType*(m: BModule; t: PType): string =
   result = ""
   var kindName = ($t.kind)[2..^1]

compiler/cgen.nim

@@ -10,12 +10,15 @@
 ## This module implements the C code generator.
 
 import
-  ast, astalgo, hashes, trees, platform, magicsys, extccomp, options, intsets,
+  ast, astalgo, trees, platform, magicsys, extccomp, options,
   nversion, nimsets, msgs, bitsets, idents, types,
-  ccgutils, os, ropes, math, wordrecg, treetab, cgmeth,
+  ccgutils, ropes, wordrecg, treetab, cgmeth,
   rodutils, renderer, cgendata, aliases,
-  lowerings, tables, sets, ndi, lineinfos, pathutils, transf,
-  injectdestructors, astmsgs, modulepaths, backendpragmas
+  lowerings, ndi, lineinfos, pathutils, transf,
+  injectdestructors, astmsgs, modulepaths, pushpoppragmas,
+  mangleutils
+
+from expanddefaults import caseObjDefaultBranch
 
 import pipelineutils
 
@@ -25,10 +28,10 @@ when defined(nimPreviewSlimSystem):
 when not defined(leanCompiler):
   import spawn, semparallel
 
-import strutils except `%`, addf # collides with ropes.`%`
+import std/strutils except `%`, addf # collides with ropes.`%`
 
 from ic / ic import ModuleBackendFlag
-import dynlib
+import std/[dynlib, math, tables, sets, os, intsets, hashes]
 
 const
   # we use some ASCII control characters to insert directives that will be converted to real code in a postprocessing pass
@@ -67,12 +70,9 @@ proc findPendingModule(m: BModule, s: PSym): BModule =
     var ms = getModule(s)
     result = m.g.modules[ms.position]
 
-proc initLoc(result: var TLoc, k: TLocKind, lode: PNode, s: TStorageLoc, flags: TLocFlags = {}) =
-  result.k = k
-  result.storage = s
-  result.lode = lode
-  result.r = ""
-  result.flags = flags
+proc initLoc(k: TLocKind, lode: PNode, s: TStorageLoc, flags: TLocFlags = {}): TLoc =
+  result = TLoc(k: k, storage: s, lode: lode,
+                snippet: "", flags: flags)
 
 proc fillLoc(a: var TLoc, k: TLocKind, lode: PNode, r: Rope, s: TStorageLoc) {.inline.} =
   # fills the loc if it is not already initialized
@@ -80,7 +80,7 @@ proc fillLoc(a: var TLoc, k: TLocKind, lode: PNode, r: Rope, s: TStorageLoc) {.i
     a.k = k
     a.lode = lode
     a.storage = s
-    if a.r == "": a.r = r
+    if a.snippet == "": a.snippet = r
 
 proc fillLoc(a: var TLoc, k: TLocKind, lode: PNode, s: TStorageLoc) {.inline.} =
   # fills the loc if it is not already initialized
@@ -97,7 +97,7 @@ proc t(a: TLoc): PType {.inline.} =
 
 proc lodeTyp(t: PType): PNode =
   result = newNode(nkEmpty)
-  result.typ = t
+  result.typ() = t
 
 proc isSimpleConst(typ: PType): bool =
   let t = skipTypes(typ, abstractVar)
@@ -127,7 +127,7 @@ proc getModuleDllPath(m: BModule, module: int): Rope =
 proc getModuleDllPath(m: BModule, s: PSym): Rope =
   result = getModuleDllPath(m.g.modules[s.itemId.module])
 
-import macros
+import std/macros
 
 proc cgFormatValue(result: var string; value: string) =
   result.add value
@@ -301,6 +301,8 @@ proc freshLineInfo(p: BProc; info: TLineInfo): bool =
     p.lastLineInfo.line = info.line
     p.lastLineInfo.fileIndex = info.fileIndex
     result = true
+  else:
+    result = false
 
 proc genCLineDir(r: var Rope, p: BProc, info: TLineInfo; conf: ConfigRef) =
   if optLineDir in conf.options:
@@ -309,6 +311,7 @@ proc genCLineDir(r: var Rope, p: BProc, info: TLineInfo; conf: ConfigRef) =
       genCLineDir(r, info.fileIndex, info.safeLineNm, p, info, lastFileIndex)
 
 proc genLineDir(p: BProc, t: PNode) =
+  if p == p.module.preInitProc: return
   let line = t.info.safeLineNm
 
   if optEmbedOrigSrc in p.config.globalOptions:
@@ -337,15 +340,15 @@ proc getTempName(m: BModule): Rope =
 proc rdLoc(a: TLoc): Rope =
   # 'read' location (deref if indirect)
   if lfIndirect in a.flags:
-    result = "(*" & a.r & ")"
+    result = "(*" & a.snippet & ")"
   else:
-    result = a.r
+    result = a.snippet
 
 proc addRdLoc(a: TLoc; result: var Rope) =
   if lfIndirect in a.flags:
-    result.add "(*" & a.r & ")"
+    result.add "(*" & a.snippet & ")"
   else:
-    result.add a.r
+    result.add a.snippet
 
 proc lenField(p: BProc): Rope {.inline.} =
   result = rope(if p.module.compileToCpp: "len" else: "Sup.len")
@@ -368,6 +371,11 @@ proc dataField(p: BProc): Rope =
   else:
     result = rope"->data"
 
+proc genProcPrototype(m: BModule, sym: PSym)
+
+include cbuilderbase
+include cbuilderexprs
+include cbuilderdecls
 include ccgliterals
 include ccgtypes
 
@@ -380,22 +388,22 @@ template mapTypeChooser(a: TLoc): TSymKind = mapTypeChooser(a.lode)
 
 proc addAddrLoc(conf: ConfigRef; a: TLoc; result: var Rope) =
   if lfIndirect notin a.flags and mapType(conf, a.t, mapTypeChooser(a) == skParam) != ctArray:
-    result.add "(&" & a.r & ")"
+    result.add "(&" & a.snippet & ")"
   else:
-    result.add a.r
+    result.add a.snippet
 
 proc addrLoc(conf: ConfigRef; a: TLoc): Rope =
   if lfIndirect notin a.flags and mapType(conf, a.t, mapTypeChooser(a) == skParam) != ctArray:
-    result = "(&" & a.r & ")"
+    result = "(&" & a.snippet & ")"
   else:
-    result = a.r
+    result = a.snippet
 
 proc byRefLoc(p: BProc; a: TLoc): Rope =
   if lfIndirect notin a.flags and mapType(p.config, a.t, mapTypeChooser(a) == skParam) != ctArray and not
       p.module.compileToCpp:
-    result = "(&" & a.r & ")"
+    result = "(&" & a.snippet & ")"
   else:
-    result = a.r
+    result = a.snippet
 
 proc rdCharLoc(a: TLoc): Rope =
   # read a location that may need a char-cast:
@@ -406,7 +414,9 @@ proc rdCharLoc(a: TLoc): Rope =
 type
   TAssignmentFlag = enum
     needToCopy
+    needToCopySinkParam
     needTempForOpenArray
+    needAssignCall
   TAssignmentFlags = set[TAssignmentFlag]
 
 proc genObjConstr(p: BProc, e: PNode, d: var TLoc)
@@ -438,7 +448,7 @@ proc genObjectInit(p: BProc, section: TCProcSection, t: PType, a: var TLoc,
       linefmt(p, section, "$1.m_type = $2;$n", [r, genTypeInfoV1(p.module, t, a.lode.info)])
   of frEmbedded:
     if optTinyRtti in p.config.globalOptions:
-      var tmp: TLoc
+      var tmp: TLoc = default(TLoc)
       if mode == constructRefObj:
         let objType = t.skipTypes(abstractInst+{tyRef})
         rawConstExpr(p, newNodeIT(nkType, a.lode.info, objType), tmp)
@@ -475,9 +485,12 @@ include ccgreset
 proc resetLoc(p: BProc, loc: var TLoc) =
   let containsGcRef = optSeqDestructors notin p.config.globalOptions and containsGarbageCollectedRef(loc.t)
   let typ = skipTypes(loc.t, abstractVarRange)
-  if isImportedCppType(typ): return
+  if isImportedCppType(typ): 
+    var didGenTemp = false
+    linefmt(p, cpsStmts, "$1 = $2;$n", [rdLoc(loc), genCppInitializer(p.module, p, typ, didGenTemp)])
+    return
   if optSeqDestructors in p.config.globalOptions and typ.kind in {tyString, tySequence}:
-    assert loc.r != ""
+    assert loc.snippet != ""
 
     let atyp = skipTypes(loc.t, abstractInst)
     if atyp.kind in {tyVar, tyLent}:
@@ -486,9 +499,8 @@ proc resetLoc(p: BProc, loc: var TLoc) =
       linefmt(p, cpsStmts, "$1.len = 0; $1.p = NIM_NIL;$n", [rdLoc(loc)])
   elif not isComplexValueType(typ):
     if containsGcRef:
-      var nilLoc: TLoc
-      initLoc(nilLoc, locTemp, loc.lode, OnStack)
-      nilLoc.r = rope("NIM_NIL")
+      var nilLoc: TLoc = initLoc(locTemp, loc.lode, OnStack)
+      nilLoc.snippet = rope("NIM_NIL")
       genRefAssign(p, loc, nilLoc)
     else:
       linefmt(p, cpsStmts, "$1 = 0;$n", [rdLoc(loc)])
@@ -504,9 +516,17 @@ proc resetLoc(p: BProc, loc: var TLoc) =
     else:
       # array passed as argument decayed into pointer, bug #7332
       # so we use getTypeDesc here rather than rdLoc(loc)
-      linefmt(p, cpsStmts, "#nimZeroMem((void*)$1, sizeof($2));$n",
-              [addrLoc(p.config, loc),
-              getTypeDesc(p.module, loc.t, descKindFromSymKind mapTypeChooser(loc))])
+      let tyDesc = getTypeDesc(p.module, loc.t, descKindFromSymKind mapTypeChooser(loc))
+      if p.module.compileToCpp and isOrHasImportedCppType(typ):
+        if lfIndirect in loc.flags:
+          #C++ cant be just zeroed. We need to call the ctors
+          var tmp = getTemp(p, loc.t)
+          linefmt(p, cpsStmts,"#nimCopyMem((void*)$1, (NIM_CONST void*)$2, sizeof($3));$n",
+                  [addrLoc(p.config, loc), addrLoc(p.config, tmp), tyDesc])
+      else:
+        linefmt(p, cpsStmts, "#nimZeroMem((void*)$1, sizeof($2));$n",
+                [addrLoc(p.config, loc), tyDesc])
+
       # XXX: We can be extra clever here and call memset only
       # on the bytes following the m_type field?
       genObjectInit(p, cpsStmts, loc.t, loc, constructObj)
@@ -517,15 +537,14 @@ proc constructLoc(p: BProc, loc: var TLoc, isTemp = false) =
     linefmt(p, cpsStmts, "$1.len = 0; $1.p = NIM_NIL;$n", [rdLoc(loc)])
   elif not isComplexValueType(typ):
     if containsGarbageCollectedRef(loc.t):
-      var nilLoc: TLoc
-      initLoc(nilLoc, locTemp, loc.lode, OnStack)
-      nilLoc.r = rope("NIM_NIL")
+      var nilLoc: TLoc = initLoc(locTemp, loc.lode, OnStack)
+      nilLoc.snippet = rope("NIM_NIL")
       genRefAssign(p, loc, nilLoc)
     else:
       linefmt(p, cpsStmts, "$1 = ($2)0;$n", [rdLoc(loc),
         getTypeDesc(p.module, typ, descKindFromSymKind mapTypeChooser(loc))])
   else:
-    if not isTemp or containsGarbageCollectedRef(loc.t):
+    if (not isTemp or containsGarbageCollectedRef(loc.t)) and not hasNoInit(loc.t):
       # don't use nimZeroMem for temporary values for performance if we can
       # avoid it:
       if not isOrHasImportedCppType(typ):
@@ -545,17 +564,16 @@ proc initLocalVar(p: BProc, v: PSym, immediateAsgn: bool) =
     if not immediateAsgn:
       constructLoc(p, v.loc)
 
-proc getTemp(p: BProc, t: PType, result: var TLoc; needsInit=false) =
+proc getTemp(p: BProc, t: PType, needsInit=false): TLoc =
   inc(p.labels)
-  result.r = "T" & rope(p.labels) & "_"
+  result = TLoc(snippet: "T" & rope(p.labels) & "_", k: locTemp, lode: lodeTyp t,
+                storage: OnStack, flags: {})
   if p.module.compileToCpp and isOrHasImportedCppType(t):
-    linefmt(p, cpsLocals, "$1 $2{};$n", [getTypeDesc(p.module, t, dkVar), result.r])
+    var didGenTemp = false
+    linefmt(p, cpsLocals, "$1 $2$3;$n", [getTypeDesc(p.module, t, dkVar), result.snippet,
+      genCppInitializer(p.module, p, t, didGenTemp)])
   else:
-    linefmt(p, cpsLocals, "$1 $2;$n", [getTypeDesc(p.module, t, dkVar), result.r])
-  result.k = locTemp
-  result.lode = lodeTyp t
-  result.storage = OnStack
-  result.flags = {}
+    linefmt(p, cpsLocals, "$1 $2;$n", [getTypeDesc(p.module, t, dkVar), result.snippet])
   constructLoc(p, result, not needsInit)
   when false:
     # XXX Introduce a compiler switch in order to detect these easily.
@@ -566,25 +584,21 @@ proc getTemp(p: BProc, t: PType, result: var TLoc; needsInit=false) =
         echo "ENORMOUS TEMPORARY! ", p.config $ p.lastLineInfo
       writeStackTrace()
 
-proc getTempCpp(p: BProc, t: PType, result: var TLoc; value: Rope) =
+proc getTempCpp(p: BProc, t: PType, value: Rope): TLoc =
   inc(p.labels)
-  result.r = "T" & rope(p.labels) & "_"
-  linefmt(p, cpsStmts, "$1 $2 = $3;$n", [getTypeDesc(p.module, t, dkVar), result.r, value])
-  result.k = locTemp
-  result.lode = lodeTyp t
-  result.storage = OnStack
-  result.flags = {}
+  result = TLoc(snippet: "T" & rope(p.labels) & "_", k: locTemp, lode: lodeTyp t,
+                storage: OnStack, flags: {})
+  linefmt(p, cpsStmts, "auto $1 = $2;$n", [result.snippet, value])
 
-proc getIntTemp(p: BProc, result: var TLoc) =
+proc getIntTemp(p: BProc): TLoc =
   inc(p.labels)
-  result.r = "T" & rope(p.labels) & "_"
-  linefmt(p, cpsLocals, "NI $1;$n", [result.r])
-  result.k = locTemp
-  result.storage = OnStack
-  result.lode = lodeTyp getSysType(p.module.g.graph, unknownLineInfo, tyInt)
-  result.flags = {}
+  result = TLoc(snippet: "T" & rope(p.labels) & "_", k: locTemp,
+                storage: OnStack, lode: lodeTyp getSysType(p.module.g.graph, unknownLineInfo, tyInt),
+                flags: {})
+  linefmt(p, cpsLocals, "NI $1;$n", [result.snippet])
 
 proc localVarDecl(p: BProc; n: PNode): Rope =
+  result = ""
   let s = n.sym
   if s.loc.k == locNone:
     fillLocalName(p, s)
@@ -603,16 +617,20 @@ proc localVarDecl(p: BProc; n: PNode): Rope =
     if sfVolatile in s.flags: result.add(" volatile")
     if sfNoalias in s.flags: result.add(" NIM_NOALIAS")
     result.add(" ")
-    result.add(s.loc.r)
+    result.add(s.loc.snippet)
   else:
-    result = runtimeFormat(s.cgDeclFrmt, [result, s.loc.r])
+    result = runtimeFormat(s.cgDeclFrmt, [result, s.loc.snippet])
 
 proc assignLocalVar(p: BProc, n: PNode) =
   #assert(s.loc.k == locNone) # not yet assigned
   # this need not be fulfilled for inline procs; they are regenerated
   # for each module that uses them!
   let nl = if optLineDir in p.config.options: "" else: "\n"
-  let decl = localVarDecl(p, n) & (if p.module.compileToCpp and isOrHasImportedCppType(n.typ): "{};" else: ";") & nl
+  var decl = localVarDecl(p, n)
+  if p.module.compileToCpp and isOrHasImportedCppType(n.typ):
+    var didGenTemp = false
+    decl.add genCppInitializer(p.module, p, n.typ, didGenTemp)
+  decl.add ";" & nl
   line(p, cpsLocals, decl)
 
 include ccgthreadvars
@@ -642,22 +660,11 @@ proc genGlobalVarDecl(p: BProc, n: PNode; td, value: Rope; decl: var Rope) =
     if sfNoalias in s.flags: decl.add(" NIM_NOALIAS")
   else:
     if value != "":
-      decl = runtimeFormat(s.cgDeclFrmt & " = $#;$n", [td, s.loc.r, value])
+      decl = runtimeFormat(s.cgDeclFrmt & " = $#;$n", [td, s.loc.snippet, value])
     else:
-      decl = runtimeFormat(s.cgDeclFrmt & ";$n", [td, s.loc.r])
+      decl = runtimeFormat(s.cgDeclFrmt & ";$n", [td, s.loc.snippet])
 
-proc genCppVarForCtor(p: BProc, v: PSym; vn, value: PNode; decl: var Rope)
-
-proc callGlobalVarCppCtor(p: BProc; v: PSym; vn, value: PNode) =
-  let s = vn.sym
-  fillBackendName(p.module, s)
-  fillLoc(s.loc, locGlobalVar, vn, OnHeap)
-  var decl: Rope
-  let td = getTypeDesc(p.module, vn.sym.typ, dkVar)
-  genGlobalVarDecl(p, vn, td, "", decl)
-  decl.add " " & $s.loc.r
-  genCppVarForCtor(p, v, vn, value, decl)
-  p.module.s[cfsVars].add decl
+proc genCppVarForCtor(p: BProc; call: PNode; decl: var Rope; didGenTemp: var bool)
 
 proc assignGlobalVar(p: BProc, n: PNode; value: Rope) =
   let s = n.sym
@@ -671,7 +678,7 @@ proc assignGlobalVar(p: BProc, n: PNode; value: Rope) =
     if q != nil and not containsOrIncl(q.declaredThings, s.id):
       varInDynamicLib(q, s)
     else:
-      s.loc.r = mangleDynLibProc(s)
+      s.loc.snippet = mangleDynLibProc(s)
     if value != "":
       internalError(p.config, n.info, ".dynlib variables cannot have a value")
     return
@@ -702,19 +709,31 @@ proc assignGlobalVar(p: BProc, n: PNode; value: Rope) =
             # [^0]: https://en.cppreference.com/w/cpp/language/aggregate_initialization
             # [^1]: https://cplusplus.github.io/CWG/issues/1518.html
             # [^2]: https://eel.is/c++draft/over.match.ctor
-            decl.addf(" $1;$n", [s.loc.r])
+            decl.addf(" $1;$n", [s.loc.snippet])
           else:
-            decl.addf(" $1 = $2;$n", [s.loc.r, value])
+            decl.addf(" $1 = $2;$n", [s.loc.snippet, value])
         else:
-          decl.addf(" $1;$n", [s.loc.r])
+          decl.addf(" $1;$n", [s.loc.snippet])
 
       p.module.s[cfsVars].add(decl)
   if p.withinLoop > 0 and value == "":
     # fixes tests/run/tzeroarray:
     resetLoc(p, s.loc)
 
+proc callGlobalVarCppCtor(p: BProc; v: PSym; vn, value: PNode; didGenTemp: var bool) =
+  let s = vn.sym
+  fillBackendName(p.module, s)
+  fillLoc(s.loc, locGlobalVar, vn, OnHeap)
+  var decl: Rope = ""
+  let td = getTypeDesc(p.module, vn.sym.typ, dkVar)
+  genGlobalVarDecl(p, vn, td, "", decl)
+  decl.add " " & $s.loc.snippet
+  genCppVarForCtor(p, value, decl, didGenTemp)
+  if didGenTemp:  return # generated in the caller
+  p.module.s[cfsVars].add decl
+
 proc assignParam(p: BProc, s: PSym, retType: PType) =
-  assert(s.loc.r != "")
+  assert(s.loc.snippet != "")
   scopeMangledParam(p, s)
 
 proc fillProcLoc(m: BModule; n: PNode) =
@@ -734,19 +753,20 @@ proc genVarPrototype(m: BModule, n: PNode)
 proc requestConstImpl(p: BProc, sym: PSym)
 proc genStmts(p: BProc, t: PNode)
 proc expr(p: BProc, n: PNode, d: var TLoc)
-proc genProcPrototype(m: BModule, sym: PSym)
+
 proc putLocIntoDest(p: BProc, d: var TLoc, s: TLoc)
 proc intLiteral(i: BiggestInt; result: var Rope)
 proc genLiteral(p: BProc, n: PNode; result: var Rope)
 proc genOtherArg(p: BProc; ri: PNode; i: int; typ: PType; result: var Rope; argsCounter: var int)
 proc raiseExit(p: BProc)
+proc raiseExitCleanup(p: BProc, destroy: string)
 
-proc initLocExpr(p: BProc, e: PNode, result: var TLoc, flags: TLocFlags = {}) =
-  initLoc(result, locNone, e, OnUnknown, flags)
+proc initLocExpr(p: BProc, e: PNode, flags: TLocFlags = {}): TLoc =
+  result = initLoc(locNone, e, OnUnknown, flags)
   expr(p, e, result)
 
-proc initLocExprSingleUse(p: BProc, e: PNode, result: var TLoc) =
-  initLoc(result, locNone, e, OnUnknown)
+proc initLocExprSingleUse(p: BProc, e: PNode): TLoc =
+  result = initLoc(locNone, e, OnUnknown)
   if e.kind in nkCallKinds and (e[0].kind != nkSym or e[0].sym.magic == mNone):
     # We cannot check for tfNoSideEffect here because of mutable parameters.
     discard "bug #8202; enforce evaluation order for nested calls for C++ too"
@@ -766,15 +786,11 @@ $1define nimfr_(proc, file) \
   TFrame FR_; \
   FR_.procname = proc; FR_.filename = file; FR_.line = 0; FR_.len = 0; #nimFrame(&FR_);
 
-  $1define nimfrs_(proc, file, slots, length) \
-    struct {TFrame* prev;NCSTRING procname;NI line;NCSTRING filename;NI len;VarSlot s[slots];} FR_; \
-    FR_.procname = proc; FR_.filename = file; FR_.line = 0; FR_.len = length; #nimFrame((TFrame*)&FR_);
+$1define nimln_(n) \
+  FR_.line = n;
 
-  $1define nimln_(n) \
-    FR_.line = n;
-
-  $1define nimlf_(n, file) \
-    FR_.line = n; FR_.filename = file;
+$1define nimlf_(n, file) \
+  FR_.line = n; FR_.filename = file;
 
 """
   if p.module.s[cfsFrameDefines].len == 0:
@@ -837,9 +853,8 @@ proc loadDynamicLib(m: BModule, lib: PLib) =
       var p = newProc(nil, m)
       p.options.excl optStackTrace
       p.flags.incl nimErrorFlagDisabled
-      var dest: TLoc
-      initLoc(dest, locTemp, lib.path, OnStack)
-      dest.r = getTempName(m)
+      var dest: TLoc = initLoc(locTemp, lib.path, OnStack)
+      dest.snippet = getTempName(m)
       appcg(m, m.s[cfsDynLibInit],"$1 $2;$n",
            [getTypeDesc(m, lib.path.typ, dkVar), rdLoc(dest)])
       expr(p, lib.path, dest)
@@ -857,7 +872,7 @@ proc mangleDynLibProc(sym: PSym): Rope =
   # we have to build this as a single rope in order not to trip the
   # optimization in genInfixCall, see test tests/cpp/t8241.nim
   if sfCompilerProc in sym.flags:
-    # NOTE: sym.loc.r is the external name!
+    # NOTE: sym.loc.snippet is the external name!
     result = rope(sym.name.s)
   else:
     result = rope(strutils.`%`("Dl_$1_", $sym.id))
@@ -865,19 +880,18 @@ proc mangleDynLibProc(sym: PSym): Rope =
 proc symInDynamicLib(m: BModule, sym: PSym) =
   var lib = sym.annex
   let isCall = isGetProcAddr(lib)
-  var extname = sym.loc.r
+  var extname = sym.loc.snippet
   if not isCall: loadDynamicLib(m, lib)
   var tmp = mangleDynLibProc(sym)
-  sym.loc.r = tmp             # from now on we only need the internal name
+  sym.loc.snippet = tmp             # from now on we only need the internal name
   sym.typ.sym = nil           # generate a new name
   inc(m.labels, 2)
   if isCall:
     let n = lib.path
-    var a: TLoc
-    initLocExpr(m.initProc, n[0], a)
+    var a: TLoc = initLocExpr(m.initProc, n[0])
     var params = rdLoc(a) & "("
     for i in 1..<n.len-1:
-      initLocExpr(m.initProc, n[i], a)
+      a = initLocExpr(m.initProc, n[i])
       params.add(rdLoc(a))
       params.add(", ")
     let load = "\t$1 = ($2) ($3$4));$n" %
@@ -896,24 +910,24 @@ proc symInDynamicLib(m: BModule, sym: PSym) =
     appcg(m, m.s[cfsDynLibInit],
         "\t$1 = ($2) #nimGetProcAddr($3, $4);$n",
         [tmp, getTypeDesc(m, sym.typ, dkVar), lib.name, makeCString($extname)])
-  m.s[cfsVars].addf("$2 $1;$n", [sym.loc.r, getTypeDesc(m, sym.loc.t, dkVar)])
+  m.s[cfsVars].addf("$2 $1;$n", [sym.loc.snippet, getTypeDesc(m, sym.loc.t, dkVar)])
 
 proc varInDynamicLib(m: BModule, sym: PSym) =
   var lib = sym.annex
-  var extname = sym.loc.r
+  var extname = sym.loc.snippet
   loadDynamicLib(m, lib)
   incl(sym.loc.flags, lfIndirect)
   var tmp = mangleDynLibProc(sym)
-  sym.loc.r = tmp             # from now on we only need the internal name
+  sym.loc.snippet = tmp             # from now on we only need the internal name
   inc(m.labels, 2)
   appcg(m, m.s[cfsDynLibInit],
       "$1 = ($2*) #nimGetProcAddr($3, $4);$n",
       [tmp, getTypeDesc(m, sym.typ, dkVar), lib.name, makeCString($extname)])
   m.s[cfsVars].addf("$2* $1;$n",
-      [sym.loc.r, getTypeDesc(m, sym.loc.t, dkVar)])
+      [sym.loc.snippet, getTypeDesc(m, sym.loc.t, dkVar)])
 
 proc symInDynamicLibPartial(m: BModule, sym: PSym) =
-  sym.loc.r = mangleDynLibProc(sym)
+  sym.loc.snippet = mangleDynLibProc(sym)
   sym.typ.sym = nil           # generate a new name
 
 proc cgsymImpl(m: BModule; sym: PSym) {.inline.} =
@@ -936,7 +950,7 @@ proc cgsymValue(m: BModule, name: string): Rope =
     cgsymImpl m, sym
   else:
     rawMessage(m.config, errGenerated, "system module needs: " & name)
-  result = sym.loc.r
+  result = sym.loc.snippet
   if m.hcrOn and sym != nil and sym.kind in {skProc..skIterator}:
     result.addActualSuffixForHCR(m.module, sym)
 
@@ -1013,6 +1027,7 @@ proc containsResult(n: PNode): bool =
       if containsResult(n[i]): return true
 
 proc easyResultAsgn(n: PNode): PNode =
+  result = nil
   case n.kind
   of nkStmtList, nkStmtListExpr:
     var i = 0
@@ -1062,7 +1077,11 @@ proc allPathsAsgnResult(p: BProc; n: PNode): InitResultEnum =
       if result != Unknown: return result
   of nkAsgn, nkFastAsgn, nkSinkAsgn:
     if n[0].kind == nkSym and n[0].sym.kind == skResult:
-      if not containsResult(n[1]): result = InitSkippable
+      if not containsResult(n[1]):
+        if allPathsAsgnResult(p, n[1]) == InitRequired:
+          result = InitRequired
+        else:
+          result = InitSkippable
       else: result = InitRequired
     elif containsResult(n):
       result = InitRequired
@@ -1140,6 +1159,10 @@ proc allPathsAsgnResult(p: BProc; n: PNode): InitResultEnum =
         allPathsInBranch(n[i])
   of nkRaiseStmt:
     result = InitRequired
+  of nkChckRangeF, nkChckRange64, nkChckRange:
+    # TODO: more checks might need to be covered like overflow, indexDefect etc.
+    # bug #22852
+    result = InitRequired
   else:
     for i in 0..<n.safeLen:
       allPathsInBranch(n[i])
@@ -1147,7 +1170,7 @@ proc allPathsAsgnResult(p: BProc; n: PNode): InitResultEnum =
 proc getProcTypeCast(m: BModule, prc: PSym): Rope =
   result = getTypeDesc(m, prc.loc.t)
   if prc.typ.callConv == ccClosure:
-    var rettype, params: Rope
+    var rettype, params: Rope = ""
     var check = initIntSet()
     genProcParams(m, prc.typ, rettype, params, check)
     result = "$1(*)$2" % [rettype, params]
@@ -1165,21 +1188,22 @@ proc isNoReturn(m: BModule; s: PSym): bool {.inline.} =
 proc genProcAux*(m: BModule, prc: PSym) =
   var p = newProc(prc, m)
   var header = newRopeAppender()
-  if m.config.backend == backendCpp and {sfVirtual, sfConstructor} * prc.flags != {}:
+  let isCppMember = m.config.backend == backendCpp and sfCppMember * prc.flags != {}
+  if isCppMember:
     genMemberProcHeader(m, prc, header)
   else:
     genProcHeader(m, prc, header)
   var returnStmt: Rope = ""
   assert(prc.ast != nil)
 
-  var procBody = transformBody(m.g.graph, m.idgen, prc, dontUseCache)
+  var procBody = transformBody(m.g.graph, m.idgen, prc, {})
   if sfInjectDestructors in prc.flags:
     procBody = injectDestructorCalls(m.g.graph, m.idgen, prc, procBody)
 
   let tmpInfo = prc.info
   discard freshLineInfo(p, prc.info)
 
-  if sfPure notin prc.flags and prc.typ[0] != nil:
+  if sfPure notin prc.flags and prc.typ.returnType != nil:
     if resultPos >= prc.ast.len:
       internalError(m.config, prc.info, "proc has no result symbol")
     let resNode = prc.ast[resultPos]
@@ -1188,13 +1212,12 @@ proc genProcAux*(m: BModule, prc: PSym) =
       if sfNoInit in prc.flags: incl(res.flags, sfNoInit)
       if sfNoInit in prc.flags and p.module.compileToCpp and (let val = easyResultAsgn(procBody); val != nil):
         var decl = localVarDecl(p, resNode)
-        var a: TLoc
-        initLocExprSingleUse(p, val, a)
+        var a: TLoc = initLocExprSingleUse(p, val)
         linefmt(p, cpsStmts, "$1 = $2;$n", [decl, rdLoc(a)])
       else:
         # declare the result symbol:
         assignLocalVar(p, resNode)
-        assert(res.loc.r != "")
+        assert(res.loc.snippet != "")
         if p.config.selectedGC in {gcArc, gcAtomicArc, gcOrc} and
             allPathsAsgnResult(p, procBody) == InitSkippable:
           # In an ideal world the codegen could rely on injectdestructors doing its job properly
@@ -1204,10 +1227,12 @@ proc genProcAux*(m: BModule, prc: PSym) =
           initLocalVar(p, res, immediateAsgn=false)
       returnStmt = ropecg(p.module, "\treturn $1;$n", [rdLoc(res.loc)])
     elif sfConstructor in prc.flags:
+      resNode.sym.loc.flags.incl lfIndirect
       fillLoc(resNode.sym.loc, locParam, resNode, "this", OnHeap)
+      prc.loc.snippet = getTypeDesc(m, resNode.sym.loc.t, dkVar)
     else:
       fillResult(p.config, resNode, prc.typ)
-      assignParam(p, res, prc.typ[0])
+      assignParam(p, res, prc.typ.returnType)
       # We simplify 'unsureAsgn(result, nil); unsureAsgn(result, x)'
       # to 'unsureAsgn(result, x)'
       # Sketch why this is correct: If 'result' points to a stack location
@@ -1225,19 +1250,19 @@ proc genProcAux*(m: BModule, prc: PSym) =
   for i in 1..<prc.typ.n.len:
     let param = prc.typ.n[i].sym
     if param.typ.isCompileTimeOnly: continue
-    assignParam(p, param, prc.typ[0])
+    assignParam(p, param, prc.typ.returnType)
   closureSetup(p, prc)
   genProcBody(p, procBody)
 
   prc.info = tmpInfo
 
-  var generatedProc: Rope
+  var generatedProc: Rope = ""
   generatedProc.genCLineDir prc.info, m.config
   if isNoReturn(p.module, prc):
-    if hasDeclspec in extccomp.CC[p.config.cCompiler].props:
+    if hasDeclspec in extccomp.CC[p.config.cCompiler].props and not isCppMember:
       header = "__declspec(noreturn) " & header
   if sfPure in prc.flags:
-    if hasDeclspec in extccomp.CC[p.config.cCompiler].props:
+    if hasDeclspec in extccomp.CC[p.config.cCompiler].props and not isCppMember:
       header = "__declspec(naked) " & header
     generatedProc.add ropecg(p.module, "$1 {$n$2$3$4}$N$N",
                          [header, p.s(cpsLocals), p.s(cpsInit), p.s(cpsStmts)])
@@ -1269,7 +1294,7 @@ proc genProcAux*(m: BModule, prc: PSym) =
   m.s[cfsProcs].add(generatedProc)
   if isReloadable(m, prc):
     m.s[cfsDynLibInit].addf("\t$1 = ($3) hcrRegisterProc($4, \"$1\", (void*)$2);$n",
-         [prc.loc.r, prc.loc.r & "_actual", getProcTypeCast(m, prc), getModuleDllPath(m, prc)])
+         [prc.loc.snippet, prc.loc.snippet & "_actual", getProcTypeCast(m, prc), getModuleDllPath(m, prc)])
 
 proc requiresExternC(m: BModule; sym: PSym): bool {.inline.} =
   result = (sfCompileToCpp in m.module.flags and
@@ -1282,7 +1307,7 @@ proc requiresExternC(m: BModule; sym: PSym): bool {.inline.} =
 
 proc genProcPrototype(m: BModule, sym: PSym) =
   useHeader(m, sym)
-  if lfNoDecl in sym.loc.flags or {sfVirtual, sfConstructor} * sym.flags != {}: return
+  if lfNoDecl in sym.loc.flags or sfCppMember * sym.flags != {}: return
   if lfDynamicLib in sym.loc.flags:
     if sym.itemId.module != m.module.position and
         not containsOrIncl(m.declaredThings, sym.id):
@@ -1329,7 +1354,7 @@ proc genProcNoForward(m: BModule, prc: PSym) =
       # the hcr dynlib (also put it in the DynLibInit section - right after it gets loaded)
       if isReloadable(q, prc):
         q.s[cfsDynLibInit].addf("\t$1 = ($2) hcrRegisterProc($3, \"$1\", (void*)$1);$n",
-            [prc.loc.r, getTypeDesc(q, prc.loc.t), getModuleDllPath(m, q.module)])
+            [prc.loc.snippet, getTypeDesc(q, prc.loc.t), getModuleDllPath(m, q.module)])
     else:
       symInDynamicLibPartial(m, prc)
   elif prc.typ.callConv == ccInline:
@@ -1346,8 +1371,8 @@ proc genProcNoForward(m: BModule, prc: PSym) =
       #elif {sfExportc, sfImportc} * prc.flags == {}:
       #  # reset name to restore consistency in case of hashing collisions:
       #  echo "resetting ", prc.id, " by ", m.module.name.s
-      #  prc.loc.r = nil
-      #  prc.loc.r = mangleName(m, prc)
+      #  prc.loc.snippet = nil
+      #  prc.loc.snippet = mangleName(m, prc)
       genProcPrototype(m, prc)
       genProcAux(m, prc)
   elif sfImportc notin prc.flags:
@@ -1359,7 +1384,7 @@ proc genProcNoForward(m: BModule, prc: PSym) =
     if isReloadable(m, prc) and prc.id notin m.declaredProtos and
       q != nil and q.module.id != m.module.id:
       m.s[cfsDynLibInit].addf("\t$1 = ($2) hcrGetProc($3, \"$1\");$n",
-           [prc.loc.r, getProcTypeCast(m, prc), getModuleDllPath(m, prc)])
+           [prc.loc.snippet, getProcTypeCast(m, prc), getModuleDllPath(m, prc)])
     genProcPrototype(m, prc)
     if q != nil and not containsOrIncl(q.declaredThings, prc.id):
       # make sure there is a "prototype" in the external module
@@ -1412,7 +1437,7 @@ proc genVarPrototype(m: BModule, n: PNode) =
     return
   if sym.owner.id != m.module.id:
     # else we already have the symbol generated!
-    assert(sym.loc.r != "")
+    assert(sym.loc.snippet != "")
     incl(m.declaredThings, sym.id)
     if sfThread in sym.flags:
       declareThreadVar(m, sym, true)
@@ -1426,9 +1451,9 @@ proc genVarPrototype(m: BModule, n: PNode) =
       if sfRegister in sym.flags: m.s[cfsVars].add(" register")
       if sfVolatile in sym.flags: m.s[cfsVars].add(" volatile")
       if sfNoalias in sym.flags: m.s[cfsVars].add(" NIM_NOALIAS")
-      m.s[cfsVars].addf(" $1;$n", [sym.loc.r])
+      m.s[cfsVars].addf(" $1;$n", [sym.loc.snippet])
       if m.hcrOn: m.initProc.procSec(cpsLocals).addf(
-        "\t$1 = ($2*)hcrGetGlobal($3, \"$1\");$n", [sym.loc.r,
+        "\t$1 = ($2*)hcrGetGlobal($3, \"$1\");$n", [sym.loc.snippet,
         getTypeDesc(m, sym.loc.t, dkVar), getModuleDllPath(m, sym)])
 
 proc addNimDefines(result: var Rope; conf: ConfigRef) {.inline.} =
@@ -1461,17 +1486,19 @@ proc getFileHeader(conf: ConfigRef; cfile: Cfile): Rope =
 
 proc getSomeNameForModule(conf: ConfigRef, filename: AbsoluteFile): Rope =
   ## Returns a mangled module name.
-  result.add mangleModuleName(conf, filename).mangle
+  result = mangleModuleName(conf, filename).mangle
 
 proc getSomeNameForModule(m: BModule): Rope =
   ## Returns a mangled module name.
   assert m.module.kind == skModule
   assert m.module.owner.kind == skPackage
-  result.add mangleModuleName(m.g.config, m.filename).mangle
+  result = mangleModuleName(m.g.config, m.filename).mangle
 
 proc getSomeInitName(m: BModule, suffix: string): Rope =
   if not m.hcrOn:
     result = getSomeNameForModule(m)
+  else:
+    result = ""
   result.add suffix
 
 proc getInitName(m: BModule): Rope =
@@ -1490,10 +1517,10 @@ proc genMainProc(m: BModule) =
   ## this function is called in cgenWriteModules after all modules are closed,
   ## it means raising dependency on the symbols is too late as it will not propagate
   ## into other modules, only simple rope manipulations are allowed
-
-  var preMainCode: Rope
+  var preMainCode: Rope = ""
   if m.hcrOn:
     proc loadLib(handle: string, name: string): Rope =
+      result = ""
       let prc = magicsys.getCompilerProc(m.g.graph, name)
       assert prc != nil
       let n = newStrNode(nkStrLit, prc.annex.path.strVal)
@@ -1517,7 +1544,7 @@ proc genMainProc(m: BModule) =
   else:
     preMainCode.add("\t$1PreMain();\L" % [rope m.config.nimMainPrefix])
 
-  var posixCmdLine: Rope
+  var posixCmdLine: Rope = ""
   if optNoMain notin m.config.globalOptions:
     posixCmdLine.add "N_LIB_PRIVATE int cmdCount;\L"
     posixCmdLine.add "N_LIB_PRIVATE char** cmdLine;\L"
@@ -1823,11 +1850,11 @@ proc hcrGetProcLoadCode(m: BModule, sym, prefix, handle, getProcFunc: string): R
 
   var extname = prefix & sym
   var tmp = mangleDynLibProc(prc)
-  prc.loc.r = tmp
+  prc.loc.snippet = tmp
   prc.typ.sym = nil
 
   if not containsOrIncl(m.declaredThings, prc.id):
-    m.s[cfsVars].addf("static $2 $1;$n", [prc.loc.r, getTypeDesc(m, prc.loc.t, dkVar)])
+    m.s[cfsVars].addf("static $2 $1;$n", [prc.loc.snippet, getTypeDesc(m, prc.loc.t, dkVar)])
 
   result = "\t$1 = ($2) $3($4, $5);$n" %
       [tmp, getTypeDesc(m, prc.typ, dkVar), getProcFunc.rope, handle.rope, makeCString(prefix & sym)]
@@ -1912,9 +1939,6 @@ proc genInitCode(m: BModule) =
 
     if optStackTrace in m.initProc.options and preventStackTrace notin m.flags:
       prc.add(deinitFrame(m.initProc))
-  elif m.config.exc == excGoto:
-    if getCompilerProc(m.g.graph, "nimTestErrorFlag") != nil:
-      m.appcg(prc, "\t#nimTestErrorFlag();$n", [])
 
   prc.addf("}$N", [])
 
@@ -2054,7 +2078,7 @@ proc rawNewModule(g: BModuleList; module: PSym, filename: AbsoluteFile): BModule
   result.preInitProc = newProc(nil, result)
   result.preInitProc.flags.incl nimErrorFlagDisabled
   result.preInitProc.labels = 100_000 # little hack so that unique temporaries are generated
-  initNodeTable(result.dataCache)
+  result.dataCache = initNodeTable()
   result.typeStack = @[]
   result.typeNodesName = getTempName(result)
   result.nimTypesName = getTempName(result)
@@ -2229,7 +2253,23 @@ proc updateCachedModule(m: BModule) =
   cf.flags = {CfileFlag.Cached}
   addFileToCompile(m.config, cf)
 
-proc finalCodegenActions*(graph: ModuleGraph; m: BModule; n: PNode): PNode =
+proc generateLibraryDestroyGlobals(graph: ModuleGraph; m: BModule; body: PNode; isDynlib: bool): PSym =
+  let procname = getIdent(graph.cache, "NimDestroyGlobals")
+  result = newSym(skProc, procname, m.idgen, m.module.owner, m.module.info)
+  result.typ = newProcType(m.module.info, m.idgen, m.module.owner)
+  result.typ.callConv = ccCDecl
+  incl result.flags, sfExportc
+  result.loc.snippet = "NimDestroyGlobals"
+  if isDynlib:
+    incl(result.loc.flags, lfExportLib)
+
+  let theProc = newNodeI(nkProcDef, m.module.info, bodyPos+1)
+  for i in 0..<theProc.len: theProc[i] = newNodeI(nkEmpty, m.module.info)
+  theProc[namePos] = newSymNode(result)
+  theProc[bodyPos] = body
+  result.ast = theProc
+
+proc finalCodegenActions*(graph: ModuleGraph; m: BModule; n: PNode) =
   ## Also called from IC.
   if sfMainModule in m.module.flags:
     # phase ordering problem here: We need to announce this
@@ -2240,6 +2280,13 @@ proc finalCodegenActions*(graph: ModuleGraph; m: BModule; n: PNode): PNode =
     if {optGenStaticLib, optGenDynLib, optNoMain} * m.config.globalOptions == {}:
       for i in countdown(high(graph.globalDestructors), 0):
         n.add graph.globalDestructors[i]
+    else:
+      var body = newNodeI(nkStmtList, m.module.info)
+      for i in countdown(high(graph.globalDestructors), 0):
+        body.add graph.globalDestructors[i]
+      body.flags.incl nfTransf # should not be further transformed
+      let dtor = generateLibraryDestroyGlobals(graph, m, body, optGenDynLib in m.config.globalOptions)
+      genProcAux(m, dtor)
   if pipelineutils.skipCodegen(m.config, n): return
   if moduleHasChanged(graph, m.module):
     # if the module is cached, we don't regenerate the main proc
@@ -2278,7 +2325,11 @@ proc finalCodegenActions*(graph: ModuleGraph; m: BModule; n: PNode): PNode =
 
       if m.g.forwardedProcs.len == 0:
         incl m.flags, objHasKidsValid
-      result = generateMethodDispatchers(graph, m.idgen)
+      if optMultiMethods in m.g.config.globalOptions or
+          m.g.config.selectedGC notin {gcArc, gcOrc, gcAtomicArc} or
+          vtables notin m.g.config.features:
+        generateIfMethodDispatchers(graph, m.idgen)
+
 
   let mm = m
   m.g.modulesClosed.add mm

compiler/cgendata.nim

@@ -10,8 +10,10 @@
 ## This module contains the data structures for the C code generation phase.
 
 import
-  ast, ropes, options, intsets,
-  tables, ndi, lineinfos, pathutils, modulegraphs, sets
+  ast, ropes, options,
+  ndi, lineinfos, pathutils, modulegraphs
+
+import std/[intsets, tables, sets]
 
 type
   TLabel* = Rope              # for the C generator a label is just a rope
@@ -86,7 +88,7 @@ type
     options*: TOptions        # options that should be used for code
                               # generation; this is the same as prc.options
                               # unless prc == nil
-    optionsStack*: seq[TOptions]
+    optionsStack*: seq[(TOptions, TNoteKinds)]
     module*: BModule          # used to prevent excessive parameter passing
     withinLoop*: int          # > 0 if we are within a loop
     splitDecls*: int          # > 0 if we are in some context for C++ that

compiler/cgmeth.nim

@@ -10,12 +10,15 @@
 ## This module implements code generation for methods.
 
 import
-  intsets, options, ast, msgs, idents, renderer, types, magicsys,
-  sempass2, modulegraphs, lineinfos
+  options, ast, msgs, idents, renderer, types, magicsys,
+  sempass2, modulegraphs, lineinfos, astalgo
+
+import std/intsets
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
 
+import std/[tables]
 
 proc genConv(n: PNode, d: PType, downcast: bool; conf: ConfigRef): PNode =
   var dest = skipTypes(d, abstractPtrs)
@@ -44,13 +47,15 @@ proc getDispatcher*(s: PSym): PSym =
   if dispatcherPos < s.ast.len:
     result = s.ast[dispatcherPos].sym
     doAssert sfDispatcher in result.flags
+  else:
+    result = nil
 
 proc methodCall*(n: PNode; conf: ConfigRef): PNode =
   result = n
   # replace ordinary method by dispatcher method:
   let disp = getDispatcher(result[0].sym)
   if disp != nil:
-    result[0].typ = disp.typ
+    result[0].typ() = disp.typ
     result[0].sym = disp
     # change the arguments to up/downcasts to fit the dispatcher's parameters:
     for i in 1..<result.len:
@@ -62,22 +67,25 @@ type
   MethodResult = enum No, Invalid, Yes
 
 proc sameMethodBucket(a, b: PSym; multiMethods: bool): MethodResult =
+  result = No
   if a.name.id != b.name.id: return
-  if a.typ.len != b.typ.len:
+  if a.typ.signatureLen != b.typ.signatureLen:
     return
 
-  for i in 1..<a.typ.len:
-    var aa = a.typ[i]
-    var bb = b.typ[i]
+  var i = 0
+  for x, y in paramTypePairs(a.typ, b.typ):
+    inc i
+    var aa = x
+    var bb = y
     while true:
       aa = skipTypes(aa, {tyGenericInst, tyAlias})
       bb = skipTypes(bb, {tyGenericInst, tyAlias})
       if aa.kind == bb.kind and aa.kind in {tyVar, tyPtr, tyRef, tyLent, tySink}:
-        aa = aa.lastSon
-        bb = bb.lastSon
+        aa = aa.elementType
+        bb = bb.elementType
       else:
         break
-    if sameType(a.typ[i], b.typ[i]):
+    if sameType(x, y):
       if aa.kind == tyObject and result != Invalid:
         result = Yes
     elif aa.kind == tyObject and bb.kind == tyObject and (i == 1 or multiMethods):
@@ -96,10 +104,10 @@ proc sameMethodBucket(a, b: PSym; multiMethods: bool): MethodResult =
   if result == Yes:
     # check for return type:
     # ignore flags of return types; # bug #22673
-    if not sameTypeOrNil(a.typ[0], b.typ[0], {IgnoreFlags}):
-      if b.typ[0] != nil and b.typ[0].kind == tyUntyped:
+    if not sameTypeOrNil(a.typ.returnType, b.typ.returnType, {IgnoreFlags}):
+      if b.typ.returnType != nil and b.typ.returnType.kind == tyUntyped:
         # infer 'auto' from the base to make it consistent:
-        b.typ[0] = a.typ[0]
+        b.typ.setReturnType a.typ.returnType
       else:
         return No
 
@@ -118,15 +126,15 @@ proc createDispatcher(s: PSym; g: ModuleGraph; idgen: IdGenerator): PSym =
   incl(disp.flags, sfDispatcher)
   excl(disp.flags, sfExported)
   let old = disp.typ
-  disp.typ = copyType(disp.typ, nextTypeId(idgen), disp.typ.owner)
+  disp.typ = copyType(disp.typ, idgen, disp.typ.owner)
   copyTypeProps(g, idgen.module, disp.typ, old)
 
   # we can't inline the dispatcher itself (for now):
   if disp.typ.callConv == ccInline: disp.typ.callConv = ccNimCall
   disp.ast = copyTree(s.ast)
   disp.ast[bodyPos] = newNodeI(nkEmpty, s.info)
-  disp.loc.r = ""
-  if s.typ[0] != nil:
+  disp.loc.snippet = ""
+  if s.typ.returnType != nil:
     if disp.ast.len > resultPos:
       disp.ast[resultPos].sym = copySym(s.ast[resultPos].sym, idgen)
     else:
@@ -150,7 +158,15 @@ proc fixupDispatcher(meth, disp: PSym; conf: ConfigRef) =
     disp.ast[resultPos] = copyTree(meth.ast[resultPos])
 
 proc methodDef*(g: ModuleGraph; idgen: IdGenerator; s: PSym) =
-  var witness: PSym
+  var witness: PSym = nil
+  if s.typ.firstParamType.owner.getModule != s.getModule and vtables in g.config.features and not
+      g.config.isDefined("nimInternalNonVtablesTesting"):
+    localError(g.config, s.info, errGenerated, "method `" & s.name.s &
+          "` can be defined only in the same module with its type (" & s.typ.firstParamType.typeToString() & ")")
+  if sfImportc in s.flags:
+    localError(g.config, s.info, errGenerated, "method `" & s.name.s &
+          "` is not allowed to have 'importc' pragmas")
+
   for i in 0..<g.methods.len:
     let disp = g.methods[i].dispatcher
     case sameMethodBucket(disp, s, multimethods = optMultiMethods in g.config.globalOptions)
@@ -169,6 +185,11 @@ proc methodDef*(g: ModuleGraph; idgen: IdGenerator; s: PSym) =
     of Invalid:
       if witness.isNil: witness = g.methods[i].methods[0]
   # create a new dispatcher:
+  # stores the id and the position
+  if s.typ.firstParamType.skipTypes(skipPtrs).itemId notin g.bucketTable:
+    g.bucketTable[s.typ.firstParamType.skipTypes(skipPtrs).itemId] = 1
+  else:
+    g.bucketTable.inc(s.typ.firstParamType.skipTypes(skipPtrs).itemId)
   g.methods.add((methods: @[s], dispatcher: createDispatcher(s, g, idgen)))
   #echo "adding ", s.info
   if witness != nil:
@@ -177,8 +198,9 @@ proc methodDef*(g: ModuleGraph; idgen: IdGenerator; s: PSym) =
   elif sfBase notin s.flags:
     message(g.config, s.info, warnUseBase)
 
-proc relevantCol(methods: seq[PSym], col: int): bool =
+proc relevantCol*(methods: seq[PSym], col: int): bool =
   # returns true iff the position is relevant
+  result = false
   var t = methods[0].typ[col].skipTypes(skipPtrs)
   if t.kind == tyObject:
     for i in 1..high(methods):
@@ -187,7 +209,8 @@ proc relevantCol(methods: seq[PSym], col: int): bool =
         return true
 
 proc cmpSignatures(a, b: PSym, relevantCols: IntSet): int =
-  for col in 1..<a.typ.len:
+  result = 0
+  for col in FirstParamAt..<a.typ.signatureLen:
     if contains(relevantCols, col):
       var aa = skipTypes(a.typ[col], skipPtrs)
       var bb = skipTypes(b.typ[col], skipPtrs)
@@ -195,7 +218,7 @@ proc cmpSignatures(a, b: PSym, relevantCols: IntSet): int =
       if (d != high(int)) and d != 0:
         return d
 
-proc sortBucket(a: var seq[PSym], relevantCols: IntSet) =
+proc sortBucket*(a: var seq[PSym], relevantCols: IntSet) =
   # we use shellsort here; fast and simple
   var n = a.len
   var h = 1
@@ -214,16 +237,16 @@ proc sortBucket(a: var seq[PSym], relevantCols: IntSet) =
       a[j] = v
     if h == 1: break
 
-proc genDispatcher(g: ModuleGraph; methods: seq[PSym], relevantCols: IntSet; idgen: IdGenerator): PSym =
+proc genIfDispatcher*(g: ModuleGraph; methods: seq[PSym], relevantCols: IntSet; idgen: IdGenerator): PSym =
   var base = methods[0].ast[dispatcherPos].sym
   result = base
-  var paramLen = base.typ.len
+  var paramLen = base.typ.signatureLen
   var nilchecks = newNodeI(nkStmtList, base.info)
   var disp = newNodeI(nkIfStmt, base.info)
   var ands = getSysMagic(g, unknownLineInfo, "and", mAnd)
   var iss = getSysMagic(g, unknownLineInfo, "of", mOf)
   let boolType = getSysType(g, unknownLineInfo, tyBool)
-  for col in 1..<paramLen:
+  for col in FirstParamAt..<paramLen:
     if contains(relevantCols, col):
       let param = base.typ.n[col].sym
       if param.typ.skipTypes(abstractInst).kind in {tyRef, tyPtr}:
@@ -232,7 +255,7 @@ proc genDispatcher(g: ModuleGraph; methods: seq[PSym], relevantCols: IntSet; idg
   for meth in 0..high(methods):
     var curr = methods[meth]      # generate condition:
     var cond: PNode = nil
-    for col in 1..<paramLen:
+    for col in FirstParamAt..<paramLen:
       if contains(relevantCols, col):
         var isn = newNodeIT(nkCall, base.info, boolType)
         isn.add newSymNode(iss)
@@ -247,7 +270,7 @@ proc genDispatcher(g: ModuleGraph; methods: seq[PSym], relevantCols: IntSet; idg
           cond = a
         else:
           cond = isn
-    let retTyp = base.typ[0]
+    let retTyp = base.typ.returnType
     let call = newNodeIT(nkCall, base.info, retTyp)
     call.add newSymNode(curr)
     for col in 1..<paramLen:
@@ -273,14 +296,13 @@ proc genDispatcher(g: ModuleGraph; methods: seq[PSym], relevantCols: IntSet; idg
   nilchecks.flags.incl nfTransf # should not be further transformed
   result.ast[bodyPos] = nilchecks
 
-proc generateMethodDispatchers*(g: ModuleGraph, idgen: IdGenerator): PNode =
-  result = newNode(nkStmtList)
+proc generateIfMethodDispatchers*(g: ModuleGraph, idgen: IdGenerator) =
   for bucket in 0..<g.methods.len:
     var relevantCols = initIntSet()
-    for col in 1..<g.methods[bucket].methods[0].typ.len:
+    for col in FirstParamAt..<g.methods[bucket].methods[0].typ.signatureLen:
       if relevantCol(g.methods[bucket].methods, col): incl(relevantCols, col)
       if optMultiMethods notin g.config.globalOptions:
         # if multi-methods are not enabled, we are interested only in the first field
         break
     sortBucket(g.methods[bucket].methods, relevantCols)
-    result.add newSymNode(genDispatcher(g, g.methods[bucket].methods, relevantCols, idgen))
+    g.addDispatchers genIfDispatcher(g, g.methods[bucket].methods, relevantCols, idgen)

compiler/closureiters.nim

@@ -18,7 +18,8 @@
 #    dec a
 #
 # Should be transformed to:
-#  STATE0:
+#  case :state
+#  of 0:
 #    if a > 0:
 #      echo "hi"
 #      :state = 1 # Next state
@@ -26,19 +27,14 @@
 #    else:
 #      :state = 2 # Next state
 #      break :stateLoop # Proceed to the next state
-#  STATE1:
+#  of 1:
 #    dec a
 #    :state = 0 # Next state
 #    break :stateLoop # Proceed to the next state
-#  STATE2:
+#  of 2:
 #    :state = -1 # End of execution
-
-# The transformation should play well with lambdalifting, however depending
-# on situation, it can be called either before or after lambdalifting
-# transformation. As such we behave slightly differently, when accessing
-# iterator state, or using temp variables. If lambdalifting did not happen,
-# we just create local variables, so that they will be lifted further on.
-# Otherwise, we utilize existing env, created by lambdalifting.
+#  else:
+#    return
 
 # Lambdalifting treats :state variable specially, it should always end up
 # as the first field in env. Currently C codegen depends on this behavior.
@@ -104,12 +100,13 @@
 # Is transformed to (yields are left in place for example simplicity,
 #    in reality the code is subdivided even more, as described above):
 #
-# STATE0: # Try
+# case :state
+# of 0: # Try
 #   yield 0
 #   raise ...
 #   :state = 2 # What would happen should we not raise
 #   break :stateLoop
-# STATE1: # Except
+# of 1: # Except
 #   yield 1
 #   :tmpResult = 3           # Return
 #   :unrollFinally = true # Return
@@ -117,7 +114,7 @@
 #   break :stateLoop
 #   :state = 2 # What would happen should we not return
 #   break :stateLoop
-# STATE2: # Finally
+# of 2: # Finally
 #   yield 2
 #   if :unrollFinally: # This node is created by `newEndFinallyNode`
 #     if :curExc.isNil:
@@ -130,11 +127,15 @@
 #       raise
 #   state = -1 # Goto next state. In this case we just exit
 #   break :stateLoop
+# else:
+#   return
 
 import
   ast, msgs, idents,
   renderer, magicsys, lowerings, lambdalifting, modulegraphs, lineinfos,
-  tables, options
+  options
+
+import std/tables
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
@@ -143,12 +144,11 @@ type
   Ctx = object
     g: ModuleGraph
     fn: PSym
-    stateVarSym: PSym # :state variable. nil if env already introduced by lambdalifting
     tmpResultSym: PSym # Used when we return, but finally has to interfere
     unrollFinallySym: PSym # Indicates that we're unrolling finally states (either exception happened or premature return)
     curExcSym: PSym # Current exception
 
-    states: seq[PNode] # The resulting states. Every state is an nkState node.
+    states: seq[tuple[label: int, body: PNode]] # The resulting states.
     blockLevel: int # Temp used to transform break and continue stmts
     stateLoopLabel: PSym # Label to break on, when jumping between states.
     exitStateIdx: int # index of the last state
@@ -160,17 +160,18 @@ type
     nearestFinally: int # Index of the nearest finally block. For try/except it
                     # is their finally. For finally it is parent finally. Otherwise -1
     idgen: IdGenerator
+    varStates: Table[ItemId, int] # Used to detect if local variable belongs to multiple states
 
 const
   nkSkip = {nkEmpty..nkNilLit, nkTemplateDef, nkTypeSection, nkStaticStmt,
             nkCommentStmt, nkMixinStmt, nkBindStmt} + procDefs
+  emptyStateLabel = -1
+  localNotSeen = -1
+  localRequiresLifting = -2
 
 proc newStateAccess(ctx: var Ctx): PNode =
-  if ctx.stateVarSym.isNil:
-    result = rawIndirectAccess(newSymNode(getEnvParam(ctx.fn)),
-        getStateField(ctx.g, ctx.fn), ctx.fn.info)
-  else:
-    result = newSymNode(ctx.stateVarSym)
+  result = rawIndirectAccess(newSymNode(getEnvParam(ctx.fn)),
+      getStateField(ctx.g, ctx.fn), ctx.fn.info)
 
 proc newStateAssgn(ctx: var Ctx, toValue: PNode): PNode =
   # Creates state assignment:
@@ -185,28 +186,22 @@ proc newStateAssgn(ctx: var Ctx, stateNo: int = -2): PNode =
 proc newEnvVar(ctx: var Ctx, name: string, typ: PType): PSym =
   result = newSym(skVar, getIdent(ctx.g.cache, name), ctx.idgen, ctx.fn, ctx.fn.info)
   result.typ = typ
-  assert(not typ.isNil)
+  result.flags.incl sfNoInit
+  assert(not typ.isNil, "Env var needs a type")
 
-  if not ctx.stateVarSym.isNil:
-    # We haven't gone through labmda lifting yet, so just create a local var,
-    # it will be lifted later
-    if ctx.tempVars.isNil:
-      ctx.tempVars = newNodeI(nkVarSection, ctx.fn.info)
-      addVar(ctx.tempVars, newSymNode(result))
-  else:
-    let envParam = getEnvParam(ctx.fn)
-    # let obj = envParam.typ.lastSon
-    result = addUniqueField(envParam.typ.lastSon, result, ctx.g.cache, ctx.idgen)
+  let envParam = getEnvParam(ctx.fn)
+  # let obj = envParam.typ.lastSon
+  result = addUniqueField(envParam.typ.elementType, result, ctx.g.cache, ctx.idgen)
 
 proc newEnvVarAccess(ctx: Ctx, s: PSym): PNode =
-  if ctx.stateVarSym.isNil:
-    result = rawIndirectAccess(newSymNode(getEnvParam(ctx.fn)), s, ctx.fn.info)
-  else:
-    result = newSymNode(s)
+  result = rawIndirectAccess(newSymNode(getEnvParam(ctx.fn)), s, ctx.fn.info)
+
+proc newTempVarAccess(ctx: Ctx, s: PSym): PNode =
+  result = newSymNode(s, ctx.fn.info)
 
 proc newTmpResultAccess(ctx: var Ctx): PNode =
   if ctx.tmpResultSym.isNil:
-    ctx.tmpResultSym = ctx.newEnvVar(":tmpResult", ctx.fn.typ[0])
+    ctx.tmpResultSym = ctx.newEnvVar(":tmpResult", ctx.fn.typ.returnType)
   ctx.newEnvVarAccess(ctx.tmpResultSym)
 
 proc newUnrollFinallyAccess(ctx: var Ctx, info: TLineInfo): PNode =
@@ -226,10 +221,7 @@ proc newState(ctx: var Ctx, n, gotoOut: PNode): int =
 
   result = ctx.states.len
   let resLit = ctx.g.newIntLit(n.info, result)
-  let s = newNodeI(nkState, n.info)
-  s.add(resLit)
-  s.add(n)
-  ctx.states.add(s)
+  ctx.states.add((result, n))
   ctx.exceptionTable.add(ctx.curExcHandlingState)
 
   if not gotoOut.isNil:
@@ -248,9 +240,18 @@ proc addGotoOut(n: PNode, gotoOut: PNode): PNode =
   if result.len == 0 or result[^1].kind != nkGotoState:
     result.add(gotoOut)
 
-proc newTempVar(ctx: var Ctx, typ: PType): PSym =
-  result = ctx.newEnvVar(":tmpSlLower" & $ctx.tempVarId, typ)
+proc newTempVarDef(ctx: Ctx, s: PSym, initialValue: PNode): PNode =
+  var v = initialValue
+  if v == nil:
+    v = ctx.g.emptyNode
+  newTree(nkVarSection, newTree(nkIdentDefs, newSymNode(s), ctx.g.emptyNode, v))
+
+proc newTempVar(ctx: var Ctx, typ: PType, parent: PNode, initialValue: PNode = nil): PSym =
+  result = newSym(skVar, getIdent(ctx.g.cache, ":tmpSlLower" & $ctx.tempVarId), ctx.idgen, ctx.fn, ctx.fn.info)
   inc ctx.tempVarId
+  result.typ = typ
+  assert(not typ.isNil, "Temp var needs a type")
+  parent.add(ctx.newTempVarDef(result, initialValue))
 
 proc hasYields(n: PNode): bool =
   # TODO: This is very inefficient. It traverses the node, looking for nkYieldStmt.
@@ -258,10 +259,11 @@ proc hasYields(n: PNode): bool =
   of nkYieldStmt:
     result = true
   of nkSkip:
-    discard
+    result = false
   else:
-    for c in n:
-      if c.hasYields:
+    result = false
+    for i in ord(n.kind == nkCast)..<n.len:
+      if n[i].hasYields:
         result = true
         break
 
@@ -309,12 +311,12 @@ proc newNullifyCurExc(ctx: var Ctx, info: TLineInfo): PNode =
   let curExc = ctx.newCurExcAccess()
   curExc.info = info
   let nilnode = newNode(nkNilLit)
-  nilnode.typ = curExc.typ
+  nilnode.typ() = curExc.typ
   result = newTree(nkAsgn, curExc, nilnode)
 
 proc newOr(g: ModuleGraph, a, b: PNode): PNode {.inline.} =
   result = newTree(nkCall, newSymNode(g.getSysMagic(a.info, "or", mOr)), a, b)
-  result.typ = g.getSysType(a.info, tyBool)
+  result.typ() = g.getSysType(a.info, tyBool)
   result.info = a.info
 
 proc collectExceptState(ctx: var Ctx, n: PNode): PNode {.inline.} =
@@ -325,14 +327,14 @@ proc collectExceptState(ctx: var Ctx, n: PNode): PNode {.inline.} =
       var ifBranch: PNode
 
       if c.len > 1:
-        var cond: PNode
+        var cond: PNode = nil
         for i in 0..<c.len - 1:
           assert(c[i].kind == nkType)
           let nextCond = newTree(nkCall,
             newSymNode(g.getSysMagic(c.info, "of", mOf)),
             g.callCodegenProc("getCurrentException"),
             c[i])
-          nextCond.typ = ctx.g.getSysType(c.info, tyBool)
+          nextCond.typ() = ctx.g.getSysType(c.info, tyBool)
           nextCond.info = c.info
 
           if cond.isNil:
@@ -388,26 +390,29 @@ proc getFinallyNode(ctx: var Ctx, n: PNode): PNode =
 proc hasYieldsInExpressions(n: PNode): bool =
   case n.kind
   of nkSkip:
-    discard
+    result = false
   of nkStmtListExpr:
     if isEmptyType(n.typ):
+      result = false
       for c in n:
         if c.hasYieldsInExpressions:
           return true
     else:
       result = n.hasYields
   of nkCast:
+    result = false
     for i in 1..<n.len:
       if n[i].hasYieldsInExpressions:
         return true
   else:
+    result = false
     for c in n:
       if c.hasYieldsInExpressions:
         return true
 
 proc exprToStmtList(n: PNode): tuple[s, res: PNode] =
   assert(n.kind == nkStmtListExpr)
-  result.s = newNodeI(nkStmtList, n.info)
+  result = (newNodeI(nkStmtList, n.info), nil)
   result.s.sons = @[]
 
   var n = n
@@ -418,21 +423,20 @@ proc exprToStmtList(n: PNode): tuple[s, res: PNode] =
 
   result.res = n
 
-
-proc newEnvVarAsgn(ctx: Ctx, s: PSym, v: PNode): PNode =
+proc newTempVarAsgn(ctx: Ctx, s: PSym, v: PNode): PNode =
   if isEmptyType(v.typ):
     result = v
   else:
-    result = newTree(nkFastAsgn, ctx.newEnvVarAccess(s), v)
+    result = newTree(nkFastAsgn, ctx.newTempVarAccess(s), v)
     result.info = v.info
 
 proc addExprAssgn(ctx: Ctx, output, input: PNode, sym: PSym) =
   if input.kind == nkStmtListExpr:
     let (st, res) = exprToStmtList(input)
     output.add(st)
-    output.add(ctx.newEnvVarAsgn(sym, res))
+    output.add(ctx.newTempVarAsgn(sym, res))
   else:
-    output.add(ctx.newEnvVarAsgn(sym, input))
+    output.add(ctx.newTempVarAsgn(sym, input))
 
 proc convertExprBodyToAsgn(ctx: Ctx, exprBody: PNode, res: PSym): PNode =
   result = newNodeI(nkStmtList, exprBody.info)
@@ -440,7 +444,17 @@ proc convertExprBodyToAsgn(ctx: Ctx, exprBody: PNode, res: PSym): PNode =
 
 proc newNotCall(g: ModuleGraph; e: PNode): PNode =
   result = newTree(nkCall, newSymNode(g.getSysMagic(e.info, "not", mNot), e.info), e)
-  result.typ = g.getSysType(e.info, tyBool)
+  result.typ() = g.getSysType(e.info, tyBool)
+
+proc boolLit(g: ModuleGraph; info: TLineInfo; value: bool): PNode =
+  result = newIntLit(g, info, ord value)
+  result.typ() = getSysType(g, info, tyBool)
+
+proc captureVar(c: var Ctx, s: PSym) =
+  if c.varStates.getOrDefault(s.itemId) != localRequiresLifting:
+    c.varStates[s.itemId] = localRequiresLifting # Mark this variable for lifting
+    let e = getEnvParam(c.fn)
+    discard addField(e.typ.elementType, s, c.g.cache, c.idgen)
 
 proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
   result = n
@@ -472,7 +486,7 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
 
       result = newNodeI(nkStmtListExpr, n.info)
       if n.typ.isNil: internalError(ctx.g.config, "lowerStmtListExprs: constr typ.isNil")
-      result.typ = n.typ
+      result.typ() = n.typ
 
       for i in 0..<n.len:
         case n[i].kind
@@ -495,12 +509,12 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
 
     if ns:
       needsSplit = true
-      var tmp: PSym
+      var tmp: PSym = nil
       let isExpr = not isEmptyType(n.typ)
       if isExpr:
-        tmp = ctx.newTempVar(n.typ)
         result = newNodeI(nkStmtListExpr, n.info)
-        result.typ = n.typ
+        result.typ() = n.typ
+        tmp = ctx.newTempVar(n.typ, result)
       else:
         result = newNodeI(nkStmtList, n.info)
 
@@ -551,7 +565,7 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
         else:
           internalError(ctx.g.config, "lowerStmtListExpr(nkIf): " & $branch.kind)
 
-      if isExpr: result.add(ctx.newEnvVarAccess(tmp))
+      if isExpr: result.add(ctx.newTempVarAccess(tmp))
 
   of nkTryStmt, nkHiddenTryStmt:
     var ns = false
@@ -564,8 +578,8 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
 
       if isExpr:
         result = newNodeI(nkStmtListExpr, n.info)
-        result.typ = n.typ
-        let tmp = ctx.newTempVar(n.typ)
+        result.typ() = n.typ
+        let tmp = ctx.newTempVar(n.typ, result)
 
         n[0] = ctx.convertExprBodyToAsgn(n[0], tmp)
         for i in 1..<n.len:
@@ -581,7 +595,7 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
           else:
             internalError(ctx.g.config, "lowerStmtListExpr(nkTryStmt): " & $branch.kind)
         result.add(n)
-        result.add(ctx.newEnvVarAccess(tmp))
+        result.add(ctx.newTempVarAccess(tmp))
 
   of nkCaseStmt:
     var ns = false
@@ -594,9 +608,9 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
       let isExpr = not isEmptyType(n.typ)
 
       if isExpr:
-        let tmp = ctx.newTempVar(n.typ)
         result = newNodeI(nkStmtListExpr, n.info)
-        result.typ = n.typ
+        result.typ() = n.typ
+        let tmp = ctx.newTempVar(n.typ, result)
 
         if n[0].kind == nkStmtListExpr:
           let (st, ex) = exprToStmtList(n[0])
@@ -613,7 +627,7 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
           else:
             internalError(ctx.g.config, "lowerStmtListExpr(nkCaseStmt): " & $branch.kind)
         result.add(n)
-        result.add(ctx.newEnvVarAccess(tmp))
+        result.add(ctx.newTempVarAccess(tmp))
       elif n[0].kind == nkStmtListExpr:
         result = newNodeI(nkStmtList, n.info)
         let (st, ex) = exprToStmtList(n[0])
@@ -632,7 +646,7 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
 
       if isExpr:
         result = newNodeI(nkStmtListExpr, n.info)
-        result.typ = n.typ
+        result.typ() = n.typ
       else:
         result = newNodeI(nkStmtList, n.info)
 
@@ -643,10 +657,10 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
           result.add(st)
           cond = ex
 
-        let tmp = ctx.newTempVar(cond.typ)
-        result.add(ctx.newEnvVarAsgn(tmp, cond))
+        let tmp = ctx.newTempVar(cond.typ, result, cond)
+        # result.add(ctx.newTempVarAsgn(tmp, cond))
 
-        var check = ctx.newEnvVarAccess(tmp)
+        var check = ctx.newTempVarAccess(tmp)
         if n[0].sym.magic == mOr:
           check = ctx.g.newNotCall(check)
 
@@ -656,12 +670,12 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
           let (st, ex) = exprToStmtList(cond)
           ifBody.add(st)
           cond = ex
-        ifBody.add(ctx.newEnvVarAsgn(tmp, cond))
+        ifBody.add(ctx.newTempVarAsgn(tmp, cond))
 
         let ifBranch = newTree(nkElifBranch, check, ifBody)
         let ifNode = newTree(nkIfStmt, ifBranch)
         result.add(ifNode)
-        result.add(ctx.newEnvVarAccess(tmp))
+        result.add(ctx.newTempVarAccess(tmp))
       else:
         for i in 0..<n.len:
           if n[i].kind == nkStmtListExpr:
@@ -670,9 +684,9 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
             n[i] = ex
 
           if n[i].kind in nkCallKinds: # XXX: This should better be some sort of side effect tracking
-            let tmp = ctx.newTempVar(n[i].typ)
-            result.add(ctx.newEnvVarAsgn(tmp, n[i]))
-            n[i] = ctx.newEnvVarAccess(tmp)
+            let tmp = ctx.newTempVar(n[i].typ, result, n[i])
+            # result.add(ctx.newTempVarAsgn(tmp, n[i]))
+            n[i] = ctx.newTempVarAccess(tmp)
 
         result.add(n)
 
@@ -688,6 +702,12 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
         let (st, ex) = exprToStmtList(c[^1])
         result.add(st)
         c[^1] = ex
+      for i in 0 .. c.len - 3:
+        if c[i].kind == nkSym:
+          let s = c[i].sym
+          if sfForceLift in s.flags:
+            ctx.captureVar(s)
+
       result.add(varSect)
 
   of nkDiscardStmt, nkReturnStmt, nkRaiseStmt:
@@ -712,7 +732,7 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
     if ns:
       needsSplit = true
       result = newNodeI(nkStmtListExpr, n.info)
-      result.typ = n.typ
+      result.typ() = n.typ
       let (st, ex) = exprToStmtList(n[^1])
       result.add(st)
       n[^1] = ex
@@ -773,7 +793,7 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
         let check = newTree(nkIfStmt, branch)
         let newBody = newTree(nkStmtList, st, check, n[1])
 
-        n[0] = newSymNode(ctx.g.getSysSym(n[0].info, "true"))
+        n[0] = ctx.g.boolLit(n[0].info, true)
         n[1] = newBody
 
   of nkDotExpr, nkCheckedFieldExpr:
@@ -782,7 +802,7 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
     if ns:
       needsSplit = true
       result = newNodeI(nkStmtListExpr, n.info)
-      result.typ = n.typ
+      result.typ() = n.typ
       let (st, ex) = exprToStmtList(n[0])
       result.add(st)
       n[0] = ex
@@ -794,10 +814,10 @@ proc lowerStmtListExprs(ctx: var Ctx, n: PNode, needsSplit: var bool): PNode =
     if ns:
       needsSplit = true
       result = newNodeI(nkStmtListExpr, n.info)
-      result.typ = n.typ
+      result.typ() = n.typ
       let (st, ex) = exprToStmtList(n[1])
       n.transitionSonsKind(nkBlockStmt)
-      n.typ = nil
+      n.typ() = nil
       n[1] = st
       result.add(n)
       result.add(ex)
@@ -818,14 +838,14 @@ proc newEndFinallyNode(ctx: var Ctx, info: TLineInfo): PNode =
   #         raise
   let curExc = ctx.newCurExcAccess()
   let nilnode = newNode(nkNilLit)
-  nilnode.typ = curExc.typ
+  nilnode.typ() = curExc.typ
   let cmp = newTree(nkCall, newSymNode(ctx.g.getSysMagic(info, "==", mEqRef), info), curExc, nilnode)
-  cmp.typ = ctx.g.getSysType(info, tyBool)
+  cmp.typ() = ctx.g.getSysType(info, tyBool)
 
   let retStmt =
     if ctx.nearestFinally == 0:
       # last finally, we can return
-      let retValue = if ctx.fn.typ[0].isNil:
+      let retValue = if ctx.fn.typ.returnType.isNil:
                    ctx.g.emptyNode
                  else:
                    newTree(nkFastAsgn,
@@ -1127,10 +1147,10 @@ proc skipEmptyStates(ctx: Ctx, stateIdx: int): int =
     let label = stateIdx
     if label == ctx.exitStateIdx: break
     var newLabel = label
-    if label == -1:
+    if label == emptyStateLabel:
       newLabel = ctx.exitStateIdx
     else:
-      let fs = skipStmtList(ctx, ctx.states[label][1])
+      let fs = skipStmtList(ctx, ctx.states[label].body)
       if fs.kind == nkGotoState:
         newLabel = fs[0].intVal.int
     if label == newLabel: break
@@ -1139,7 +1159,7 @@ proc skipEmptyStates(ctx: Ctx, stateIdx: int): int =
     if maxJumps == 0:
       assert(false, "Internal error")
 
-  result = ctx.states[stateIdx][0].intVal.int
+  result = ctx.states[stateIdx].label
 
 proc skipThroughEmptyStates(ctx: var Ctx, n: PNode): PNode=
   result = n
@@ -1154,9 +1174,9 @@ proc skipThroughEmptyStates(ctx: var Ctx, n: PNode): PNode=
       n[i] = ctx.skipThroughEmptyStates(n[i])
 
 proc newArrayType(g: ModuleGraph; n: int, t: PType; idgen: IdGenerator; owner: PSym): PType =
-  result = newType(tyArray, nextTypeId(idgen), owner)
+  result = newType(tyArray, idgen, owner)
 
-  let rng = newType(tyRange, nextTypeId(idgen), owner)
+  let rng = newType(tyRange, idgen, owner)
   rng.n = newTree(nkRange, g.newIntLit(owner.info, 0), g.newIntLit(owner.info, n - 1))
   rng.rawAddSon(t)
 
@@ -1165,11 +1185,11 @@ proc newArrayType(g: ModuleGraph; n: int, t: PType; idgen: IdGenerator; owner: P
 
 proc createExceptionTable(ctx: var Ctx): PNode {.inline.} =
   result = newNodeI(nkBracket, ctx.fn.info)
-  result.typ = ctx.g.newArrayType(ctx.exceptionTable.len, ctx.g.getSysType(ctx.fn.info, tyInt16), ctx.idgen, ctx.fn)
+  result.typ() = ctx.g.newArrayType(ctx.exceptionTable.len, ctx.g.getSysType(ctx.fn.info, tyInt16), ctx.idgen, ctx.fn)
 
   for i in ctx.exceptionTable:
     let elem = newIntNode(nkIntLit, i)
-    elem.typ = ctx.g.getSysType(ctx.fn.info, tyInt16)
+    elem.typ() = ctx.g.getSysType(ctx.fn.info, tyInt16)
     result.add(elem)
 
 proc newCatchBody(ctx: var Ctx, info: TLineInfo): PNode {.inline.} =
@@ -1192,7 +1212,7 @@ proc newCatchBody(ctx: var Ctx, info: TLineInfo): PNode {.inline.} =
     let getNextState = newTree(nkBracketExpr,
       ctx.createExceptionTable(),
       ctx.newStateAccess())
-    getNextState.typ = intTyp
+    getNextState.typ() = intTyp
 
     # :state = exceptionTable[:state]
     result.add(ctx.newStateAssgn(getNextState))
@@ -1203,7 +1223,7 @@ proc newCatchBody(ctx: var Ctx, info: TLineInfo): PNode {.inline.} =
       ctx.g.getSysMagic(info, "==", mEqI).newSymNode(),
       ctx.newStateAccess(),
       newIntTypeNode(0, intTyp))
-    cond.typ = boolTyp
+    cond.typ() = boolTyp
 
     let raiseStmt = newTree(nkRaiseStmt, ctx.g.emptyNode)
     let ifBranch = newTree(nkElifBranch, cond, raiseStmt)
@@ -1216,7 +1236,7 @@ proc newCatchBody(ctx: var Ctx, info: TLineInfo): PNode {.inline.} =
       ctx.g.getSysMagic(info, "<", mLtI).newSymNode,
       newIntTypeNode(0, intTyp),
       ctx.newStateAccess())
-    cond.typ = boolTyp
+    cond.typ() = boolTyp
 
     let asgn = newTree(nkAsgn, ctx.newUnrollFinallyAccess(info), cond)
     result.add(asgn)
@@ -1227,12 +1247,12 @@ proc newCatchBody(ctx: var Ctx, info: TLineInfo): PNode {.inline.} =
       ctx.g.getSysMagic(info, "<", mLtI).newSymNode,
       ctx.newStateAccess(),
       newIntTypeNode(0, intTyp))
-    cond.typ = boolTyp
+    cond.typ() = boolTyp
 
     let negateState = newTree(nkCall,
       ctx.g.getSysMagic(info, "-", mUnaryMinusI).newSymNode,
       ctx.newStateAccess())
-    negateState.typ = intTyp
+    negateState.typ() = intTyp
 
     let ifBranch = newTree(nkElifBranch, cond, ctx.newStateAssgn(negateState))
     let ifStmt = newTree(nkIfStmt, ifBranch)
@@ -1257,30 +1277,18 @@ proc wrapIntoTryExcept(ctx: var Ctx, n: PNode): PNode {.inline.} =
 proc wrapIntoStateLoop(ctx: var Ctx, n: PNode): PNode =
   # while true:
   #   block :stateLoop:
-  #     gotoState :state
   #     local vars decl (if needed)
   #     body # Might get wrapped in try-except
   let loopBody = newNodeI(nkStmtList, n.info)
-  result = newTree(nkWhileStmt, newSymNode(ctx.g.getSysSym(n.info, "true")), loopBody)
+  result = newTree(nkWhileStmt, ctx.g.boolLit(n.info, true), loopBody)
   result.info = n.info
 
   let localVars = newNodeI(nkStmtList, n.info)
-  if not ctx.stateVarSym.isNil:
-    let varSect = newNodeI(nkVarSection, n.info)
-    addVar(varSect, newSymNode(ctx.stateVarSym))
-    localVars.add(varSect)
-
-    if not ctx.tempVars.isNil:
-      localVars.add(ctx.tempVars)
 
   let blockStmt = newNodeI(nkBlockStmt, n.info)
   blockStmt.add(newSymNode(ctx.stateLoopLabel))
 
-  let gs = newNodeI(nkGotoState, n.info)
-  gs.add(ctx.newStateAccess())
-  gs.add(ctx.g.newIntLit(n.info, ctx.states.len - 1))
-
-  var blockBody = newTree(nkStmtList, gs, localVars, n)
+  var blockBody = newTree(nkStmtList, localVars, n)
   if ctx.hasExceptions:
     blockBody = ctx.wrapIntoTryExcept(blockBody)
 
@@ -1293,29 +1301,28 @@ proc deleteEmptyStates(ctx: var Ctx) =
 
   # Apply new state indexes and mark unused states with -1
   var iValid = 0
-  for i, s in ctx.states:
-    let body = skipStmtList(ctx, s[1])
+  for i, s in ctx.states.mpairs:
+    let body = skipStmtList(ctx, s.body)
     if body.kind == nkGotoState and i != ctx.states.len - 1 and i != 0:
       # This is an empty state. Mark with -1.
-      s[0].intVal = -1
+      s.label = emptyStateLabel
     else:
-      s[0].intVal = iValid
+      s.label = iValid
       inc iValid
 
   for i, s in ctx.states:
-    let body = skipStmtList(ctx, s[1])
+    let body = skipStmtList(ctx, s.body)
     if body.kind != nkGotoState or i == 0:
-      discard ctx.skipThroughEmptyStates(s)
+      discard ctx.skipThroughEmptyStates(s.body)
       let excHandlState = ctx.exceptionTable[i]
       if excHandlState < 0:
         ctx.exceptionTable[i] = -ctx.skipEmptyStates(-excHandlState)
       elif excHandlState != 0:
         ctx.exceptionTable[i] = ctx.skipEmptyStates(excHandlState)
 
-  var i = 0
+  var i = 1 # ignore the entry and the exit
   while i < ctx.states.len - 1:
-    let fs = skipStmtList(ctx, ctx.states[i][1])
-    if fs.kind == nkGotoState and i != 0:
+    if ctx.states[i].label == emptyStateLabel:
       ctx.states.delete(i)
       ctx.exceptionTable.delete(i)
     else:
@@ -1361,6 +1368,7 @@ proc freshVars(n: PNode; c: var FreshVarsContext): PNode =
       else:
         result.add it
   of nkRaiseStmt:
+    result = nil
     localError(c.config, c.info, "unsupported control flow: 'finally: ... raise' duplicated because of 'break'")
   else:
     result = n
@@ -1423,18 +1431,67 @@ proc preprocess(c: var PreprocessContext; n: PNode): PNode =
     for i in 0 ..< n.len:
       result[i] = preprocess(c, n[i])
 
-proc transformClosureIterator*(g: ModuleGraph; idgen: IdGenerator; fn: PSym, n: PNode): PNode =
-  var ctx: Ctx
-  ctx.g = g
-  ctx.fn = fn
-  ctx.idgen = idgen
+proc detectCapturedVars(c: var Ctx, n: PNode, stateIdx: int) =
+  case n.kind
+  of nkSym:
+    let s = n.sym
+    if s.kind in {skResult, skVar, skLet, skForVar, skTemp} and sfGlobal notin s.flags and s.owner == c.fn:
+      let vs = c.varStates.getOrDefault(s.itemId, localNotSeen)
+      if vs == localNotSeen: # First seing this variable
+        c.varStates[s.itemId] = stateIdx
+      elif vs == localRequiresLifting:
+        discard # Sym already marked
+      elif vs != stateIdx:
+        c.captureVar(s)
+  of nkReturnStmt:
+    if n[0].kind in {nkAsgn, nkFastAsgn, nkSinkAsgn}:
+      # we have a `result = result` expression produced by the closure
+      # transform, let's not touch the LHS in order to make the lifting pass
+      # correct when `result` is lifted
+      detectCapturedVars(c, n[0][1], stateIdx)
+    else:
+      detectCapturedVars(c, n[0], stateIdx)
+  else:
+    for i in 0 ..< n.safeLen:
+      detectCapturedVars(c, n[i], stateIdx)
+
+proc detectCapturedVars(c: var Ctx) =
+  for i, s in c.states:
+    detectCapturedVars(c, s.body, i)
+
+proc liftLocals(c: var Ctx, n: PNode): PNode =
+  result = n
+  case n.kind
+  of nkSym:
+    let s = n.sym
+    if c.varStates.getOrDefault(s.itemId) == localRequiresLifting:
+      # lift
+      let e = getEnvParam(c.fn)
+      let field = getFieldFromObj(e.typ.elementType, s)
+      assert(field != nil)
+      result = rawIndirectAccess(newSymNode(e), field, n.info)
+    # elif c.varStates.getOrDefault(s.itemId, localNotSeen) != localNotSeen:
+    #   echo "Not lifting ", s.name.s
+
+  of nkReturnStmt:
+    if n[0].kind in {nkAsgn, nkFastAsgn, nkSinkAsgn}:
+      # we have a `result = result` expression produced by the closure
+      # transform, let's not touch the LHS in order to make the lifting pass
+      # correct when `result` is lifted
+      n[0][1] = liftLocals(c, n[0][1])
+    else:
+      n[0] = liftLocals(c, n[0])
+  else:
+    for i in 0 ..< n.safeLen:
+      n[i] = liftLocals(c, n[i])
+
+proc transformClosureIterator*(g: ModuleGraph; idgen: IdGenerator; fn: PSym, n: PNode): PNode =
+  var ctx = Ctx(g: g, fn: fn, idgen: idgen)
+
+  # The transformation should always happen after at least partial lambdalifting
+  # is performed, so that the closure iter environment is always created upfront.
+  doAssert(getEnvParam(fn) != nil, "Env param not created before iter transformation")
 
-  if getEnvParam(fn).isNil:
-    # Lambda lifting was not done yet. Use temporary :state sym, which will
-    # be handled specially by lambda lifting. Local temp vars (if needed)
-    # should follow the same logic.
-    ctx.stateVarSym = newSym(skVar, getIdent(ctx.g.cache, ":state"), idgen, fn, fn.info)
-    ctx.stateVarSym.typ = g.createClosureIterStateType(fn, idgen)
   ctx.stateLoopLabel = newSym(skLabel, getIdent(ctx.g.cache, ":stateLoop"), idgen, fn, fn.info)
   var pc = PreprocessContext(finallys: @[], config: g.config, idgen: idgen)
   var n = preprocess(pc, n.toStmtList)
@@ -1456,17 +1513,21 @@ proc transformClosureIterator*(g: ModuleGraph; idgen: IdGenerator; fn: PSym, n:
   # Optimize empty states away
   ctx.deleteEmptyStates()
 
-  # Make new body by concatenating the list of states
-  result = newNodeI(nkStmtList, n.info)
-  for s in ctx.states:
-    assert(s.len == 2)
-    let body = s[1]
-    s.sons.del(1)
-    result.add(s)
-    result.add(body)
+  let caseDispatcher = newTreeI(nkCaseStmt, n.info,
+      ctx.newStateAccess())
 
-  result = ctx.transformStateAssignments(result)
-  result = ctx.wrapIntoStateLoop(result)
+  # Lamdalifting will not touch our locals, it is our responsibility to lift those that
+  # need it.
+  detectCapturedVars(ctx)
+
+  for s in ctx.states:
+    let body = ctx.transformStateAssignments(s.body)
+    caseDispatcher.add newTreeI(nkOfBranch, body.info, g.newIntLit(body.info, s.label), body)
+
+  caseDispatcher.add newTreeI(nkElse, n.info, newTreeI(nkReturnStmt, n.info, g.emptyNode))
+
+  result = wrapIntoStateLoop(ctx, caseDispatcher)
+  result = liftLocals(ctx, result)
 
   when false:
     echo "TRANSFORM TO STATES: "
@@ -1475,3 +1536,5 @@ proc transformClosureIterator*(g: ModuleGraph; idgen: IdGenerator; fn: PSym, n:
     echo "exception table:"
     for i, e in ctx.exceptionTable:
       echo i, " -> ", e
+
+    echo "ENV: ", renderTree(getEnvParam(fn).typ.elementType.n)

compiler/cmdlinehelper.nim

@@ -11,7 +11,9 @@
 
 import
   options, idents, nimconf, extccomp, commands, msgs,
-  lineinfos, modulegraphs, condsyms, os, pathutils, parseopt
+  lineinfos, modulegraphs, condsyms, pathutils
+
+import std/[os, parseopt]
 
 proc prependCurDir*(f: AbsoluteFile): AbsoluteFile =
   when defined(unix):

compiler/commands.nim

@@ -24,10 +24,12 @@ bootSwitch(usedMarkAndSweep, defined(gcmarkandsweep), "--gc:markAndSweep")
 bootSwitch(usedGoGC, defined(gogc), "--gc:go")
 bootSwitch(usedNoGC, defined(nogc), "--gc:none")
 
-import std/[setutils, os, strutils, parseutils, parseopt, sequtils, strtabs]
+import std/[setutils, os, strutils, parseutils, parseopt, sequtils, strtabs, enumutils]
 import
   msgs, options, nversion, condsyms, extccomp, platform,
-  wordrecg, nimblecmd, lineinfos, pathutils, pathnorm
+  wordrecg, nimblecmd, lineinfos, pathutils
+
+import std/pathnorm
 
 from ast import setUseIc, eqTypeFlags, tfGcSafe, tfNoSideEffect
 
@@ -184,7 +186,7 @@ proc processSpecificNote*(arg: string, state: TSpecialWord, pass: TCmdLinePass,
                          info: TLineInfo; orig: string; conf: ConfigRef) =
   var id = ""  # arg = key or [key] or key:val or [key]:val;  with val=on|off
   var i = 0
-  var notes: set[TMsgKind]
+  var notes: set[TMsgKind] = {}
   var isBracket = false
   if i < arg.len and arg[i] == '[':
     isBracket = true
@@ -246,6 +248,7 @@ const
   errNoneSpeedOrSizeExpectedButXFound = "'none', 'speed' or 'size' expected, but '$1' found"
   errGuiConsoleOrLibExpectedButXFound = "'gui', 'console', 'lib' or 'staticlib' expected, but '$1' found"
   errInvalidExceptionSystem = "'goto', 'setjmp', 'cpp' or 'quirky' expected, but '$1' found"
+  errInvalidFeatureButXFound = Feature.toSeq.map(proc(val:Feature): string = "'$1'" % $val).join(", ") & " expected, but '$1' found"
 
 template warningOptionNoop(switch: string) =
   warningDeprecated(conf, info, "'$#' is deprecated, now a noop" % switch)
@@ -267,13 +270,17 @@ proc testCompileOptionArg*(conf: ConfigRef; switch, arg: string, info: TLineInfo
     of "none": result = conf.selectedGC == gcNone
     of "stack", "regions": result = conf.selectedGC == gcRegions
     of "atomicarc": result = conf.selectedGC == gcAtomicArc
-    else: localError(conf, info, errNoneBoehmRefcExpectedButXFound % arg)
+    else:
+      result = false
+      localError(conf, info, errNoneBoehmRefcExpectedButXFound % arg)
   of "opt":
     case arg.normalize
     of "speed": result = contains(conf.options, optOptimizeSpeed)
     of "size": result = contains(conf.options, optOptimizeSize)
     of "none": result = conf.options * {optOptimizeSpeed, optOptimizeSize} == {}
-    else: localError(conf, info, errNoneSpeedOrSizeExpectedButXFound % arg)
+    else:
+      result = false
+      localError(conf, info, errNoneSpeedOrSizeExpectedButXFound % arg)
   of "verbosity": result = $conf.verbosity == arg
   of "app":
     case arg.normalize
@@ -283,7 +290,9 @@ proc testCompileOptionArg*(conf: ConfigRef; switch, arg: string, info: TLineInfo
                       not contains(conf.globalOptions, optGenGuiApp)
     of "staticlib": result = contains(conf.globalOptions, optGenStaticLib) and
                       not contains(conf.globalOptions, optGenGuiApp)
-    else: localError(conf, info, errGuiConsoleOrLibExpectedButXFound % arg)
+    else:
+      result = false
+      localError(conf, info, errGuiConsoleOrLibExpectedButXFound % arg)
   of "dynliboverride":
     result = isDynlibOverride(conf, arg)
   of "exceptions":
@@ -292,8 +301,18 @@ proc testCompileOptionArg*(conf: ConfigRef; switch, arg: string, info: TLineInfo
     of "setjmp": result = conf.exc == excSetjmp
     of "quirky": result = conf.exc == excQuirky
     of "goto": result = conf.exc == excGoto
-    else: localError(conf, info, errInvalidExceptionSystem % arg)
-  else: invalidCmdLineOption(conf, passCmd1, switch, info)
+    else:
+      result = false
+      localError(conf, info, errInvalidExceptionSystem % arg)
+  of "experimental":
+    try:
+      result = conf.features.contains parseEnum[Feature](arg)
+    except ValueError:
+      result = false
+      localError(conf, info, errInvalidFeatureButXFound % arg)
+  else:
+    result = false
+    invalidCmdLineOption(conf, passCmd1, switch, info)
 
 proc testCompileOption*(conf: ConfigRef; switch: string, info: TLineInfo): bool =
   case switch.normalize
@@ -339,10 +358,14 @@ proc testCompileOption*(conf: ConfigRef; switch: string, info: TLineInfo): bool
     if switch.normalize == "patterns": deprecatedAlias(switch, "trmacros")
     result = contains(conf.options, optTrMacros)
   of "excessivestacktrace": result = contains(conf.globalOptions, optExcessiveStackTrace)
-  of "nilseqs", "nilchecks", "taintmode": warningOptionNoop(switch)
+  of "nilseqs", "nilchecks", "taintmode":
+    warningOptionNoop(switch)
+    result = false
   of "panics": result = contains(conf.globalOptions, optPanics)
   of "jsbigint64": result = contains(conf.globalOptions, optJsBigInt64)
-  else: invalidCmdLineOption(conf, passCmd1, switch, info)
+  else:
+    result = false
+    invalidCmdLineOption(conf, passCmd1, switch, info)
 
 proc processPath(conf: ConfigRef; path: string, info: TLineInfo,
                  notRelativeToProj = false): AbsoluteDir =
@@ -384,7 +407,8 @@ proc makeAbsolute(s: string): AbsoluteFile =
 proc setTrackingInfo(conf: ConfigRef; dirty, file, line, column: string,
                      info: TLineInfo) =
   ## set tracking info, common code for track, trackDirty, & ideTrack
-  var ln, col: int
+  var ln: int = 0
+  var col: int = 0
   if parseUtils.parseInt(line, ln) <= 0:
     localError(conf, info, errInvalidNumber % line)
   if parseUtils.parseInt(column, col) <= 0:
@@ -449,6 +473,7 @@ proc parseCommand*(command: string): Command =
   of "objc", "compiletooc": cmdCompileToOC
   of "js", "compiletojs": cmdCompileToJS
   of "r": cmdCrun
+  of "m": cmdM
   of "run": cmdTcc
   of "check": cmdCheck
   of "e": cmdNimscript
@@ -593,10 +618,17 @@ proc processMemoryManagementOption(switch, arg: string, pass: TCmdLinePass,
       defineSymbol(conf.symbols, "gcregions")
     else: localError(conf, info, errNoneBoehmRefcExpectedButXFound % arg)
 
+proc pathRelativeToConfig(arg: string, pass: TCmdLinePass, conf: ConfigRef): string =
+  if pass == passPP and not isAbsolute(arg):
+    assert isAbsolute(conf.currentConfigDir), "something is wrong with currentConfigDir"
+    result = conf.currentConfigDir / arg
+  else:
+    result = arg
+
 proc processSwitch*(switch, arg: string, pass: TCmdLinePass, info: TLineInfo;
                     conf: ConfigRef) =
-  var
-    key, val: string
+  var key = ""
+  var val = ""
   case switch.normalize
   of "eval":
     expectArg(conf, switch, arg, pass, info)
@@ -611,8 +643,7 @@ proc processSwitch*(switch, arg: string, pass: TCmdLinePass, info: TLineInfo;
     for path in nimbleSubs(conf, arg):
       addPath(conf, if pass == passPP: processCfgPath(conf, path, info)
                     else: processPath(conf, path, info), info)
-  of "nimblepath", "babelpath":
-    if switch.normalize == "babelpath": deprecatedAlias(switch, "nimblepath")
+  of "nimblepath":
     if pass in {passCmd2, passPP} and optNoNimblePath notin conf.globalOptions:
       expectArg(conf, switch, arg, pass, info)
       var path = processPath(conf, arg, info, notRelativeToProj=true)
@@ -622,8 +653,7 @@ proc processSwitch*(switch, arg: string, pass: TCmdLinePass, info: TLineInfo;
         nimblePath(conf, path, info)
         path = nimbleDir / RelativeDir"pkgs"
       nimblePath(conf, path, info)
-  of "nonimblepath", "nobabelpath":
-    if switch.normalize == "nobabelpath": deprecatedAlias(switch, "nonimblepath")
+  of "nonimblepath":
     expectNoArg(conf, switch, arg, pass, info)
     disableNimblePath(conf)
   of "clearnimblepath":
@@ -640,7 +670,7 @@ proc processSwitch*(switch, arg: string, pass: TCmdLinePass, info: TLineInfo;
     # refs bug #18674, otherwise `--os:windows` messes up with `--nimcache` set
     # in config nims files, e.g. via: `import os; switch("nimcache", "/tmp/somedir")`
     if conf.target.targetOS == osWindows and DirSep == '/': arg = arg.replace('\\', '/')
-    conf.nimcacheDir = processPath(conf, arg, info, notRelativeToProj=true)
+    conf.nimcacheDir = processPath(conf, pathRelativeToConfig(arg, pass, conf), info, notRelativeToProj=true)
   of "out", "o":
     expectArg(conf, switch, arg, pass, info)
     let f = splitFile(processPath(conf, arg, info, notRelativeToProj=true).string)
@@ -774,7 +804,10 @@ proc processSwitch*(switch, arg: string, pass: TCmdLinePass, info: TLineInfo;
     if conf.backend == backendJs or conf.cmd == cmdNimscript: discard
     else: processOnOffSwitchG(conf, {optThreads}, arg, pass, info)
     #if optThreads in conf.globalOptions: conf.setNote(warnGcUnsafe)
-  of "tlsemulation": processOnOffSwitchG(conf, {optTlsEmulation}, arg, pass, info)
+  of "tlsemulation":
+    processOnOffSwitchG(conf, {optTlsEmulation}, arg, pass, info)
+    if optTlsEmulation in conf.globalOptions:
+      conf.legacyFeatures.incl emitGenerics
   of "implicitstatic":
     processOnOffSwitch(conf, {optImplicitStatic}, arg, pass, info)
   of "patterns", "trmacros":
@@ -882,15 +915,19 @@ proc processSwitch*(switch, arg: string, pass: TCmdLinePass, info: TLineInfo;
       defineSymbol(conf.symbols, "nodejs")
   of "maxloopiterationsvm":
     expectArg(conf, switch, arg, pass, info)
-    conf.maxLoopIterationsVM = parseInt(arg)
+    var value: int = 10_000_000
+    discard parseSaturatedNatural(arg, value)
+    if not value > 0: localError(conf, info, "maxLoopIterationsVM must be a positive integer greater than zero")
+    conf.maxLoopIterationsVM = value
   of "errormax":
     expectArg(conf, switch, arg, pass, info)
     # Note: `nim check` (etc) can overwrite this.
     # `0` is meaningless, give it a useful meaning as in clang's -ferror-limit
     # If user doesn't set this flag and the code doesn't either, it'd
     # have the same effect as errorMax = 1
-    let ret = parseInt(arg)
-    conf.errorMax = if ret == 0: high(int) else: ret
+    var value: int = 0
+    discard parseSaturatedNatural(arg, value)
+    conf.errorMax = if value == 0: high(int) else: value
   of "verbosity":
     expectArg(conf, switch, arg, pass, info)
     let verbosity = parseInt(arg)
@@ -904,7 +941,9 @@ proc processSwitch*(switch, arg: string, pass: TCmdLinePass, info: TLineInfo;
     conf.mainPackageNotes = conf.notes
   of "parallelbuild":
     expectArg(conf, switch, arg, pass, info)
-    conf.numberOfProcessors = parseInt(arg)
+    var value: int = 0
+    discard parseSaturatedNatural(arg, value)
+    conf.numberOfProcessors = value
   of "version", "v":
     expectNoArg(conf, switch, arg, pass, info)
     writeVersionInfo(conf, pass)
@@ -1113,7 +1152,8 @@ proc processSwitch*(switch, arg: string, pass: TCmdLinePass, info: TLineInfo;
     else: invalidCmdLineOption(conf, pass, switch, info)
 
 proc processCommand*(switch: string, pass: TCmdLinePass; config: ConfigRef) =
-  var cmd, arg: string
+  var cmd = ""
+  var arg = ""
   splitSwitch(config, switch, cmd, arg, pass, gCmdLineInfo)
   processSwitch(cmd, arg, pass, gCmdLineInfo, config)
 
@@ -1140,7 +1180,10 @@ proc processArgument*(pass: TCmdLinePass; p: OptParser;
       config.projectName = unixToNativePath(p.key)
       config.arguments = cmdLineRest(p)
       result = true
-    elif pass != passCmd2: setCommandEarly(config, p.key)
+    elif pass != passCmd2:
+      setCommandEarly(config, p.key)
+      result = false
+    else: result = false
   else:
     if pass == passCmd1: config.commandArgs.add p.key
     if argsCount == 1:
@@ -1151,4 +1194,6 @@ proc processArgument*(pass: TCmdLinePass; p: OptParser;
         config.projectName = unixToNativePath(p.key)
       config.arguments = cmdLineRest(p)
       result = true
+    else:
+      result = false
   inc argsCount

compiler/concepts.nim

@@ -11,9 +11,9 @@
 ## for details. Note this is a first implementation and only the "Concept matching"
 ## section has been implemented.
 
-import ast, astalgo, semdata, lookups, lineinfos, idents, msgs, renderer, types, intsets
+import ast, semdata, lookups, lineinfos, idents, msgs, renderer, types, layeredtable
 
-from magicsys import addSonSkipIntLit
+import std/intsets
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
@@ -28,23 +28,11 @@ proc declareSelf(c: PContext; info: TLineInfo) =
   ## Adds the magical 'Self' symbols to the current scope.
   let ow = getCurrOwner(c)
   let s = newSym(skType, getIdent(c.cache, "Self"), c.idgen, ow, info)
-  s.typ = newType(tyTypeDesc, nextTypeId(c.idgen), ow)
+  s.typ = newType(tyTypeDesc, c.idgen, ow)
   s.typ.flags.incl {tfUnresolved, tfPacked}
-  s.typ.add newType(tyEmpty, nextTypeId(c.idgen), ow)
+  s.typ.add newType(tyEmpty, c.idgen, ow)
   addDecl(c, s, info)
 
-proc isSelf*(t: PType): bool {.inline.} =
-  ## Is this the magical 'Self' type?
-  t.kind == tyTypeDesc and tfPacked in t.flags
-
-proc makeTypeDesc*(c: PContext, typ: PType): PType =
-  if typ.kind == tyTypeDesc and not isSelf(typ):
-    result = typ
-  else:
-    result = newTypeS(tyTypeDesc, c)
-    incl result.flags, tfCheckedForDestructor
-    result.addSonSkipIntLit(typ, c.idgen)
-
 proc semConceptDecl(c: PContext; n: PNode): PNode =
   ## Recursive helper for semantic checking for the concept declaration.
   ## Currently we only support (possibly empty) lists of statements
@@ -108,7 +96,7 @@ proc matchType(c: PContext; f, a: PType; m: var MatchCon): bool =
     ignorableForArgType = {tyVar, tySink, tyLent, tyOwned, tyGenericInst, tyAlias, tyInferred}
   case f.kind
   of tyAlias:
-    result = matchType(c, f.lastSon, a, m)
+    result = matchType(c, f.skipModifier, a, m)
   of tyTypeDesc:
     if isSelf(f):
       #let oldLen = m.inferred.len
@@ -117,15 +105,19 @@ proc matchType(c: PContext; f, a: PType; m: var MatchCon): bool =
       #m.inferred.setLen oldLen
       #echo "A for ", result, " to ", typeToString(a), " to ", typeToString(m.potentialImplementation)
     else:
-      if a.kind == tyTypeDesc and f.len == a.len:
-        for i in 0..<a.len:
-          if not matchType(c, f[i], a[i], m): return false
-        return true
+      if a.kind == tyTypeDesc and f.hasElementType == a.hasElementType:
+        if f.hasElementType:
+          result = matchType(c, f.elementType, a.elementType, m)
+        else:
+          result = true # both lack it
+      else:
+        result = false
 
   of tyGenericInvocation:
-    if a.kind == tyGenericInst and a[0].kind == tyGenericBody:
-      if sameType(f[0], a[0]) and f.len == a.len-1:
-        for i in 1 ..< f.len:
+    result = false
+    if a.kind == tyGenericInst and a.genericHead.kind == tyGenericBody:
+      if sameType(f.genericHead, a.genericHead) and f.kidsLen == a.kidsLen-1:
+        for i in FirstGenericParamAt ..< f.kidsLen:
           if not matchType(c, f[i], a[i], m): return false
         return true
   of tyGenericParam:
@@ -135,17 +127,17 @@ proc matchType(c: PContext; f, a: PType; m: var MatchCon): bool =
     else:
       let old = existingBinding(m, f)
       if old == nil:
-        if f.len > 0 and f[0].kind != tyNone:
+        if f.hasElementType and f.elementType.kind != tyNone:
           # also check the generic's constraints:
           let oldLen = m.inferred.len
-          result = matchType(c, f[0], a, m)
+          result = matchType(c, f.elementType, a, m)
           m.inferred.setLen oldLen
           if result:
             when logBindings: echo "A adding ", f, " ", ak
             m.inferred.add((f, ak))
         elif m.magic == mArrGet and ak.kind in {tyArray, tyOpenArray, tySequence, tyVarargs, tyCstring, tyString}:
           when logBindings: echo "B adding ", f, " ", lastSon ak
-          m.inferred.add((f, lastSon ak))
+          m.inferred.add((f, last ak))
           result = true
         else:
           when logBindings: echo "C adding ", f, " ", ak
@@ -156,15 +148,17 @@ proc matchType(c: PContext; f, a: PType; m: var MatchCon): bool =
         result = matchType(c, old, ak, m)
         if m.magic == mArrPut and ak.kind == tyGenericParam:
           result = true
+      else:
+        result = false
     #echo "B for ", result, " to ", typeToString(a), " to ", typeToString(m.potentialImplementation)
 
   of tyVar, tySink, tyLent, tyOwned:
     # modifiers in the concept must be there in the actual implementation
     # too but not vice versa.
     if a.kind == f.kind:
-      result = matchType(c, f.sons[0], a.sons[0], m)
+      result = matchType(c, f.elementType, a.elementType, m)
     elif m.magic == mArrPut:
-      result = matchType(c, f.sons[0], a, m)
+      result = matchType(c, f.elementType, a, m)
     else:
       result = false
   of tyEnum, tyObject, tyDistinct:
@@ -174,7 +168,7 @@ proc matchType(c: PContext; f, a: PType; m: var MatchCon): bool =
   of tyBool, tyChar, tyInt..tyUInt64:
     let ak = a.skipTypes(ignorableForArgType)
     result = ak.kind == f.kind or ak.kind == tyOrdinal or
-       (ak.kind == tyGenericParam and ak.len > 0 and ak[0].kind == tyOrdinal)
+       (ak.kind == tyGenericParam and ak.hasElementType and ak.elementType.kind == tyOrdinal)
   of tyConcept:
     let oldLen = m.inferred.len
     let oldPotentialImplementation = m.potentialImplementation
@@ -185,9 +179,11 @@ proc matchType(c: PContext; f, a: PType; m: var MatchCon): bool =
       m.inferred.setLen oldLen
   of tyArray, tyTuple, tyVarargs, tyOpenArray, tyRange, tySequence, tyRef, tyPtr,
      tyGenericInst:
+    # ^ XXX Rewrite this logic, it's more complex than it needs to be.
+    result = false
     let ak = a.skipTypes(ignorableForArgType - {f.kind})
-    if ak.kind == f.kind and f.len == ak.len:
-      for i in 0..<ak.len:
+    if ak.kind == f.kind and f.kidsLen == ak.kidsLen:
+      for i in 0..<ak.kidsLen:
         if not matchType(c, f[i], ak[i], m): return false
       return true
   of tyOr:
@@ -196,29 +192,30 @@ proc matchType(c: PContext; f, a: PType; m: var MatchCon): bool =
       # say the concept requires 'int|float|string' if the potentialImplementation
       # says 'int|string' that is good enough.
       var covered = 0
-      for i in 0..<f.len:
-        for j in 0..<a.len:
+      for ff in f.kids:
+        for aa in a.kids:
           let oldLenB = m.inferred.len
-          let r = matchType(c, f[i], a[j], m)
+          let r = matchType(c, ff, aa, m)
           if r:
             inc covered
             break
           m.inferred.setLen oldLenB
 
-      result = covered >= a.len
+      result = covered >= a.kidsLen
       if not result:
         m.inferred.setLen oldLen
     else:
-      for i in 0..<f.len:
-        result = matchType(c, f[i], a, m)
+      result = false
+      for ff in f.kids:
+        result = matchType(c, ff, a, m)
         if result: break # and remember the binding!
         m.inferred.setLen oldLen
   of tyNot:
     if a.kind == tyNot:
-      result = matchType(c, f[0], a[0], m)
+      result = matchType(c, f.elementType, a.elementType, m)
     else:
       let oldLen = m.inferred.len
-      result = not matchType(c, f[0], a, m)
+      result = not matchType(c, f.elementType, a, m)
       m.inferred.setLen oldLen
   of tyAnything:
     result = true
@@ -257,7 +254,7 @@ proc matchSym(c: PContext; candidate: PSym, n: PNode; m: var MatchCon): bool =
       m.inferred.setLen oldLen
       return false
 
-  if not matchReturnType(c, n[0].sym.typ.sons[0], candidate.typ.sons[0], m):
+  if not matchReturnType(c, n[0].sym.typ.returnType, candidate.typ.returnType, m):
     m.inferred.setLen oldLen
     return false
 
@@ -312,7 +309,7 @@ proc conceptMatchNode(c: PContext; n: PNode; m: var MatchCon): bool =
     # error was reported earlier.
     result = false
 
-proc conceptMatch*(c: PContext; concpt, arg: PType; bindings: var TIdTable; invocation: PType): bool =
+proc conceptMatch*(c: PContext; concpt, arg: PType; bindings: var LayeredIdTable; invocation: PType): bool =
   ## Entry point from sigmatch. 'concpt' is the concept we try to match (here still a PType but
   ## we extract its AST via 'concpt.n.lastSon'). 'arg' is the type that might fulfill the
   ## concept's requirements. If so, we return true and fill the 'bindings' with pairs of
@@ -331,16 +328,16 @@ proc conceptMatch*(c: PContext; concpt, arg: PType; bindings: var TIdTable; invo
           dest = existingBinding(m, dest)
           if dest == nil or dest.kind != tyGenericParam: break
         if dest != nil:
-          bindings.idTablePut(a, dest)
+          bindings.put(a, dest)
           when logBindings: echo "A bind ", a, " ", dest
       else:
-        bindings.idTablePut(a, b)
+        bindings.put(a, b)
         when logBindings: echo "B bind ", a, " ", b
     # we have a match, so bind 'arg' itself to 'concpt':
-    bindings.idTablePut(concpt, arg)
+    bindings.put(concpt, arg)
     # invocation != nil means we have a non-atomic concept:
-    if invocation != nil and arg.kind == tyGenericInst and invocation.len == arg.len-1:
+    if invocation != nil and arg.kind == tyGenericInst and invocation.kidsLen == arg.kidsLen-1:
       # bind even more generic parameters
       assert invocation.kind == tyGenericInvocation
-      for i in 1 ..< invocation.len:
-        bindings.idTablePut(invocation[i], arg[i])
+      for i in FirstGenericParamAt ..< invocation.kidsLen:
+        bindings.put(invocation[i], arg[i])

compiler/condsyms.nim

@@ -10,7 +10,7 @@
 # This module handles the conditional symbols.
 
 import
-  strtabs
+  std/strtabs
 
 from options import Feature
 from lineinfos import hintMin, hintMax, warnMin, warnMax
@@ -143,7 +143,6 @@ proc initDefines*(symbols: StringTableRef) =
   defineSymbol("nimHasTemplateRedefinitionPragma")
   defineSymbol("nimHasCstringCase")
   defineSymbol("nimHasCallsitePragma")
-  defineSymbol("nimHasAmbiguousEnumHint")
 
   defineSymbol("nimHasWarnCastSizes") # deadcode
   defineSymbol("nimHasOutParams")
@@ -160,4 +159,15 @@ proc initDefines*(symbols: StringTableRef) =
   defineSymbol("nimHasEnsureMove")
   defineSymbol("nimHasNoReturnError")
 
+  defineSymbol("nimUseStrictDefs")
+  defineSymbol("nimHasNolineTooLong")
+
   defineSymbol("nimHasCastExtendedVm")
+  defineSymbol("nimHasWarnStdPrefix")
+
+  defineSymbol("nimHasVtables")
+  defineSymbol("nimHasGenericsOpenSym2")
+  defineSymbol("nimHasGenericsOpenSym3")
+  defineSymbol("nimHasJsNoLambdaLifting")
+  defineSymbol("nimHasDefaultFloatRoundtrip")
+  defineSymbol("nimHasXorSet")

compiler/depends.nim

@@ -14,7 +14,7 @@ import options, ast, ropes, pathutils, msgs, lineinfos
 import modulegraphs
 
 import std/[os, parseutils]
-import strutils except addf
+import std/strutils except addf
 import std/private/globs
 
 when defined(nimPreviewSlimSystem):
@@ -42,7 +42,7 @@ proc toNimblePath(s: string, isStdlib: bool): string =
     let sub = "lib/"
     var start = s.find(sub)
     if start < 0:
-      doAssert false
+      raiseAssert "unreachable"
     else:
       start += sub.len
       let base = s[start..^1]
@@ -105,11 +105,6 @@ proc generateDot*(graph: ModuleGraph; project: AbsoluteFile) =
             changeFileExt(project, "dot"))
 
 proc setupDependPass*(graph: ModuleGraph; module: PSym; idgen: IdGenerator): PPassContext =
-  var g: PGen
-  new(g)
-  g.module = module
-  g.config = graph.config
-  g.graph = graph
+  result = PGen(module: module, config: graph.config, graph: graph)
   if graph.backend == nil:
     graph.backend = Backend(dotGraph: "")
-  result = g

compiler/dfa.nim

@@ -22,8 +22,9 @@
 ## "A Graph–Free Approach to Data–Flow Analysis" by Markus Mohnen.
 ## https://link.springer.com/content/pdf/10.1007/3-540-45937-5_6.pdf
 
-import ast, intsets, lineinfos, renderer, aliasanalysis
+import ast, lineinfos, renderer, aliasanalysis
 import std/private/asciitables
+import std/intsets
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
@@ -45,10 +46,10 @@ type
     case isTryBlock: bool
     of false:
       label: PSym
-      breakFixups: seq[(TPosition, seq[PNode])] #Contains the gotos for the breaks along with their pending finales
+      breakFixups: seq[(TPosition, seq[PNode])] # Contains the gotos for the breaks along with their pending finales
     of true:
       finale: PNode
-      raiseFixups: seq[TPosition] #Contains the gotos for the raises
+      raiseFixups: seq[TPosition] # Contains the gotos for the raises
 
   Con = object
     code: ControlFlowGraph
@@ -60,6 +61,7 @@ type
 proc codeListing(c: ControlFlowGraph, start = 0; last = -1): string =
   # for debugging purposes
   # first iteration: compute all necessary labels:
+  result = ""
   var jumpTargets = initIntSet()
   let last = if last < 0: c.len-1 else: min(last, c.len-1)
   for i in start..last:
@@ -111,7 +113,7 @@ proc patch(c: var Con, p: TPosition) =
 proc gen(c: var Con; n: PNode)
 
 proc popBlock(c: var Con; oldLen: int) =
-  var exits: seq[TPosition]
+  var exits: seq[TPosition] = @[]
   exits.add c.gotoI()
   for f in c.blocks[oldLen].breakFixups:
     c.patch(f[0])
@@ -128,10 +130,6 @@ template withBlock(labl: PSym; body: untyped) =
   body
   popBlock(c, oldLen)
 
-proc isTrue(n: PNode): bool =
-  n.kind == nkSym and n.sym.kind == skEnumField and n.sym.position != 0 or
-    n.kind == nkIntLit and n.intVal != 0
-
 template forkT(body) =
   let lab1 = c.forkI()
   body
@@ -183,14 +181,6 @@ proc genIf(c: var Con, n: PNode) =
     goto Lend3
   L3:
     D
-    goto Lend3 # not eliminated to simplify the join generation
-  Lend3:
-    join F3
-  Lend2:
-    join F2
-  Lend:
-    join F1
-
   ]#
   var endings: seq[TPosition] = @[]
   let oldInteresting = c.interestingInstructions
@@ -215,7 +205,6 @@ proc genAndOr(c: var Con; n: PNode) =
   #   fork lab1
   #   asgn dest, b
   # lab1:
-  #   join F1
   c.gen(n[1])
   forkT:
     c.gen(n[2])
@@ -263,7 +252,7 @@ proc genBreakOrRaiseAux(c: var Con, i: int, n: PNode) =
   if c.blocks[i].isTryBlock:
     c.blocks[i].raiseFixups.add lab1
   else:
-    var trailingFinales: seq[PNode]
+    var trailingFinales: seq[PNode] = @[]
     if c.inTryStmt > 0:
       # Ok, we are in a try, lets see which (if any) try's we break out from:
       for b in countdown(c.blocks.high, i):
@@ -326,7 +315,7 @@ proc genRaise(c: var Con; n: PNode) =
       if c.blocks[i].isTryBlock:
         genBreakOrRaiseAux(c, i, n)
         return
-    assert false #Unreachable
+    assert false # Unreachable
   else:
     genNoReturn(c)
 
@@ -382,7 +371,7 @@ proc genCall(c: var Con; n: PNode) =
   if t != nil: t = t.skipTypes(abstractInst)
   for i in 1..<n.len:
     gen(c, n[i])
-    if t != nil and i < t.len and isOutParam(t[i]):
+    if t != nil and i < t.signatureLen and isOutParam(t[i]):
       # Pass by 'out' is a 'must def'. Good enough for a move optimizer.
       genDef(c, n[i])
   # every call can potentially raise:
@@ -392,7 +381,6 @@ proc genCall(c: var Con; n: PNode) =
     # fork lab1
     # goto exceptionHandler (except or finally)
     # lab1:
-    # join F1
     forkT:
       for i in countdown(c.blocks.high, 0):
         if c.blocks[i].isTryBlock:
@@ -469,7 +457,7 @@ proc gen(c: var Con; n: PNode) =
   of nkConv, nkExprColonExpr, nkExprEqExpr, nkCast, PathKinds1:
     gen(c, n[1])
   of nkVarSection, nkLetSection: genVarSection(c, n)
-  of nkDefer: doAssert false, "dfa construction pass requires the elimination of 'defer'"
+  of nkDefer: raiseAssert "dfa construction pass requires the elimination of 'defer'"
   else: discard
 
 when false:

compiler/docgen.nim

@@ -15,15 +15,16 @@
 ## For corresponding users' documentation see [Nim DocGen Tools Guide].
 
 import
-  ast, strutils, strtabs, algorithm, sequtils, options, msgs, os, idents,
+  ast, options, msgs, idents,
   wordrecg, syntaxes, renderer, lexer,
   packages/docutils/[rst, rstidx, rstgen, dochelpers],
-  json, xmltree, trees, types,
-  typesrenderer, astalgo, lineinfos, intsets,
-  pathutils, tables, nimpaths, renderverbatim, osproc, packages
+  trees, types,
+  typesrenderer, astalgo, lineinfos,
+  pathutils, nimpaths, renderverbatim, packages
 import packages/docutils/rstast except FileIndex, TLineInfo
 
-from uri import encodeUrl
+import std/[os, strutils, strtabs, algorithm, json, osproc, tables, intsets, xmltree, sequtils]
+from std/uri import encodeUrl
 from nodejs import findNodeJs
 
 when defined(nimPreviewSlimSystem):
@@ -114,7 +115,7 @@ proc add(dest: var ItemPre, str: string) = dest.add ItemFragment(isRst: false, s
 
 proc addRstFileIndex(d: PDoc, fileIndex: lineinfos.FileIndex): rstast.FileIndex =
   let invalid = rstast.FileIndex(-1)
-  result = d.nimToRstFid.getOrDefault(fileIndex, default = invalid)
+  result = d.nimToRstFid.getOrDefault(fileIndex, invalid)
   if result == invalid:
     let fname = toFullPath(d.conf, fileIndex)
     result = addFilename(d.sharedState, fname)
@@ -170,6 +171,7 @@ proc cmpDecimalsIgnoreCase(a, b: string): int =
 
 proc prettyString(a: object): string =
   # xxx pending std/prettyprint refs https://github.com/nim-lang/RFCs/issues/203#issuecomment-602534906
+  result = ""
   for k, v in fieldPairs(a):
     result.add k & ": " & $v & "\n"
 
@@ -215,12 +217,16 @@ proc whichType(d: PDoc; n: PNode): PSym =
   if n.kind == nkSym:
     if d.types.strTableContains(n.sym):
       result = n.sym
+    else:
+      result = nil
   else:
+    result = nil
     for i in 0..<n.safeLen:
       let x = whichType(d, n[i])
       if x != nil: return x
 
 proc attachToType(d: PDoc; p: PSym): PSym =
+  result = nil
   let params = p.ast[paramsPos]
   template check(i) =
     result = whichType(d, params[i])
@@ -283,7 +289,7 @@ template declareClosures(currentFilename: AbsoluteFile, destFile: string) =
     let outDirPath: RelativeFile =
         presentationPath(conf, AbsoluteFile(basedir / targetRelPath))
           # use presentationPath because `..` path can be be mangled to `_._`
-    result.targetPath = string(conf.outDir / outDirPath)
+    result = (string(conf.outDir / outDirPath), "")
     if not fileExists(result.targetPath):
       # this can happen if targetRelPath goes to parent directory `OUTDIR/..`.
       # Trying it, this may cause ambiguities, but allows us to insert
@@ -343,7 +349,7 @@ proc newDocumentor*(filename: AbsoluteFile; cache: IdentCache; conf: ConfigRef,
 
   if conf.configVars.hasKey("doc.googleAnalytics") and
       conf.configVars.hasKey("doc.plausibleAnalytics"):
-    doAssert false, "Either use googleAnalytics or plausibleAnalytics"
+    raiseAssert "Either use googleAnalytics or plausibleAnalytics"
 
   if conf.configVars.hasKey("doc.googleAnalytics"):
     result.analytics = """
@@ -368,7 +374,7 @@ proc newDocumentor*(filename: AbsoluteFile; cache: IdentCache; conf: ConfigRef,
   result.seenSymbols = newStringTable(modeCaseInsensitive)
   result.id = 100
   result.jEntriesFinal = newJArray()
-  initStrTable result.types
+  result.types = initStrTable()
   result.onTestSnippet =
     proc (gen: var RstGenerator; filename, cmd: string; status: int; content: string) {.gcsafe.} =
       if conf.docCmd == docCmdSkip: return
@@ -435,6 +441,8 @@ proc genComment(d: PDoc, n: PNode): PRstNode =
                         d.conf, d.sharedState)
     except ERecoverableError:
       result = newRstNode(rnLiteralBlock, @[newRstLeaf(n.comment)])
+  else:
+    result = nil
 
 proc genRecCommentAux(d: PDoc, n: PNode): PRstNode =
   if n == nil: return nil
@@ -469,6 +477,7 @@ proc getPlainDocstring(n: PNode): string =
   elif startsWith(n.comment, "##"):
     result = n.comment
   else:
+    result = ""
     for i in 0..<n.safeLen:
       result = getPlainDocstring(n[i])
       if result.len > 0: return
@@ -484,9 +493,8 @@ proc externalDep(d: PDoc; module: PSym): string =
 proc nodeToHighlightedHtml(d: PDoc; n: PNode; result: var string;
                            renderFlags: TRenderFlags = {};
                            procLink: string) =
-  var r: TSrcGen
+  var r: TSrcGen = initTokRender(n, renderFlags)
   var literal = ""
-  initTokRender(r, n, renderFlags)
   var kind = tkEof
   var tokenPos = 0
   var procTokenPos = 0
@@ -600,7 +608,9 @@ proc runAllExamples(d: PDoc) =
       rawMessage(d.conf, hintSuccess, ["runnableExamples: " & outp.string])
       # removeFile(outp.changeFileExt(ExeExt)) # it's in nimcache, no need to remove
 
-proc quoted(a: string): string = result.addQuoted(a)
+proc quoted(a: string): string =
+  result = ""
+  result.addQuoted(a)
 
 proc toInstantiationInfo(conf: ConfigRef, info: TLineInfo): (string, int, int) =
   # xxx expose in compiler/lineinfos.nim
@@ -726,7 +736,7 @@ proc getAllRunnableExamplesImpl(d: PDoc; n: PNode, dest: var ItemPre,
         let (rdoccmd, code) = prepareExample(d, n, topLevel)
         var msg = "Example:"
         if rdoccmd.len > 0: msg.add " cmd: " & rdoccmd
-        var s: string
+        var s: string = ""
         dispA(d.conf, s, "\n<p><strong class=\"examples_text\">$1</strong></p>\n",
             "\n\n\\textbf{$1}\n", [msg])
         dest.add s
@@ -820,8 +830,8 @@ proc getName(n: PNode): string =
   of nkAccQuoted:
     result = "`"
     for i in 0..<n.len: result.add(getName(n[i]))
-    result = "`"
-  of nkOpenSymChoice, nkClosedSymChoice:
+    result.add('`')
+  of nkOpenSymChoice, nkClosedSymChoice, nkOpenSym:
     result = getName(n[0])
   else:
     result = ""
@@ -839,7 +849,7 @@ proc getNameIdent(cache: IdentCache; n: PNode): PIdent =
     var r = ""
     for i in 0..<n.len: r.add(getNameIdent(cache, n[i]).s)
     result = getIdent(cache, r)
-  of nkOpenSymChoice, nkClosedSymChoice:
+  of nkOpenSymChoice, nkClosedSymChoice, nkOpenSym:
     result = getNameIdent(cache, n[0])
   else:
     result = nil
@@ -853,7 +863,7 @@ proc getRstName(n: PNode): PRstNode =
   of nkAccQuoted:
     result = getRstName(n[0])
     for i in 1..<n.len: result.text.add(getRstName(n[i]).text)
-  of nkOpenSymChoice, nkClosedSymChoice:
+  of nkOpenSymChoice, nkClosedSymChoice, nkOpenSym:
     result = getRstName(n[0])
   else:
     result = nil
@@ -942,14 +952,17 @@ proc genDeprecationMsg(d: PDoc, n: PNode): string =
     if n[1].kind in {nkStrLit..nkTripleStrLit}:
       result = getConfigVar(d.conf, "doc.deprecationmsg") % [
           "label", "Deprecated:", "message", xmltree.escape(n[1].strVal)]
+    else:
+      result = ""
   else:
-    doAssert false
+    raiseAssert "unreachable"
 
 type DocFlags = enum
   kDefault
   kForceExport
 
 proc genSeeSrc(d: PDoc, path: string, line: int): string =
+  result = ""
   let docItemSeeSrc = getConfigVar(d.conf, "doc.item.seesrc")
   if docItemSeeSrc.len > 0:
     let path = relativeTo(AbsoluteFile path, AbsoluteDir getCurrentDir(), '/')
@@ -987,11 +1000,12 @@ proc getTypeKind(n: PNode): string =
 proc toLangSymbol(k: TSymKind, n: PNode, baseName: string): LangSymbol =
   ## Converts symbol info (names/types/parameters) in `n` into format
   ## `LangSymbol` convenient for ``rst.nim``/``dochelpers.nim``.
-  result.name = baseName.nimIdentNormalize
-  result.symKind = k.toHumanStr
+  result = LangSymbol(name: baseName.nimIdentNormalize,
+      symKind: k.toHumanStr
+  )
   if k in routineKinds:
     var
-      paramTypes: seq[string]
+      paramTypes: seq[string] = @[]
     renderParamTypes(paramTypes, n[paramsPos], toNormalize=true)
     let paramNames = renderParamNames(n[paramsPos], toNormalize=true)
     # In some rare cases (system.typeof) parameter type is not set for default:
@@ -1016,9 +1030,8 @@ proc toLangSymbol(k: TSymKind, n: PNode, baseName: string): LangSymbol =
         genNode = n[miscPos][1]   # FIXME: what is index 1?
     if genNode != nil:
       var literal = ""
-      var r: TSrcGen
-      initTokRender(r, genNode, {renderNoBody, renderNoComments,
-        renderNoPragmas, renderNoProcDefs, renderExpandUsing})
+      var r: TSrcGen = initTokRender(genNode, {renderNoBody, renderNoComments,
+        renderNoPragmas, renderNoProcDefs, renderExpandUsing, renderNoPostfix})
       var kind = tkEof
       while true:
         getNextTok(r, kind, literal)
@@ -1038,16 +1051,15 @@ proc genItem(d: PDoc, n, nameNode: PNode, k: TSymKind, docFlags: DocFlags, nonEx
   var result = ""
   var literal, plainName = ""
   var kind = tkEof
-  var comm: ItemPre
+  var comm: ItemPre = default(ItemPre)
   if n.kind in routineDefs:
     getAllRunnableExamples(d, n, comm)
   else:
     comm.add genRecComment(d, n)
 
-  var r: TSrcGen
   # Obtain the plain rendered string for hyperlink titles.
-  initTokRender(r, n, {renderNoBody, renderNoComments, renderDocComments,
-    renderNoPragmas, renderNoProcDefs, renderExpandUsing})
+  var r: TSrcGen = initTokRender(n, {renderNoBody, renderNoComments, renderDocComments,
+    renderNoPragmas, renderNoProcDefs, renderExpandUsing, renderNoPostfix})
   while true:
     getNextTok(r, kind, literal)
     if kind == tkEof:
@@ -1074,6 +1086,9 @@ proc genItem(d: PDoc, n, nameNode: PNode, k: TSymKind, docFlags: DocFlags, nonEx
     symbolOrIdEnc = encodeUrl(symbolOrId, usePlus = false)
     deprecationMsg = genDeprecationMsg(d, pragmaNode)
     rstLangSymbol = toLangSymbol(k, n, cleanPlainSymbol)
+    symNameNode =
+      if nameNode.kind == nkPostfix: nameNode[1]
+      else: nameNode
 
   # we generate anchors automatically for subsequent use in doc comments
   let lineinfo = rstast.TLineInfo(
@@ -1084,10 +1099,10 @@ proc genItem(d: PDoc, n, nameNode: PNode, k: TSymKind, docFlags: DocFlags, nonEx
                priority = symbolPriority(k), info = lineinfo,
                module = addRstFileIndex(d, FileIndex d.module.position))
 
-  let renderFlags =
-    if nonExports: {renderNoBody, renderNoComments, renderDocComments, renderSyms,
-      renderExpandUsing, renderNonExportedFields}
-    else: {renderNoBody, renderNoComments, renderDocComments, renderSyms, renderExpandUsing}
+  var renderFlags = {renderNoBody, renderNoComments, renderDocComments,
+    renderSyms, renderExpandUsing, renderNoPostfix}
+  if nonExports:
+    renderFlags.incl renderNonExportedFields
   nodeToHighlightedHtml(d, n, result, renderFlags, symbolOrIdEnc)
 
   let seeSrc = genSeeSrc(d, toFullPath(d.conf, n.info), n.info.line.int)
@@ -1110,18 +1125,19 @@ proc genItem(d: PDoc, n, nameNode: PNode, k: TSymKind, docFlags: DocFlags, nonEx
   let external = d.destFile.AbsoluteFile.relativeTo(d.conf.outDir, '/').changeFileExt(HtmlExt).string
 
   var attype = ""
-  if k in routineKinds and nameNode.kind == nkSym:
+  if k in routineKinds and symNameNode.kind == nkSym:
     let att = attachToType(d, nameNode.sym)
     if att != nil:
       attype = esc(d.target, att.name.s)
-  elif k == skType and nameNode.kind == nkSym and nameNode.sym.typ.kind in {tyEnum, tyBool}:
-    let etyp = nameNode.sym.typ
+  elif k == skType and symNameNode.kind == nkSym and
+      symNameNode.sym.typ.kind in {tyEnum, tyBool}:
+    let etyp = symNameNode.sym.typ
     for e in etyp.n:
       if e.sym.kind != skEnumField: continue
       let plain = renderPlainSymbolName(e)
       let symbolOrId = d.newUniquePlainSymbol(plain)
       setIndexTerm(d[], ieNim, htmlFile = external, id = symbolOrId,
-                   term = plain, linkTitle = nameNode.sym.name.s & '.' & plain,
+                   term = plain, linkTitle = symNameNode.sym.name.s & '.' & plain,
                    linkDesc = xmltree.escape(getPlainDocstring(e).docstringSummary),
                    line = n.info.line.int)
 
@@ -1142,8 +1158,8 @@ proc genItem(d: PDoc, n, nameNode: PNode, k: TSymKind, docFlags: DocFlags, nonEx
                linkTitle = detailedName,
                linkDesc = xmltree.escape(plainDocstring.docstringSummary),
                line = n.info.line.int)
-  if k == skType and nameNode.kind == nkSym:
-    d.types.strTableAdd nameNode.sym
+  if k == skType and symNameNode.kind == nkSym:
+    d.types.strTableAdd symNameNode.sym
 
 proc genJsonItem(d: PDoc, n, nameNode: PNode, k: TSymKind, nonExports = false): JsonItem =
   if not isVisible(d, nameNode): return
@@ -1151,12 +1167,14 @@ proc genJsonItem(d: PDoc, n, nameNode: PNode, k: TSymKind, nonExports = false):
     name = getNameEsc(d, nameNode)
     comm = genRecComment(d, n)
     r: TSrcGen
-    renderFlags = {renderNoBody, renderNoComments, renderDocComments, renderExpandUsing}
+    renderFlags = {renderNoBody, renderNoComments, renderDocComments,
+      renderExpandUsing, renderNoPostfix}
   if nonExports:
     renderFlags.incl renderNonExportedFields
-  initTokRender(r, n, renderFlags)
-  result.json = %{ "name": %name, "type": %($k), "line": %n.info.line.int,
+  r = initTokRender(n, renderFlags)
+  result = JsonItem(json: %{ "name": %name, "type": %($k), "line": %n.info.line.int,
                    "col": %n.info.col}
+  )
   if comm != nil:
     result.rst = comm
     result.rstField = "description"
@@ -1186,10 +1204,9 @@ proc genJsonItem(d: PDoc, n, nameNode: PNode, k: TSymKind, nonExports = false):
       result.json["signature"]["genericParams"] = newJArray()
       for genericParam in n[genericParamsPos]:
         var param = %{"name": %($genericParam)}
-        if genericParam.sym.typ.sons.len > 0:
+        if genericParam.sym.typ.len > 0:
           param["types"] = newJArray()
-        for kind in genericParam.sym.typ.sons:
-          param["types"].add %($kind)
+          param["types"] = %($genericParam.sym.typ.elementType)
         result.json["signature"]["genericParams"].add param
   if optGenIndex in d.conf.globalOptions:
     genItem(d, n, nameNode, k, kForceExport)
@@ -1283,6 +1300,8 @@ proc documentNewEffect(cache: IdentCache; n: PNode): PNode =
   let s = n[namePos].sym
   if tfReturnsNew in s.typ.flags:
     result = newIdentNode(getIdent(cache, "new"), n.info)
+  else:
+    result = nil
 
 proc documentEffect(cache: IdentCache; n, x: PNode, effectType: TSpecialWord, idx: int): PNode =
   let spec = effectSpec(x, effectType)
@@ -1301,10 +1320,12 @@ proc documentEffect(cache: IdentCache; n, x: PNode, effectType: TSpecialWord, id
       if t.startsWith("ref "): t = substr(t, 4)
       effects[i] = newIdentNode(getIdent(cache, t), n.info)
       # set the type so that the following analysis doesn't screw up:
-      effects[i].typ = real[i].typ
+      effects[i].typ() = real[i].typ
 
     result = newTreeI(nkExprColonExpr, n.info,
       newIdentNode(getIdent(cache, $effectType), n.info), effects)
+  else:
+    result = nil
 
 proc documentWriteEffect(cache: IdentCache; n: PNode; flag: TSymFlag; pragmaName: string): PNode =
   let s = n[namePos].sym
@@ -1318,6 +1339,8 @@ proc documentWriteEffect(cache: IdentCache; n: PNode; flag: TSymFlag; pragmaName
   if effects.len > 0:
     result = newTreeI(nkExprColonExpr, n.info,
       newIdentNode(getIdent(cache, pragmaName), n.info), effects)
+  else:
+    result = nil
 
 proc documentRaises*(cache: IdentCache; n: PNode) =
   if n[namePos].kind != nkSym: return
@@ -1383,7 +1406,8 @@ proc generateDoc*(d: PDoc, n, orig: PNode, config: ConfigRef, docFlags: DocFlags
     for it in n: traceDeps(d, it)
   of nkExportStmt:
     for it in n:
-      if it.kind == nkSym:
+      # bug #23051; don't generate documentation for exported symbols again
+      if it.kind == nkSym and sfExported notin it.sym.flags:
         if d.module != nil and d.module == it.sym.owner:
           generateDoc(d, it.sym.ast, orig, config, kForceExport)
         elif it.sym.ast != nil:
@@ -1391,7 +1415,7 @@ proc generateDoc*(d: PDoc, n, orig: PNode, config: ConfigRef, docFlags: DocFlags
   of nkExportExceptStmt: discard "transformed into nkExportStmt by semExportExcept"
   of nkFromStmt, nkImportExceptStmt: traceDeps(d, n[0])
   of nkCallKinds:
-    var comm: ItemPre
+    var comm: ItemPre = default(ItemPre)
     getAllRunnableExamples(d, n, comm)
     if comm.len != 0: d.modDescPre.add(comm)
   else: discard
@@ -1500,7 +1524,7 @@ proc finishGenerateDoc*(d: var PDoc) =
       overloadChoices.sort(cmp)
       var nameContent = ""
       for item in overloadChoices:
-        var itemDesc: string
+        var itemDesc: string = ""
         renderItemPre(d, item.descRst, itemDesc)
         nameContent.add(
           getConfigVar(d.conf, "doc.item") % (
@@ -1526,7 +1550,7 @@ proc finishGenerateDoc*(d: var PDoc) =
   for i, entry in d.jEntriesPre:
     if entry.rst != nil:
       let resolved = resolveSubs(d.sharedState, entry.rst)
-      var str: string
+      var str: string = ""
       renderRstToOut(d[], resolved, str)
       entry.json[entry.rstField] = %str
       d.jEntriesPre[i].rst = nil
@@ -1641,7 +1665,7 @@ proc genSection(d: PDoc, kind: TSymKind, groupedToc = false) =
     for plainName in overloadableNames.sorted(cmpDecimalsIgnoreCase):
       var overloadChoices = d.tocTable[kind][plainName]
       overloadChoices.sort(cmp)
-      var content: string
+      var content: string = ""
       for item in overloadChoices:
         content.add item.content
       d.toc2[kind].add getConfigVar(d.conf, "doc.section.toc2") % [
@@ -1672,7 +1696,7 @@ proc relLink(outDir: AbsoluteDir, destFile: AbsoluteFile, linkto: RelativeFile):
 
 proc genOutFile(d: PDoc, groupedToc = false): string =
   var
-    code, content: string
+    code, content: string = ""
     title = ""
   var j = 0
   var toc = ""
@@ -1781,7 +1805,7 @@ proc writeOutput*(d: PDoc, useWarning = false, groupedToc = false) =
 
 proc writeOutputJson*(d: PDoc, useWarning = false) =
   runAllExamples(d)
-  var modDesc: string
+  var modDesc: string = ""
   for desc in d.modDescFinal:
     modDesc &= desc
   let content = %*{"orig": d.filename,
@@ -1789,11 +1813,11 @@ proc writeOutputJson*(d: PDoc, useWarning = false) =
     "moduleDescription": modDesc,
     "entries": d.jEntriesFinal}
   if optStdout in d.conf.globalOptions:
-    write(stdout, $content)
+    writeLine(stdout, $content)
   else:
     let dir = d.destFile.splitFile.dir
     createDir(dir)
-    var f: File
+    var f: File = default(File)
     if open(f, d.destFile, fmWrite):
       write(f, $content)
       close(f)

compiler/docgen2.nim

@@ -39,10 +39,12 @@ template closeImpl(body: untyped) {.dirty.} =
       discard
 
 proc closeDoc*(graph: ModuleGraph; p: PPassContext, n: PNode): PNode =
+  result = nil
   closeImpl:
     writeOutput(g.doc, useWarning, groupedToc)
 
 proc closeJson*(graph: ModuleGraph; p: PPassContext, n: PNode): PNode =
+  result = nil
   closeImpl:
     writeOutputJson(g.doc, useWarning)
 

compiler/enumtostr.nim

@@ -14,7 +14,7 @@ proc genEnumToStrProc*(t: PType; info: TLineInfo; g: ModuleGraph; idgen: IdGener
   let res = newSym(skResult, getIdent(g.cache, "result"), idgen, result, info)
   res.typ = getSysType(g, info, tyString)
 
-  result.typ = newType(tyProc, nextTypeId idgen, t.owner)
+  result.typ = newType(tyProc, idgen, t.owner)
   result.typ.n = newNodeI(nkFormalParams, info)
   rawAddSon(result.typ, res.typ)
   result.typ.n.add newNodeI(nkEffectList, info)
@@ -56,14 +56,15 @@ proc searchObjCaseImpl(obj: PNode; field: PSym): PNode =
     if obj.kind == nkRecCase and obj[0].kind == nkSym and obj[0].sym == field:
       result = obj
     else:
+      result = nil
       for x in obj:
         result = searchObjCaseImpl(x, field)
         if result != nil: break
 
 proc searchObjCase(t: PType; field: PSym): PNode =
   result = searchObjCaseImpl(t.n, field)
-  if result == nil and t.len > 0:
-    result = searchObjCase(t[0].skipTypes({tyAlias, tyGenericInst, tyRef, tyPtr}), field)
+  if result == nil and t.baseClass != nil:
+    result = searchObjCase(t.baseClass.skipTypes({tyAlias, tyGenericInst, tyRef, tyPtr}), field)
   doAssert result != nil
 
 proc genCaseObjDiscMapping*(t: PType; field: PSym; info: TLineInfo; g: ModuleGraph; idgen: IdGenerator): PSym =
@@ -75,7 +76,7 @@ proc genCaseObjDiscMapping*(t: PType; field: PSym; info: TLineInfo; g: ModuleGra
   let res = newSym(skResult, getIdent(g.cache, "result"), idgen, result, info)
   res.typ = getSysType(g, info, tyUInt8)
 
-  result.typ = newType(tyProc, nextTypeId idgen, t.owner)
+  result.typ = newType(tyProc, idgen, t.owner)
   result.typ.n = newNodeI(nkFormalParams, info)
   rawAddSon(result.typ, res.typ)
   result.typ.n.add newNodeI(nkEffectList, info)

compiler/errorhandling.nim

@@ -10,7 +10,8 @@
 ## This module contains support code for new-styled error
 ## handling via an `nkError` node kind.
 
-import ast, renderer, options, strutils, types
+import ast, renderer, options, types
+import std/strutils
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
@@ -40,7 +41,8 @@ proc newError*(wrongNode: PNode; k: ErrorKind; args: varargs[PNode]): PNode =
   let innerError = errorSubNode(wrongNode)
   if innerError != nil:
     return innerError
-  result = newNodeIT(nkError, wrongNode.info, newType(tyError, ItemId(module: -1, item: -1), nil))
+  var idgen = idGeneratorForPackage(-1'i32)
+  result = newNodeIT(nkError, wrongNode.info, newType(tyError, idgen, nil))
   result.add wrongNode
   result.add newIntNode(nkIntLit, ord(k))
   for a in args: result.add a
@@ -50,7 +52,8 @@ proc newError*(wrongNode: PNode; msg: string): PNode =
   let innerError = errorSubNode(wrongNode)
   if innerError != nil:
     return innerError
-  result = newNodeIT(nkError, wrongNode.info, newType(tyError, ItemId(module: -1, item: -1), nil))
+  var idgen = idGeneratorForPackage(-1'i32)
+  result = newNodeIT(nkError, wrongNode.info, newType(tyError, idgen, nil))
   result.add wrongNode
   result.add newIntNode(nkIntLit, ord(CustomError))
   result.add newStrNode(msg, wrongNode.info)

compiler/evalffi.nim

@@ -9,9 +9,11 @@
 
 ## This file implements the FFI part of the evaluator for Nim code.
 
-import ast, types, options, tables, dynlib, msgs, lineinfos
-from os import getAppFilename
-import pkg/libffi
+import ast, types, options, msgs, lineinfos
+from std/os import getAppFilename
+import libffi/libffi
+
+import std/[tables, dynlib]
 
 when defined(windows):
   const libcDll = "msvcrt.dll"
@@ -37,9 +39,10 @@ else:
   var gExeHandle = loadLib()
 
 proc getDll(conf: ConfigRef, cache: var TDllCache; dll: string; info: TLineInfo): pointer =
+  result = nil
   if dll in cache:
     return cache[dll]
-  var libs: seq[string]
+  var libs: seq[string] = @[]
   libCandidates(dll, libs)
   for c in libs:
     result = loadLib(c)
@@ -61,7 +64,7 @@ proc importcSymbol*(conf: ConfigRef, sym: PSym): PNode =
     let lib = sym.annex
     if lib != nil and lib.path.kind notin {nkStrLit..nkTripleStrLit}:
       globalError(conf, sym.info, "dynlib needs to be a string lit")
-    var theAddr: pointer
+    var theAddr: pointer = nil
     if (lib.isNil or lib.kind == libHeader) and not gExeHandle.isNil:
       libPathMsg = "current exe: " & getAppFilename() & " nor libc: " & libcDll
       # first try this exe itself:
@@ -96,7 +99,7 @@ proc mapType(conf: ConfigRef, t: ast.PType): ptr libffi.Type =
      tyTyped, tyTypeDesc, tyProc, tyArray, tyStatic, tyNil:
     result = addr libffi.type_pointer
   of tyDistinct, tyAlias, tySink:
-    result = mapType(conf, t[0])
+    result = mapType(conf, t.skipModifier)
   else:
     result = nil
   # too risky:
@@ -108,6 +111,7 @@ proc mapCallConv(conf: ConfigRef, cc: TCallingConvention, info: TLineInfo): TABI
   of ccStdCall: result = when defined(windows) and defined(x86): STDCALL else: DEFAULT_ABI
   of ccCDecl: result = DEFAULT_ABI
   else:
+    result = default(TABI)
     globalError(conf, info, "cannot map calling convention to FFI")
 
 template rd(typ, p: untyped): untyped = (cast[ptr typ](p))[]
@@ -122,16 +126,18 @@ proc packSize(conf: ConfigRef, v: PNode, typ: PType): int =
     if v.kind in {nkNilLit, nkPtrLit}:
       result = sizeof(pointer)
     else:
-      result = sizeof(pointer) + packSize(conf, v[0], typ.lastSon)
+      result = sizeof(pointer) + packSize(conf, v[0], typ.elementType)
   of tyDistinct, tyGenericInst, tyAlias, tySink:
-    result = packSize(conf, v, typ[0])
+    result = packSize(conf, v, typ.skipModifier)
   of tyArray:
     # consider: ptr array[0..1000_000, int] which is common for interfacing;
     # we use the real length here instead
     if v.kind in {nkNilLit, nkPtrLit}:
       result = sizeof(pointer)
     elif v.len != 0:
-      result = v.len * packSize(conf, v[0], typ[1])
+      result = v.len * packSize(conf, v[0], typ.elementType)
+    else:
+      result = 0
   else:
     result = getSize(conf, typ).int
 
@@ -140,6 +146,7 @@ proc pack(conf: ConfigRef, v: PNode, typ: PType, res: pointer)
 proc getField(conf: ConfigRef, n: PNode; position: int): PSym =
   case n.kind
   of nkRecList:
+    result = nil
     for i in 0..<n.len:
       result = getField(conf, n[i], position)
       if result != nil: return
@@ -154,7 +161,8 @@ proc getField(conf: ConfigRef, n: PNode; position: int): PSym =
       else: internalError(conf, n.info, "getField(record case branch)")
   of nkSym:
     if n.sym.position == position: result = n.sym
-  else: discard
+    else: result = nil
+  else: result = nil
 
 proc packObject(conf: ConfigRef, x: PNode, typ: PType, res: pointer) =
   internalAssert conf, x.kind in {nkObjConstr, nkPar, nkTupleConstr}
@@ -226,19 +234,19 @@ proc pack(conf: ConfigRef, v: PNode, typ: PType, res: pointer) =
         packRecCheck = 0
         globalError(conf, v.info, "cannot map value to FFI " & typeToString(v.typ))
       inc packRecCheck
-      pack(conf, v[0], typ.lastSon, res +! sizeof(pointer))
+      pack(conf, v[0], typ.elementType, res +! sizeof(pointer))
       dec packRecCheck
       awr(pointer, res +! sizeof(pointer))
   of tyArray:
-    let baseSize = getSize(conf, typ[1])
+    let baseSize = getSize(conf, typ.elementType)
     for i in 0..<v.len:
-      pack(conf, v[i], typ[1], res +! i * baseSize)
+      pack(conf, v[i], typ.elementType, res +! i * baseSize)
   of tyObject, tyTuple:
     packObject(conf, v, typ, res)
   of tyNil:
     discard
   of tyDistinct, tyGenericInst, tyAlias, tySink:
-    pack(conf, v, typ[0], res)
+    pack(conf, v, typ.skipModifier, res)
   else:
     globalError(conf, v.info, "cannot map value to FFI " & typeToString(v.typ))
 
@@ -267,7 +275,7 @@ proc unpackObject(conf: ConfigRef, x: pointer, typ: PType, n: PNode): PNode =
   # the nkPar node:
   if n.isNil:
     result = newNode(nkTupleConstr)
-    result.typ = typ
+    result.typ() = typ
     if typ.n.isNil:
       internalError(conf, "cannot unpack unnamed tuple")
     unpackObjectAdd(conf, x, typ.n, result)
@@ -290,15 +298,15 @@ proc unpackObject(conf: ConfigRef, x: pointer, typ: PType, n: PNode): PNode =
 proc unpackArray(conf: ConfigRef, x: pointer, typ: PType, n: PNode): PNode =
   if n.isNil:
     result = newNode(nkBracket)
-    result.typ = typ
+    result.typ() = typ
     newSeq(result.sons, lengthOrd(conf, typ).toInt)
   else:
     result = n
     if result.kind != nkBracket:
       globalError(conf, n.info, "cannot map value from FFI")
-  let baseSize = getSize(conf, typ[1])
+  let baseSize = getSize(conf, typ.elementType)
   for i in 0..<result.len:
-    result[i] = unpack(conf, x +! i * baseSize, typ[1], result[i])
+    result[i] = unpack(conf, x +! i * baseSize, typ.elementType, result[i])
 
 proc canonNodeKind(k: TNodeKind): TNodeKind =
   case k
@@ -311,7 +319,7 @@ proc unpack(conf: ConfigRef, x: pointer, typ: PType, n: PNode): PNode =
   template aw(k, v, field: untyped): untyped =
     if n.isNil:
       result = newNode(k)
-      result.typ = typ
+      result.typ() = typ
     else:
       # check we have the right field:
       result = n
@@ -325,12 +333,12 @@ proc unpack(conf: ConfigRef, x: pointer, typ: PType, n: PNode): PNode =
   template setNil() =
     if n.isNil:
       result = newNode(nkNilLit)
-      result.typ = typ
+      result.typ() = typ
     else:
       reset n[]
       result = n
       result[] = TNode(kind: nkNilLit)
-      result.typ = typ
+      result.typ() = typ
 
   template awi(kind, v: untyped): untyped = aw(kind, v, intVal)
   template awf(kind, v: untyped): untyped = aw(kind, v, floatVal)
@@ -356,6 +364,7 @@ proc unpack(conf: ConfigRef, x: pointer, typ: PType, n: PNode): PNode =
     of 4: awi(nkIntLit, rd(int32, x).BiggestInt)
     of 8: awi(nkIntLit, rd(int64, x).BiggestInt)
     else:
+      result = nil
       globalError(conf, n.info, "cannot map value from FFI (tyEnum, tySet)")
   of tyFloat: awf(nkFloatLit, rd(float, x))
   of tyFloat32: awf(nkFloat32Lit, rd(float32, x))
@@ -378,9 +387,10 @@ proc unpack(conf: ConfigRef, x: pointer, typ: PType, n: PNode): PNode =
       awi(nkPtrLit, cast[int](p))
     elif n != nil and n.len == 1:
       internalAssert(conf, n.kind == nkRefTy)
-      n[0] = unpack(conf, p, typ.lastSon, n[0])
+      n[0] = unpack(conf, p, typ.elementType, n[0])
       result = n
     else:
+      result = nil
       globalError(conf, n.info, "cannot map value from FFI " & typeToString(typ))
   of tyObject, tyTuple:
     result = unpackObject(conf, x, typ, n)
@@ -395,9 +405,10 @@ proc unpack(conf: ConfigRef, x: pointer, typ: PType, n: PNode): PNode =
   of tyNil:
     setNil()
   of tyDistinct, tyGenericInst, tyAlias, tySink:
-    result = unpack(conf, x, typ.lastSon, n)
+    result = unpack(conf, x, typ.skipModifier, n)
   else:
     # XXX what to do with 'array' here?
+    result = nil
     globalError(conf, n.info, "cannot map value from FFI " & typeToString(typ))
 
 proc fficast*(conf: ConfigRef, x: PNode, destTyp: PType): PNode =
@@ -416,15 +427,15 @@ proc fficast*(conf: ConfigRef, x: PNode, destTyp: PType): PNode =
     # cast through a pointer needs a new inner object:
     let y = if x.kind == nkRefTy: newNodeI(nkRefTy, x.info, 1)
             else: x.copyTree
-    y.typ = x.typ
+    y.typ() = x.typ
     result = unpack(conf, a, destTyp, y)
     dealloc a
 
 proc callForeignFunction*(conf: ConfigRef, call: PNode): PNode =
   internalAssert conf, call[0].kind == nkPtrLit
 
-  var cif: TCif
-  var sig: ParamList
+  var cif: TCif = default(TCif)
+  var sig: ParamList = default(ParamList)
   # use the arguments' types for varargs support:
   for i in 1..<call.len:
     sig[i-1] = mapType(conf, call[i].typ)
@@ -433,24 +444,24 @@ proc callForeignFunction*(conf: ConfigRef, call: PNode): PNode =
 
   let typ = call[0].typ
   if prep_cif(cif, mapCallConv(conf, typ.callConv, call.info), cuint(call.len-1),
-              mapType(conf, typ[0]), sig) != OK:
+              mapType(conf, typ.returnType), sig) != OK:
     globalError(conf, call.info, "error in FFI call")
 
-  var args: ArgList
+  var args: ArgList = default(ArgList)
   let fn = cast[pointer](call[0].intVal)
   for i in 1..<call.len:
     var t = call[i].typ
     args[i-1] = alloc0(packSize(conf, call[i], t))
     pack(conf, call[i], t, args[i-1])
-  let retVal = if isEmptyType(typ[0]): pointer(nil)
-               else: alloc(getSize(conf, typ[0]).int)
+  let retVal = if isEmptyType(typ.returnType): pointer(nil)
+               else: alloc(getSize(conf, typ.returnType).int)
 
   libffi.call(cif, fn, retVal, args)
 
   if retVal.isNil:
     result = newNode(nkEmpty)
   else:
-    result = unpack(conf, retVal, typ[0], nil)
+    result = unpack(conf, retVal, typ.returnType, nil)
     result.info = call.info
 
   if retVal != nil: dealloc retVal
@@ -463,14 +474,14 @@ proc callForeignFunction*(conf: ConfigRef, fn: PNode, fntyp: PType,
                           info: TLineInfo): PNode =
   internalAssert conf, fn.kind == nkPtrLit
 
-  var cif: TCif
-  var sig: ParamList
+  var cif: TCif = default(TCif)
+  var sig: ParamList = default(ParamList)
   for i in 0..len-1:
     var aTyp = args[i+start].typ
     if aTyp.isNil:
       internalAssert conf, i+1 < fntyp.len
       aTyp = fntyp[i+1]
-      args[i+start].typ = aTyp
+      args[i+start].typ() = aTyp
     sig[i] = mapType(conf, aTyp)
     if sig[i].isNil: globalError(conf, info, "cannot map FFI type")
 
@@ -478,7 +489,7 @@ proc callForeignFunction*(conf: ConfigRef, fn: PNode, fntyp: PType,
               mapType(conf, fntyp[0]), sig) != OK:
     globalError(conf, info, "error in FFI call")
 
-  var cargs: ArgList
+  var cargs: ArgList = default(ArgList)
   let fn = cast[pointer](fn.intVal)
   for i in 0..len-1:
     let t = args[i+start].typ

compiler/evaltempl.nim

@@ -9,16 +9,16 @@
 
 ## Template evaluation engine. Now hygienic.
 
-import
-  strutils, options, ast, astalgo, msgs, renderer, lineinfos, idents, trees
+import options, ast, astalgo, msgs, renderer, lineinfos, idents, trees
+import std/strutils
 
 type
   TemplCtx = object
     owner, genSymOwner: PSym
     instLines: bool   # use the instantiation lines numbers
     isDeclarative: bool
-    mapping: TIdTable # every gensym'ed symbol needs to be mapped to some
-                      # new symbol
+    mapping: SymMapping # every gensym'ed symbol needs to be mapped to some
+                        # new symbol
     config: ConfigRef
     ic: IdentCache
     instID: int
@@ -33,6 +33,19 @@ proc evalTemplateAux(templ, actual: PNode, c: var TemplCtx, result: PNode) =
     let x = param
     if x.kind == nkArgList:
       for y in items(x): result.add(y)
+    elif nfDefaultRefsParam in x.flags:
+      # value of default param needs to be evaluated like template body
+      # if it contains other template params
+      var res: PNode
+      if isAtom(x):
+        res = newNodeI(nkPar, x.info)
+        evalTemplateAux(x, actual, c, res)
+        if res.len == 1: res = res[0]
+      else:
+        res = copyNode(x)
+        for i in 0..<x.safeLen:
+          evalTemplateAux(x[i], actual, c, res)
+      result.add res
     else:
       result.add copyTree(x)
 
@@ -44,18 +57,19 @@ proc evalTemplateAux(templ, actual: PNode, c: var TemplCtx, result: PNode) =
         handleParam actual[s.position]
       elif (s.owner != nil) and (s.kind == skGenericParam or
            s.kind == skType and s.typ != nil and s.typ.kind == tyGenericParam):
-        handleParam actual[s.owner.typ.len + s.position - 1]
+        handleParam actual[s.owner.typ.signatureLen + s.position - 1]
       else:
         internalAssert c.config, sfGenSym in s.flags or s.kind == skType
-        var x = PSym(idTableGet(c.mapping, s))
+        var x = idTableGet(c.mapping, s)
         if x == nil:
           x = copySym(s, c.idgen)
           # sem'check needs to set the owner properly later, see bug #9476
-          x.owner = nil # c.genSymOwner
+          setOwner(x, nil) # c.genSymOwner
           #if x.kind == skParam and x.owner.kind == skModule:
           #  internalAssert c.config, false
           idTablePut(c.mapping, s, x)
         if sfGenSym in s.flags:
+          # TODO: getIdent(c.ic, "`" & x.name.s & "`gensym" & $c.instID)
           result.add newIdentNode(getIdent(c.ic, x.name.s & "`gensym" & $c.instID),
             if c.instLines: actual.info else: templ.info)
         else:
@@ -116,7 +130,7 @@ proc evalTemplateArgs(n: PNode, s: PSym; conf: ConfigRef; fromHlo: bool): PNode
     # now that we have working untyped parameters.
     genericParams = if fromHlo: 0
                     else: s.ast[genericParamsPos].len
-    expectedRegularParams = s.typ.len-1
+    expectedRegularParams = s.typ.paramsLen
     givenRegularParams = totalParams - genericParams
   if givenRegularParams < 0: givenRegularParams = 0
 
@@ -168,7 +182,7 @@ proc wrapInComesFrom*(info: TLineInfo; sym: PSym; res: PNode): PNode =
     d.add newSymNode(sym, info)
     result.add d
     result.add res
-    result.typ = res.typ
+    result.typ() = res.typ
 
 proc evalTemplate*(n: PNode, tmpl, genSymOwner: PSym;
                    conf: ConfigRef;
@@ -182,14 +196,14 @@ proc evalTemplate*(n: PNode, tmpl, genSymOwner: PSym;
 
   # replace each param by the corresponding node:
   var args = evalTemplateArgs(n, tmpl, conf, fromHlo)
-  var ctx: TemplCtx
-  ctx.owner = tmpl
-  ctx.genSymOwner = genSymOwner
-  ctx.config = conf
-  ctx.ic = ic
-  initIdTable(ctx.mapping)
-  ctx.instID = instID[]
-  ctx.idgen = idgen
+  var ctx = TemplCtx(owner: tmpl,
+    genSymOwner: genSymOwner,
+    config: conf,
+    ic: ic,
+    mapping: initSymMapping(),
+    instID: instID[],
+    idgen: idgen
+  )
 
   let body = tmpl.ast[bodyPos]
   #echo "instantion of ", renderTree(body, {renderIds})

compiler/expanddefaults.nim

@@ -0,0 +1,131 @@
+#
+#
+#           The Nim Compiler
+#        (c) Copyright 2023 Andreas Rumpf
+#
+#    See the file "copying.txt", included in this
+#    distribution, for details about the copyright.
+#
+
+import lineinfos, ast, types
+
+proc caseObjDefaultBranch*(obj: PNode; branch: Int128): int =
+  result = 0
+  for i in 1 ..< obj.len:
+    for j in 0 .. obj[i].len - 2:
+      if obj[i][j].kind == nkRange:
+        let x = getOrdValue(obj[i][j][0])
+        let y = getOrdValue(obj[i][j][1])
+        if branch >= x and branch <= y:
+          return i
+      elif getOrdValue(obj[i][j]) == branch:
+        return i
+    if obj[i].len == 1:
+      # else branch
+      return i
+  return 1
+
+template newZero(t: PType; info: TLineInfo; k = nkIntLit): PNode = newNodeIT(k, info, t)
+
+proc expandDefault*(t: PType; info: TLineInfo): PNode
+
+proc expandField(s: PSym; info: TLineInfo): PNode =
+  result = newNodeIT(nkExprColonExpr, info, s.typ)
+  result.add newSymNode(s)
+  result.add expandDefault(s.typ, info)
+
+proc expandDefaultN(n: PNode; info: TLineInfo; res: PNode) =
+  case n.kind
+  of nkRecList:
+    for i in 0..<n.len:
+      expandDefaultN(n[i], info, res)
+  of nkRecCase:
+    res.add expandField(n[0].sym, info)
+    var branch = Zero
+    let constOrNil = n[0].sym.astdef
+    if constOrNil != nil:
+      branch = getOrdValue(constOrNil)
+
+    let selectedBranch = caseObjDefaultBranch(n, branch)
+    let b = lastSon(n[selectedBranch])
+    expandDefaultN b, info, res
+  of nkSym:
+    res.add expandField(n.sym, info)
+  else:
+    discard
+
+proc expandDefaultObj(t: PType; info: TLineInfo; res: PNode) =
+  if t.baseClass != nil:
+    expandDefaultObj(t.baseClass, info, res)
+  expandDefaultN(t.n, info, res)
+
+proc expandDefault(t: PType; info: TLineInfo): PNode =
+  case t.kind
+  of tyInt:     result = newZero(t, info, nkIntLit)
+  of tyInt8:    result = newZero(t, info, nkInt8Lit)
+  of tyInt16:   result = newZero(t, info, nkInt16Lit)
+  of tyInt32:   result = newZero(t, info, nkInt32Lit)
+  of tyInt64:   result = newZero(t, info, nkInt64Lit)
+  of tyUInt:    result = newZero(t, info, nkUIntLit)
+  of tyUInt8:   result = newZero(t, info, nkUInt8Lit)
+  of tyUInt16:  result = newZero(t, info, nkUInt16Lit)
+  of tyUInt32:  result = newZero(t, info, nkUInt32Lit)
+  of tyUInt64:  result = newZero(t, info, nkUInt64Lit)
+  of tyFloat:   result = newZero(t, info, nkFloatLit)
+  of tyFloat32: result = newZero(t, info, nkFloat32Lit)
+  of tyFloat64: result = newZero(t, info, nkFloat64Lit)
+  of tyFloat128: result = newZero(t, info, nkFloat64Lit)
+  of tyChar:    result = newZero(t, info, nkCharLit)
+  of tyBool:    result = newZero(t, info, nkIntLit)
+  of tyEnum:
+    # Could use low(T) here to finally fix old language quirks
+    result = newZero(t, info, nkIntLit)
+  of tyRange:
+    # Could use low(T) here to finally fix old language quirks
+    result = expandDefault(skipModifier t, info)
+  of tyVoid: result = newZero(t, info, nkEmpty)
+  of tySink, tyGenericInst, tyDistinct, tyAlias, tyOwned:
+    result = expandDefault(t.skipModifier, info)
+  of tyOrdinal, tyGenericBody, tyGenericParam, tyInferred, tyStatic:
+    if t.hasElementType:
+      result = expandDefault(t.skipModifier, info)
+    else:
+      result = newZero(t, info, nkEmpty)
+  of tyFromExpr:
+    if t.n != nil and t.n.typ != nil:
+      result = expandDefault(t.n.typ, info)
+    else:
+      result = newZero(t, info, nkEmpty)
+  of tyArray:
+    result = newZero(t, info, nkBracket)
+    let n = toInt64(lengthOrd(nil, t))
+    for i in 0..<n:
+      result.add expandDefault(t.elementType, info)
+  of tyPtr, tyRef, tyProc, tyPointer, tyCstring:
+    result = newZero(t, info, nkNilLit)
+  of tyVar, tyLent:
+    let e = t.elementType
+    if e.skipTypes(abstractInst).kind in {tyOpenArray, tyVarargs}:
+      # skip the modifier, `var openArray` is a (ptr, len) pair too:
+      result = expandDefault(e, info)
+    else:
+      result = newZero(e, info, nkNilLit)
+  of tySet:
+    result = newZero(t, info, nkCurly)
+  of tyObject:
+    result = newNodeIT(nkObjConstr, info, t)
+    result.add newNodeIT(nkType, info, t)
+    expandDefaultObj(t, info, result)
+  of tyTuple:
+    result = newZero(t, info, nkTupleConstr)
+    for it in t.kids:
+      result.add expandDefault(it, info)
+  of tyVarargs, tyOpenArray, tySequence, tyUncheckedArray:
+    result = newZero(t, info, nkBracket)
+  of tyString:
+    result = newZero(t, info, nkStrLit)
+  of tyNone, tyEmpty, tyUntyped, tyTyped, tyTypeDesc,
+     tyNil, tyGenericInvocation, tyError, tyBuiltInTypeClass,
+     tyUserTypeClass, tyUserTypeClassInst, tyCompositeTypeClass,
+     tyAnd, tyOr, tyNot, tyAnything, tyConcept, tyIterable, tyForward:
+    result = newZero(t, info, nkEmpty) # bug indicator

compiler/extccomp.nim

@@ -63,7 +63,7 @@ type
 
 # Configuration settings for various compilers.
 # When adding new compilers, the cmake sources could be a good reference:
-# http://cmake.org/gitweb?p=cmake.git;a=tree;f=Modules/Platform;
+# https://cmake.org/gitweb?p=cmake.git;a=tree;f=Modules/Platform;
 
 template compiler(name, settings: untyped): untyped =
   proc name: TInfoCC {.compileTime.} = settings
@@ -162,7 +162,11 @@ compiler vcc:
     linkerExe: "cl",
     linkTmpl: "$builddll$vccplatform /Fe$exefile $objfiles $buildgui /nologo $options",
     includeCmd: " /I",
-    linkDirCmd: " /LIBPATH:",
+    # HACK: we call `cl` so we have to pass `/link` for linker options,
+    # but users may still want to pass arguments to `cl` (see #14221)
+    # to deal with this, we add `/link` before each `/LIBPATH`,
+    # the linker ignores extra `/link`s since it's an unrecognized argument
+    linkDirCmd: " /link /LIBPATH:",
     linkLibCmd: " $1.lib",
     debug: " /RTC1 /Z7 ",
     pic: "",
@@ -172,6 +176,22 @@ compiler vcc:
     cppXsupport: "",
     props: {hasCpp, hasAssume, hasDeclspec})
 
+# Nvidia CUDA NVCC Compiler
+compiler nvcc:
+  result = gcc()
+  result.name = "nvcc"
+  result.compilerExe = "nvcc"
+  result.cppCompiler = "nvcc"
+  result.compileTmpl = "-c -x cu -Xcompiler=\"$options\" $include -o $objfile $file"
+  result.linkTmpl = "$buildgui $builddll -o $exefile $objfiles -Xcompiler=\"$options\""
+
+# AMD HIPCC Compiler (rocm/cuda)
+compiler hipcc:
+  result = clang()
+  result.name = "hipcc"
+  result.compilerExe = "hipcc"
+  result.cppCompiler = "hipcc"
+
 compiler clangcl:
   result = vcc()
   result.name = "clang_cl"
@@ -285,7 +305,9 @@ const
     envcc(),
     icl(),
     icc(),
-    clangcl()]
+    clangcl(),
+    hipcc(),
+    nvcc()]
 
   hExt* = ".h"
 
@@ -487,6 +509,10 @@ proc vccplatform(conf: ConfigRef): string =
         of cpuArm: " --platform:arm"
         of cpuAmd64: " --platform:amd64"
         else: ""
+    else:
+      result = ""
+  else:
+    result = ""
 
 proc getLinkOptions(conf: ConfigRef): string =
   result = conf.linkOptions & " " & conf.linkOptionsCmd & " "
@@ -535,7 +561,7 @@ proc ccHasSaneOverflow*(conf: ConfigRef): bool =
     # NOTE: should we need the full version, use -dumpfullversion
     let (s, exitCode) = try: execCmdEx(exe & " -dumpversion") except IOError, OSError, ValueError: ("", 1)
     if exitCode == 0:
-      var major: int
+      var major: int = 0
       discard parseInt(s, major)
       result = major >= 5
   else:
@@ -645,7 +671,7 @@ proc externalFileChanged(conf: ConfigRef; cfile: Cfile): bool =
 
   let hashFile = toGeneratedFile(conf, conf.mangleModuleName(cfile.cname).AbsoluteFile, "sha1")
   let currentHash = footprint(conf, cfile)
-  var f: File
+  var f: File = default(File)
   if open(f, hashFile.string, fmRead):
     let oldHash = parseSecureHash(f.readLine())
     close(f)
@@ -755,7 +781,7 @@ proc getLinkCmd(conf: ConfigRef; output: AbsoluteFile,
     # https://blog.molecular-matters.com/2017/05/09/deleting-pdb-files-locked-by-visual-studio/
     # and a bit about the .pdb format in case that is ever needed:
     # https://github.com/crosire/blink
-    # http://www.debuginfo.com/articles/debuginfomatch.html#pdbfiles
+    # https://www.debuginfo.com/articles/debuginfomatch.html#pdbfiles
     if conf.hcrOn and isVSCompatible(conf):
       let t = now()
       let pdb = output.string & "." & format(t, "MMMM-yyyy-HH-mm-") & $t.nanosecond & ".pdb"
@@ -780,6 +806,7 @@ template tryExceptOSErrorMessage(conf: ConfigRef; errorPrefix: string = "", body
     raise
 
 proc getExtraCmds(conf: ConfigRef; output: AbsoluteFile): seq[string] =
+  result = @[]
   when defined(macosx):
     if optCDebug in conf.globalOptions and optGenStaticLib notin conf.globalOptions:
       # if needed, add an option to skip or override location
@@ -862,6 +889,7 @@ proc hcrLinkTargetName(conf: ConfigRef, objFile: string, isMain = false): Absolu
   result = conf.getNimcacheDir / RelativeFile(targetName)
 
 proc displayProgressCC(conf: ConfigRef, path, compileCmd: string): string =
+  result = ""
   if conf.hasHint(hintCC):
     if optListCmd in conf.globalOptions or conf.verbosity > 1:
       result = MsgKindToStr[hintCC] % (demangleModuleName(path.splitFile.name) & ": " & compileCmd)
@@ -884,15 +912,15 @@ proc preventLinkCmdMaxCmdLen(conf: ConfigRef, linkCmd: string) =
 
 proc callCCompiler*(conf: ConfigRef) =
   var
-    linkCmd: string
+    linkCmd: string = ""
     extraCmds: seq[string]
   if conf.globalOptions * {optCompileOnly, optGenScript} == {optCompileOnly}:
     return # speed up that call if only compiling and no script shall be
            # generated
   #var c = cCompiler
   var script: Rope = ""
-  var cmds: TStringSeq
-  var prettyCmds: TStringSeq
+  var cmds: TStringSeq = default(TStringSeq)
+  var prettyCmds: TStringSeq = default(TStringSeq)
   let prettyCb = proc (idx: int) = writePrettyCmdsStderr(prettyCmds[idx])
 
   for idx, it in conf.toCompile:
@@ -976,10 +1004,11 @@ proc jsonBuildInstructionsFile*(conf: ConfigRef): AbsoluteFile =
   # works out of the box with `hashMainCompilationParams`.
   result = getNimcacheDir(conf) / conf.outFile.changeFileExt("json")
 
-const cacheVersion = "D20210525T193831" # update when `BuildCache` spec changes
+const cacheVersion = "D20240927T193831" # update when `BuildCache` spec changes
 type BuildCache = object
   cacheVersion: string
   outputFile: string
+  outputLastModificationTime: string
   compile: seq[(string, string)]
   link: seq[string]
   linkcmd: string
@@ -1023,12 +1052,15 @@ proc writeJsonBuildInstructions*(conf: ConfigRef; deps: StringTableRef) =
           bcache.depfiles.add (path, $secureHashFile(path))
 
     bcache.nimexe = hashNimExe()
+    if fileExists(bcache.outputFile):
+      bcache.outputLastModificationTime = $getLastModificationTime(bcache.outputFile)
   conf.jsonBuildFile = conf.jsonBuildInstructionsFile
   conf.jsonBuildFile.string.writeFile(bcache.toJson.pretty)
 
 proc changeDetectedViaJsonBuildInstructions*(conf: ConfigRef; jsonFile: AbsoluteFile): bool =
+  result = false
   if not fileExists(jsonFile) or not fileExists(conf.absOutFile): return true
-  var bcache: BuildCache
+  var bcache: BuildCache = default(BuildCache)
   try: bcache.fromJson(jsonFile.string.parseFile)
   except IOError, OSError, ValueError:
     stderr.write "Warning: JSON processing failed for: $#\n" % jsonFile.string
@@ -1042,9 +1074,11 @@ proc changeDetectedViaJsonBuildInstructions*(conf: ConfigRef; jsonFile: Absolute
     # xxx optimize by returning false if stdin input was the same
   for (file, hash) in bcache.depfiles:
     if $secureHashFile(file) != hash: return true
+  if bcache.outputLastModificationTime != $getLastModificationTime(bcache.outputFile):
+    return true
 
 proc runJsonBuildInstructions*(conf: ConfigRef; jsonFile: AbsoluteFile) =
-  var bcache: BuildCache
+  var bcache: BuildCache = default(BuildCache)
   try: bcache.fromJson(jsonFile.string.parseFile)
   except ValueError, KeyError, JsonKindError:
     let e = getCurrentException()
@@ -1057,7 +1091,8 @@ proc runJsonBuildInstructions*(conf: ConfigRef; jsonFile: AbsoluteFile) =
     globalError(conf, gCmdLineInfo,
       "jsonscript command outputFile '$1' must match '$2' which was specified during --compileOnly, see \"outputFile\" entry in '$3' " %
       [outputCurrent, output, jsonFile.string])
-  var cmds, prettyCmds: TStringSeq
+  var cmds: TStringSeq = default(TStringSeq)
+  var prettyCmds: TStringSeq = default(TStringSeq)
   let prettyCb = proc (idx: int) = writePrettyCmdsStderr(prettyCmds[idx])
   for (name, cmd) in bcache.compile:
     cmds.add cmd
@@ -1067,6 +1102,7 @@ proc runJsonBuildInstructions*(conf: ConfigRef; jsonFile: AbsoluteFile) =
   for cmd in bcache.extraCmds: execExternalProgram(conf, cmd, hintExecuting)
 
 proc genMappingFiles(conf: ConfigRef; list: CfileList): Rope =
+  result = ""
   for it in list:
     result.addf("--file:r\"$1\"$N", [rope(it.cname.string)])
 

compiler/filter_tmpl.nim

@@ -10,9 +10,11 @@
 # This module implements Nim's standard template filter.
 
 import
-  llstream, strutils, ast, msgs, options,
+  llstream, ast, msgs, options,
   filters, lineinfos, pathutils
 
+import std/strutils
+
 type
   TParseState = enum
     psDirective, psTempl
@@ -201,17 +203,15 @@ proc parseLine(p: var TTmplParser) =
 
 proc filterTmpl*(conf: ConfigRef, stdin: PLLStream, filename: AbsoluteFile,
                  call: PNode): PLLStream =
-  var p: TTmplParser
-  p.config = conf
-  p.info = newLineInfo(conf, filename, 0, 0)
-  p.outp = llStreamOpen("")
-  p.inp = stdin
-  p.subsChar = charArg(conf, call, "subschar", 1, '$')
-  p.nimDirective = charArg(conf, call, "metachar", 2, '#')
-  p.emit = strArg(conf, call, "emit", 3, "result.add")
-  p.conc = strArg(conf, call, "conc", 4, " & ")
-  p.toStr = strArg(conf, call, "tostring", 5, "$")
-  p.x = newStringOfCap(120)
+  var p = TTmplParser(config: conf, info: newLineInfo(conf, filename, 0, 0),
+                outp: llStreamOpen(""), inp: stdin,
+                subsChar: charArg(conf, call, "subschar", 1, '$'),
+                nimDirective: charArg(conf, call, "metachar", 2, '#'),
+                emit: strArg(conf, call, "emit", 3, "result.add"),
+                conc: strArg(conf, call, "conc", 4, " & "),
+                toStr: strArg(conf, call, "tostring", 5, "$"),
+                x: newStringOfCap(120)
+                )
   # do not process the first line which contains the directive:
   if llStreamReadLine(p.inp, p.x):
     inc p.info.line

compiler/filters.nim

@@ -10,9 +10,11 @@
 # This module implements Nim's simple filters and helpers for filters.
 
 import
-  llstream, idents, strutils, ast, msgs, options,
+  llstream, idents, ast, msgs, options,
   renderer, pathutils
 
+import std/strutils
+
 proc invalidPragma(conf: ConfigRef; n: PNode) =
   localError(conf, n.info,
       "'$1' not allowed here" % renderTree(n, {renderNoComments}))
@@ -29,23 +31,30 @@ proc getArg(conf: ConfigRef; n: PNode, name: string, pos: int): PNode =
       return n[i]
 
 proc charArg*(conf: ConfigRef; n: PNode, name: string, pos: int, default: char): char =
+
   var x = getArg(conf, n, name, pos)
   if x == nil: result = default
   elif x.kind == nkCharLit: result = chr(int(x.intVal))
-  else: invalidPragma(conf, n)
+  else:
+    result = default(char)
+    invalidPragma(conf, n)
 
 proc strArg*(conf: ConfigRef; n: PNode, name: string, pos: int, default: string): string =
   var x = getArg(conf, n, name, pos)
   if x == nil: result = default
   elif x.kind in {nkStrLit..nkTripleStrLit}: result = x.strVal
-  else: invalidPragma(conf, n)
+  else:
+    result = ""
+    invalidPragma(conf, n)
 
 proc boolArg*(conf: ConfigRef; n: PNode, name: string, pos: int, default: bool): bool =
   var x = getArg(conf, n, name, pos)
   if x == nil: result = default
   elif x.kind == nkIdent and cmpIgnoreStyle(x.ident.s, "true") == 0: result = true
   elif x.kind == nkIdent and cmpIgnoreStyle(x.ident.s, "false") == 0: result = false
-  else: invalidPragma(conf, n)
+  else:
+    result = false
+    invalidPragma(conf, n)
 
 proc filterStrip*(conf: ConfigRef; stdin: PLLStream, filename: AbsoluteFile, call: PNode): PLLStream =
   var pattern = strArg(conf, call, "startswith", 1, "")

compiler/gorgeimpl.nim

@@ -9,8 +9,9 @@
 
 ## Module that implements ``gorge`` for the compiler.
 
-import msgs, os, osproc, streams, options,
-  lineinfos, pathutils
+import msgs, options, lineinfos, pathutils
+
+import std/[os, osproc, streams]
 
 when defined(nimPreviewSlimSystem):
   import std/syncio
@@ -29,10 +30,11 @@ proc readOutput(p: Process): (string, int) =
 
 proc opGorge*(cmd, input, cache: string, info: TLineInfo; conf: ConfigRef): (string, int) =
   let workingDir = parentDir(toFullPath(conf, info))
+  result = ("", 0)
   if cache.len > 0:
     let h = secureHash(cmd & "\t" & input & "\t" & cache)
     let filename = toGeneratedFile(conf, AbsoluteFile("gorge_" & $h), "txt").string
-    var f: File
+    var f: File = default(File)
     if optForceFullMake notin conf.globalOptions and open(f, filename):
       result = (f.readAll, 0)
       f.close

compiler/guards.nim

@@ -51,6 +51,10 @@ proc isLet(n: PNode): bool =
     elif n.sym.kind == skParam and skipTypes(n.sym.typ,
                                              abstractInst).kind notin {tyVar}:
       result = true
+    else:
+      result = false
+  else:
+    result = false
 
 proc isVar(n: PNode): bool =
   n.kind == nkSym and n.sym.kind in {skResult, skVar} and
@@ -136,6 +140,8 @@ proc neg(n: PNode; o: Operators): PNode =
       result = a
     elif b != nil:
       result = b
+    else:
+      result = nil
   else:
     # leave  not (a == 4)  as it is
     result = newNodeI(nkCall, n.info, 2)
@@ -330,6 +336,8 @@ proc usefulFact(n: PNode; o: Operators): PNode =
         result = n
       elif n[1].getMagic in someLen or n[2].getMagic in someLen:
         result = n
+      else:
+        result = nil
   of someLe+someLt:
     if isLetLocation(n[1], true) or isLetLocation(n[2], true):
       # XXX algebraic simplifications!  'i-1 < a.len' --> 'i < a.len+1'
@@ -337,12 +345,18 @@ proc usefulFact(n: PNode; o: Operators): PNode =
     elif n[1].getMagic in someLen or n[2].getMagic in someLen:
       # XXX Rethink this whole idea of 'usefulFact' for semparallel
       result = n
+    else:
+      result = nil
   of mIsNil:
     if isLetLocation(n[1], false) or isVar(n[1]):
       result = n
+    else:
+      result = nil
   of someIn:
     if isLetLocation(n[1], true):
       result = n
+    else:
+      result = nil
   of mAnd:
     let
       a = usefulFact(n[1], o)
@@ -356,10 +370,14 @@ proc usefulFact(n: PNode; o: Operators): PNode =
       result = a
     elif b != nil:
       result = b
+    else:
+      result = nil
   of mNot:
     let a = usefulFact(n[1], o)
     if a != nil:
       result = a.neg(o)
+    else:
+      result = nil
   of mOr:
     # 'or' sucks! (p.isNil or q.isNil) --> hard to do anything
     # with that knowledge...
@@ -376,6 +394,8 @@ proc usefulFact(n: PNode; o: Operators): PNode =
       result[1] = a
       result[2] = b
       result = result.neg(o)
+    else:
+      result = nil
   elif n.kind == nkSym and n.sym.kind == skLet:
     # consider:
     #   let a = 2 < x
@@ -384,8 +404,12 @@ proc usefulFact(n: PNode; o: Operators): PNode =
     # We make can easily replace 'a' by '2 < x' here:
     if n.sym.astdef != nil:
       result = usefulFact(n.sym.astdef, o)
+    else:
+      result = nil
   elif n.kind == nkStmtListExpr:
     result = usefulFact(n.lastSon, o)
+  else:
+    result = nil
 
 type
   TModel* = object
@@ -451,8 +475,9 @@ proc hasSubTree(n, x: PNode): bool =
     of nkEmpty..nkNilLit:
       result = n.sameTree(x)
     of nkFormalParams:
-      discard
+      result = false
     else:
+      result = false
       for i in 0..<n.len:
         if hasSubTree(n[i], x): return true
 
@@ -483,6 +508,8 @@ proc invalidateFacts*(m: var TModel, n: PNode) =
 proc valuesUnequal(a, b: PNode): bool =
   if a.isValue and b.isValue:
     result = not sameValue(a, b)
+  else:
+    result = false
 
 proc impliesEq(fact, eq: PNode): TImplication =
   let (loc, val) = if isLocation(eq[1]): (1, 2) else: (2, 1)
@@ -493,16 +520,26 @@ proc impliesEq(fact, eq: PNode): TImplication =
       # this is not correct; consider:  a == b;  a == 1 --> unknown!
       if sameTree(fact[2], eq[val]): result = impYes
       elif valuesUnequal(fact[2], eq[val]): result = impNo
+      else:
+        result = impUnknown
     elif sameTree(fact[2], eq[loc]):
       if sameTree(fact[1], eq[val]): result = impYes
       elif valuesUnequal(fact[1], eq[val]): result = impNo
+      else:
+        result = impUnknown
+    else:
+      result = impUnknown
   of mInSet:
     # remember: mInSet is 'contains' so the set comes first!
     if sameTree(fact[2], eq[loc]) and isValue(eq[val]):
       if inSet(fact[1], eq[val]): result = impYes
       else: result = impNo
-  of mNot, mOr, mAnd: assert(false, "impliesEq")
-  else: discard
+    else:
+      result = impUnknown
+  of mNot, mOr, mAnd:
+    result = impUnknown
+    assert(false, "impliesEq")
+  else: result = impUnknown
 
 proc leImpliesIn(x, c, aSet: PNode): TImplication =
   if c.kind in {nkCharLit..nkUInt64Lit}:
@@ -512,13 +549,19 @@ proc leImpliesIn(x, c, aSet: PNode): TImplication =
     var value = newIntNode(c.kind, firstOrd(nil, x.typ))
     # don't iterate too often:
     if c.intVal - value.intVal < 1000:
-      var i, pos, neg: int
+      var i, pos, neg: int = 0
       while value.intVal <= c.intVal:
         if inSet(aSet, value): inc pos
         else: inc neg
         inc i; inc value.intVal
       if pos == i: result = impYes
       elif neg == i: result = impNo
+      else:
+        result = impUnknown
+    else:
+      result = impUnknown
+  else:
+    result = impUnknown
 
 proc geImpliesIn(x, c, aSet: PNode): TImplication =
   if c.kind in {nkCharLit..nkUInt64Lit}:
@@ -529,17 +572,23 @@ proc geImpliesIn(x, c, aSet: PNode): TImplication =
     let max = lastOrd(nil, x.typ)
     # don't iterate too often:
     if max - getInt(value) < toInt128(1000):
-      var i, pos, neg: int
+      var i, pos, neg: int = 0
       while value.intVal <= max:
         if inSet(aSet, value): inc pos
         else: inc neg
         inc i; inc value.intVal
       if pos == i: result = impYes
       elif neg == i: result = impNo
+      else: result = impUnknown
+    else:
+      result = impUnknown
+  else:
+    result = impUnknown
 
 proc compareSets(a, b: PNode): TImplication =
   if equalSets(nil, a, b): result = impYes
   elif intersectSets(nil, a, b).len == 0: result = impNo
+  else: result = impUnknown
 
 proc impliesIn(fact, loc, aSet: PNode): TImplication =
   case fact[0].sym.magic
@@ -550,22 +599,32 @@ proc impliesIn(fact, loc, aSet: PNode): TImplication =
     elif sameTree(fact[2], loc):
       if inSet(aSet, fact[1]): result = impYes
       else: result = impNo
+    else:
+      result = impUnknown
   of mInSet:
     if sameTree(fact[2], loc):
       result = compareSets(fact[1], aSet)
+    else:
+      result = impUnknown
   of someLe:
     if sameTree(fact[1], loc):
       result = leImpliesIn(fact[1], fact[2], aSet)
     elif sameTree(fact[2], loc):
       result = geImpliesIn(fact[2], fact[1], aSet)
+    else:
+      result = impUnknown
   of someLt:
     if sameTree(fact[1], loc):
       result = leImpliesIn(fact[1], fact[2].pred, aSet)
     elif sameTree(fact[2], loc):
       # 4 < x  -->  3 <= x
       result = geImpliesIn(fact[2], fact[1].pred, aSet)
-  of mNot, mOr, mAnd: assert(false, "impliesIn")
-  else: discard
+    else:
+      result = impUnknown
+  of mNot, mOr, mAnd:
+    result = impUnknown
+    assert(false, "impliesIn")
+  else: result = impUnknown
 
 proc valueIsNil(n: PNode): TImplication =
   if n.kind == nkNilLit: impYes
@@ -577,13 +636,19 @@ proc impliesIsNil(fact, eq: PNode): TImplication =
   of mIsNil:
     if sameTree(fact[1], eq[1]):
       result = impYes
+    else:
+      result = impUnknown
   of someEq:
     if sameTree(fact[1], eq[1]):
       result = valueIsNil(fact[2].skipConv)
     elif sameTree(fact[2], eq[1]):
       result = valueIsNil(fact[1].skipConv)
-  of mNot, mOr, mAnd: assert(false, "impliesIsNil")
-  else: discard
+    else:
+      result = impUnknown
+  of mNot, mOr, mAnd:
+    result = impUnknown
+    assert(false, "impliesIsNil")
+  else: result = impUnknown
 
 proc impliesGe(fact, x, c: PNode): TImplication =
   assert isLocation(x)
@@ -594,32 +659,57 @@ proc impliesGe(fact, x, c: PNode): TImplication =
         # fact:  x = 4;  question x >= 56? --> true iff 4 >= 56
         if leValue(c, fact[2]): result = impYes
         else: result = impNo
+      else:
+        result = impUnknown
     elif sameTree(fact[2], x):
       if isValue(fact[1]) and isValue(c):
         if leValue(c, fact[1]): result = impYes
         else: result = impNo
+      else:
+        result = impUnknown
+    else:
+      result = impUnknown
   of someLt:
     if sameTree(fact[1], x):
       if isValue(fact[2]) and isValue(c):
         # fact:  x < 4;  question N <= x? --> false iff N <= 4
         if leValue(fact[2], c): result = impNo
+        else: result = impUnknown
         # fact:  x < 4;  question 2 <= x? --> we don't know
+      else:
+        result = impUnknown
     elif sameTree(fact[2], x):
       # fact: 3 < x; question: N-1 < x ?  --> true iff N-1 <= 3
       if isValue(fact[1]) and isValue(c):
         if leValue(c.pred, fact[1]): result = impYes
+        else: result = impUnknown
+      else:
+        result = impUnknown
+    else:
+      result = impUnknown
   of someLe:
     if sameTree(fact[1], x):
       if isValue(fact[2]) and isValue(c):
         # fact:  x <= 4;  question x >= 56? --> false iff 4 <= 56
         if leValue(fact[2], c): result = impNo
         # fact:  x <= 4;  question x >= 2? --> we don't know
+        else:
+          result = impUnknown
+      else:
+        result = impUnknown
     elif sameTree(fact[2], x):
       # fact: 3 <= x; question: x >= 2 ?  --> true iff 2 <= 3
       if isValue(fact[1]) and isValue(c):
         if leValue(c, fact[1]): result = impYes
-  of mNot, mOr, mAnd: assert(false, "impliesGe")
-  else: discard
+        else: result = impUnknown
+      else:
+        result = impUnknown
+    else:
+      result = impUnknown
+  of mNot, mOr, mAnd:
+    result = impUnknown
+    assert(false, "impliesGe")
+  else: result = impUnknown
 
 proc impliesLe(fact, x, c: PNode): TImplication =
   if not isLocation(x):
@@ -634,35 +724,59 @@ proc impliesLe(fact, x, c: PNode): TImplication =
         # fact:  x = 4;  question x <= 56? --> true iff 4 <= 56
         if leValue(fact[2], c): result = impYes
         else: result = impNo
+      else:
+        result = impUnknown
     elif sameTree(fact[2], x):
       if isValue(fact[1]) and isValue(c):
         if leValue(fact[1], c): result = impYes
         else: result = impNo
+      else:
+        result = impUnknown
+    else:
+      result = impUnknown
   of someLt:
     if sameTree(fact[1], x):
       if isValue(fact[2]) and isValue(c):
         # fact:  x < 4;  question x <= N? --> true iff N-1 <= 4
         if leValue(fact[2], c.pred): result = impYes
+        else:
+          result = impUnknown
         # fact:  x < 4;  question x <= 2? --> we don't know
+      else:
+        result = impUnknown
     elif sameTree(fact[2], x):
       # fact: 3 < x; question: x <= 1 ?  --> false iff 1 <= 3
       if isValue(fact[1]) and isValue(c):
         if leValue(c, fact[1]): result = impNo
-
+        else: result = impUnknown
+      else:
+        result = impUnknown
+    else:
+      result = impUnknown
   of someLe:
     if sameTree(fact[1], x):
       if isValue(fact[2]) and isValue(c):
         # fact:  x <= 4;  question x <= 56? --> true iff 4 <= 56
         if leValue(fact[2], c): result = impYes
+        else: result = impUnknown
         # fact:  x <= 4;  question x <= 2? --> we don't know
+      else:
+        result = impUnknown
 
     elif sameTree(fact[2], x):
       # fact: 3 <= x; question: x <= 2 ?  --> false iff 2 < 3
       if isValue(fact[1]) and isValue(c):
         if leValue(c, fact[1].pred): result = impNo
+        else:result = impUnknown
+      else:
+        result = impUnknown
+    else:
+      result = impUnknown
 
-  of mNot, mOr, mAnd: assert(false, "impliesLe")
-  else: discard
+  of mNot, mOr, mAnd:
+    result = impUnknown
+    assert(false, "impliesLe")
+  else: result = impUnknown
 
 proc impliesLt(fact, x, c: PNode): TImplication =
   # x < 3  same as x <= 2:
@@ -674,6 +788,8 @@ proc impliesLt(fact, x, c: PNode): TImplication =
     let q = x.pred
     if q != x:
       result = impliesLe(fact, q, c)
+    else:
+      result = impUnknown
 
 proc `~`(x: TImplication): TImplication =
   case x
@@ -725,6 +841,7 @@ proc factImplies(fact, prop: PNode): TImplication =
 
 proc doesImply*(facts: TModel, prop: PNode): TImplication =
   assert prop.kind in nkCallKinds
+  result = impUnknown
   for f in facts.s:
     # facts can be invalidated, in which case they are 'nil':
     if not f.isNil:
@@ -753,7 +870,7 @@ template isSub(x): untyped = x.getMagic in someSub
 template isVal(x): untyped = x.kind in {nkCharLit..nkUInt64Lit}
 template isIntVal(x, y): untyped = x.intVal == y
 
-import macros
+import std/macros
 
 macro `=~`(x: PNode, pat: untyped): bool =
   proc m(x, pat, conds: NimNode) =
@@ -900,6 +1017,7 @@ proc applyReplacements(n: PNode; rep: TReplacements): PNode =
 
 proc pleViaModelRec(m: var TModel; a, b: PNode): TImplication =
   # now check for inferrable facts: a <= b and b <= c  implies a <= c
+  result = impUnknown
   for i in 0..m.s.high:
     let fact = m.s[i]
     if fact != nil and fact.getMagic in someLe:
@@ -945,7 +1063,7 @@ proc pleViaModel(model: TModel; aa, bb: PNode): TImplication =
       let b = fact[2]
       if a.kind == nkSym: replacements.add((a,b))
       else: replacements.add((b,a))
-  var m: TModel
+  var m = TModel()
   var a = aa
   var b = bb
   if replacements.len > 0:
@@ -980,13 +1098,13 @@ proc addFactLt*(m: var TModel; a, b: PNode) =
   addFactLe(m, a, bb)
 
 proc settype(n: PNode): PType =
-  result = newType(tySet, ItemId(module: -1, item: -1), n.typ.owner)
-  var idgen: IdGenerator
+  var idgen = idGeneratorForPackage(-1'i32)
+  result = newType(tySet, idgen, n.typ.owner)
   addSonSkipIntLit(result, n.typ, idgen)
 
 proc buildOf(it, loc: PNode; o: Operators): PNode =
   var s = newNodeI(nkCurly, it.info, it.len-1)
-  s.typ = settype(loc)
+  s.typ() = settype(loc)
   for i in 0..<it.len-1: s[i] = it[i]
   result = newNodeI(nkCall, it.info, 3)
   result[0] = newSymNode(o.opContains)
@@ -1047,8 +1165,12 @@ proc buildProperFieldCheck(access, check: PNode; o: Operators): PNode =
   if check[1].kind == nkCurly:
     result = copyTree(check)
     if access.kind == nkDotExpr:
+      # change the access to the discriminator field access
       var a = copyTree(access)
+      # set field name to discriminator field name
       a[1] = check[2]
+      # set discriminator field type: important for `neg`
+      a.typ() = check[2].typ
       result[2] = a
       # 'access.kind != nkDotExpr' can happen for object constructors
       # which we don't check yet

compiler/hlo.nim

@@ -17,9 +17,11 @@ proc evalPattern(c: PContext, n, orig: PNode): PNode =
   # we need to ensure that the resulting AST is semchecked. However, it's
   # awful to semcheck before macro invocation, so we don't and treat
   # templates and macros as immediate in this context.
-  var rule: string
-  if c.config.hasHint(hintPattern):
-    rule = renderTree(n, {renderNoComments})
+  var rule: string =
+    if c.config.hasHint(hintPattern):
+      renderTree(n, {renderNoComments})
+    else:
+      ""
   let s = n[0].sym
   case s.kind
   of skMacro:
@@ -70,7 +72,7 @@ proc hlo(c: PContext, n: PNode): PNode =
   else:
     if n.kind in {nkFastAsgn, nkAsgn, nkSinkAsgn, nkIdentDefs, nkVarTuple} and
         n[0].kind == nkSym and
-        {sfGlobal, sfPure} * n[0].sym.flags == {sfGlobal, sfPure}:
+        {sfGlobal, sfPure} <= n[0].sym.flags:
       # do not optimize 'var g {.global} = re(...)' again!
       return n
     result = applyPatterns(c, n)

compiler/ic/bitabs.nim

@@ -1,7 +1,8 @@
 ## A BiTable is a table that can be seen as an optimized pair
 ## of `(Table[LitId, Val], Table[Val, LitId])`.
 
-import hashes, rodfiles
+import std/hashes
+import rodfiles
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
@@ -13,6 +14,8 @@ type
     vals: seq[T] # indexed by LitId
     keys: seq[LitId]  # indexed by hash(val)
 
+proc initBiTable*[T](): BiTable[T] = BiTable[T](vals: @[], keys: @[])
+
 proc nextTry(h, maxHash: Hash): Hash {.inline.} =
   result = (h + 1) and maxHash
 
@@ -33,9 +36,7 @@ proc mustRehash(length, counter: int): bool {.inline.} =
   result = (length * 2 < counter * 3) or (length - counter < 4)
 
 const
-  idStart = 256 ##
-  ## Ids do not start with 0 but with this value. The IR needs it.
-  ## TODO: explain why
+  idStart = 1
 
 template idToIdx(x: LitId): int = x.int - idStart
 
@@ -118,6 +119,12 @@ proc load*[T](f: var RodFile; t: var BiTable[T]) =
   loadSeq(f, t.vals)
   loadSeq(f, t.keys)
 
+proc sizeOnDisc*(t: BiTable[string]): int =
+  result = 4
+  for x in t.vals:
+    result += x.len + 4
+  result += t.keys.len * sizeof(LitId)
+
 when isMainModule:
 
   var t: BiTable[string]

compiler/ic/cbackend.nim

@@ -18,7 +18,7 @@
 ## also doing cross-module dependency tracking and DCE that we don't need
 ## anymore. DCE is now done as prepass over the entire packed module graph.
 
-import std/packedsets, algorithm, tables
+import std/[packedsets, algorithm, tables]
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
@@ -50,10 +50,9 @@ proc generateCodeForModule(g: ModuleGraph; m: var LoadedModule; alive: var Alive
     let n = unpackTree(g, m.module.position, m.fromDisk.topLevel, p)
     cgen.genTopLevelStmt(bmod, n)
 
-  let disps = finalCodegenActions(g, bmod, newNodeI(nkStmtList, m.module.info))
-  if disps != nil:
-    for disp in disps:
-      genProcAux(bmod, disp.sym)
+  finalCodegenActions(g, bmod, newNodeI(nkStmtList, m.module.info))
+  for disp in getDispatchers(g):
+    genProcAux(bmod, disp)
   m.fromDisk.backendFlags = cgen.whichInitProcs(bmod)
 
 proc replayTypeInfo(g: ModuleGraph; m: var LoadedModule; origin: FileIndex) =
@@ -101,7 +100,7 @@ proc aliveSymsChanged(config: ConfigRef; position: int; alive: AliveSyms): bool
   var f2 = rodfiles.open(asymFile.string)
   f2.loadHeader()
   f2.loadSection aliveSymsSection
-  var oldData: seq[int32]
+  var oldData: seq[int32] = @[]
   f2.loadSeq(oldData)
   f2.close
   if f2.err == ok and oldData == s:
@@ -147,12 +146,12 @@ proc generateCode*(g: ModuleGraph) =
   var alive = computeAliveSyms(g.packed, g.config)
 
   when false:
-    for i in 0..high(g.packed):
+    for i in 0..<len(g.packed):
       echo i, " is of status ", g.packed[i].status, " ", toFullPath(g.config, FileIndex(i))
 
   # First pass: Setup all the backend modules for all the modules that have
   # changed:
-  for i in 0..high(g.packed):
+  for i in 0..<len(g.packed):
     # case statement here to enforce exhaustive checks.
     case g.packed[i].status
     of undefined:
@@ -174,7 +173,7 @@ proc generateCode*(g: ModuleGraph) =
   let mainModuleIdx = g.config.projectMainIdx2.int
   # We need to generate the main module last, because only then
   # all init procs have been registered:
-  for i in 0..high(g.packed):
+  for i in 0..<len(g.packed):
     if i != mainModuleIdx:
       genPackedModule(g, i, alive)
   if mainModuleIdx >= 0:

compiler/ic/dce.nim

@@ -40,10 +40,14 @@ proc isExportedToC(c: var AliveContext; g: PackedModuleGraph; symId: int32): boo
     if ({sfExportc, sfCompilerProc} * flags != {}) or
         (symPtr.kind == skMethod):
       result = true
+    else:
+      result = false
       # XXX: This used to be a condition to:
       #  (sfExportc in prc.flags and lfExportLib in prc.loc.flags) or
     if sfCompilerProc in flags:
       c.compilerProcs[g[c.thisModule].fromDisk.strings[symPtr.name]] = (c.thisModule, symId)
+  else:
+    result = false
 
 template isNotGeneric(n: NodePos): bool = ithSon(tree, n, genericParamsPos).kind == nkEmpty
 
@@ -105,13 +109,13 @@ proc aliveCode(c: var AliveContext; g: PackedModuleGraph; tree: PackedTree; n: N
     discard "ignore non-sym atoms"
   of nkSym:
     # This symbol is alive and everything its body references.
-    followLater(c, g, c.thisModule, n.operand)
+    followLater(c, g, c.thisModule, tree[n].soperand)
   of nkModuleRef:
     let (n1, n2) = sons2(tree, n)
-    assert n1.kind == nkInt32Lit
-    assert n2.kind == nkInt32Lit
+    assert n1.kind == nkNone
+    assert n2.kind == nkNone
     let m = n1.litId
-    let item = n2.operand
+    let item = tree[n2].soperand
     let otherModule = toFileIndexCached(c.decoder, g, c.thisModule, m).int
     followLater(c, g, otherModule, item)
   of nkMacroDef, nkTemplateDef, nkTypeSection, nkTypeOfExpr,
@@ -127,7 +131,7 @@ proc aliveCode(c: var AliveContext; g: PackedModuleGraph; tree: PackedTree; n: N
     rangeCheckAnalysis(c, g, tree, n)
   of nkProcDef, nkConverterDef, nkMethodDef, nkFuncDef, nkIteratorDef:
     if n.firstSon.kind == nkSym and isNotGeneric(n):
-      let item = n.firstSon.operand
+      let item = tree[n.firstSon].soperand
       if isExportedToC(c, g, item):
         # This symbol is alive and everything its body references.
         followLater(c, g, c.thisModule, item)
@@ -149,7 +153,7 @@ proc computeAliveSyms*(g: PackedModuleGraph; conf: ConfigRef): AliveSyms =
   var c = AliveContext(stack: @[], decoder: PackedDecoder(config: conf),
                        thisModule: -1, alive: newSeq[IntSet](g.len),
                        options: conf.options)
-  for i in countdown(high(g), 0):
+  for i in countdown(len(g)-1, 0):
     if g[i].status != undefined:
       c.thisModule = i
       for p in allNodes(g[i].fromDisk.topLevel):

compiler/ic/ic.nim

@@ -7,15 +7,17 @@
 #    distribution, for details about the copyright.
 #
 
-import hashes, tables, intsets
+import std/[hashes, tables, intsets, monotimes]
 import packed_ast, bitabs, rodfiles
 import ".." / [ast, idents, lineinfos, msgs, ropes, options,
   pathutils, condsyms, packages, modulepaths]
 #import ".." / [renderer, astalgo]
-from os import removeFile, isAbsolute
+from std/os import removeFile, isAbsolute
 
 import ../../dist/checksums/src/checksums/sha1
 
+import iclineinfos
+
 when defined(nimPreviewSlimSystem):
   import std/[syncio, assertions, formatfloat]
 
@@ -41,25 +43,28 @@ type
     bodies*: PackedTree # other trees. Referenced from typ.n and sym.ast by their position.
     #producedGenerics*: Table[GenericKey, SymId]
     exports*: seq[(LitId, int32)]
-    hidden*: seq[(LitId, int32)]
-    reexports*: seq[(LitId, PackedItemId)]
+    hidden: seq[(LitId, int32)]
+    reexports: seq[(LitId, PackedItemId)]
     compilerProcs*: seq[(LitId, int32)]
     converters*, methods*, trmacros*, pureEnums*: seq[int32]
 
     typeInstCache*: seq[(PackedItemId, PackedItemId)]
     procInstCache*: seq[PackedInstantiation]
     attachedOps*: seq[(PackedItemId, TTypeAttachedOp, PackedItemId)]
-    methodsPerType*: seq[(PackedItemId, int, PackedItemId)]
+    methodsPerGenericType*: seq[(PackedItemId, int, PackedItemId)]
     enumToStringProcs*: seq[(PackedItemId, PackedItemId)]
+    methodsPerType*: seq[(PackedItemId, PackedItemId)]
+    dispatchers*: seq[PackedItemId]
 
     emittedTypeInfo*: seq[string]
     backendFlags*: set[ModuleBackendFlag]
 
-    syms*: seq[PackedSym]
-    types*: seq[PackedType]
+    syms*: OrderedTable[int32, PackedSym]
+    types*: OrderedTable[int32, PackedType]
     strings*: BiTable[string] # we could share these between modules.
     numbers*: BiTable[BiggestInt] # we also store floats in here so
                                   # that we can assure that every bit is kept
+    man*: LineInfoManager
 
     cfg: PackedConfig
 
@@ -75,37 +80,36 @@ type
     symMarker*: IntSet #Table[ItemId, SymId]    # ItemId.item -> SymId
     config*: ConfigRef
 
-proc toString*(tree: PackedTree; n: NodePos; m: PackedModule; nesting: int;
+proc toString*(tree: PackedTree; pos: NodePos; m: PackedModule; nesting: int;
                result: var string) =
-  let pos = n.int
   if result.len > 0 and result[^1] notin {' ', '\n'}:
     result.add ' '
 
   result.add $tree[pos].kind
-  case tree.nodes[pos].kind
-  of nkNone, nkEmpty, nkNilLit, nkType: discard
+  case tree[pos].kind
+  of nkEmpty, nkNilLit, nkType: discard
   of nkIdent, nkStrLit..nkTripleStrLit:
     result.add " "
-    result.add m.strings[LitId tree.nodes[pos].operand]
+    result.add m.strings[LitId tree[pos].uoperand]
   of nkSym:
     result.add " "
-    result.add m.strings[m.syms[tree.nodes[pos].operand].name]
+    result.add m.strings[m.syms[tree[pos].soperand].name]
   of directIntLit:
     result.add " "
-    result.addInt tree.nodes[pos].operand
+    result.addInt tree[pos].soperand
   of externSIntLit:
     result.add " "
-    result.addInt m.numbers[LitId tree.nodes[pos].operand]
+    result.addInt m.numbers[LitId tree[pos].uoperand]
   of externUIntLit:
     result.add " "
-    result.addInt cast[uint64](m.numbers[LitId tree.nodes[pos].operand])
+    result.addInt cast[uint64](m.numbers[LitId tree[pos].uoperand])
   of nkFloatLit..nkFloat128Lit:
     result.add " "
-    result.addFloat cast[BiggestFloat](m.numbers[LitId tree.nodes[pos].operand])
+    result.addFloat cast[BiggestFloat](m.numbers[LitId tree[pos].uoperand])
   else:
     result.add "(\n"
     for i in 1..(nesting+1)*2: result.add ' '
-    for child in sonsReadonly(tree, n):
+    for child in sonsReadonly(tree, pos):
       toString(tree, child, m, nesting + 1, result)
     result.add "\n"
     for i in 1..nesting*2: result.add ' '
@@ -231,10 +235,14 @@ proc addImportFileDep*(c: var PackedEncoder; m: var PackedModule; f: FileIndex)
   m.imports.add toLitId(f, c, m)
 
 proc addHidden*(c: var PackedEncoder; m: var PackedModule; s: PSym) =
+  assert s.kind != skUnknown
   let nameId = getOrIncl(m.strings, s.name.s)
   m.hidden.add((nameId, s.itemId.item))
+  assert s.itemId.module == c.thisModule
 
 proc addExported*(c: var PackedEncoder; m: var PackedModule; s: PSym) =
+  assert s.kind != skUnknown
+  assert s.itemId.module == c.thisModule
   let nameId = getOrIncl(m.strings, s.name.s)
   m.exports.add((nameId, s.itemId.item))
 
@@ -253,6 +261,8 @@ proc addMethod*(c: var PackedEncoder; m: var PackedModule; s: PSym) =
   m.methods.add s.itemId.item
 
 proc addReexport*(c: var PackedEncoder; m: var PackedModule; s: PSym) =
+  assert s.kind != skUnknown
+  if s.kind == skModule: return
   let nameId = getOrIncl(m.strings, s.name.s)
   m.reexports.add((nameId, PackedItemId(module: toLitId(s.itemId.module.FileIndex, c, m),
                                         item: s.itemId.item)))
@@ -284,7 +294,8 @@ proc toLitId(x: BiggestInt; m: var PackedModule): LitId =
   result = getOrIncl(m.numbers, x)
 
 proc toPackedInfo(x: TLineInfo; c: var PackedEncoder; m: var PackedModule): PackedLineInfo =
-  PackedLineInfo(line: x.line, col: x.col, file: toLitId(x.fileIndex, c, m))
+  pack(m.man, toLitId(x.fileIndex, c, m), x.line.int32, x.col.int32)
+  #PackedLineInfo(line: x.line, col: x.col, file: toLitId(x.fileIndex, c, m))
 
 proc safeItemId(s: PSym; c: var PackedEncoder; m: var PackedModule): PackedItemId {.inline.} =
   ## given a symbol, produce an ItemId with the correct properties
@@ -336,7 +347,7 @@ proc storeTypeLater(t: PType; c: var PackedEncoder; m: var PackedModule): Packed
 proc storeSymLater(s: PSym; c: var PackedEncoder; m: var PackedModule): PackedItemId =
   if s.isNil: return nilItemId
   assert s.itemId.module >= 0
-  assert s.itemId.module >= 0
+  assert s.itemId.item >= 0
   result = PackedItemId(module: toLitId(s.itemId.module.FileIndex, c, m), item: s.itemId.item)
   if s.itemId.module == c.thisModule:
     # the sym belongs to this module, so serialize it here, eventually.
@@ -351,15 +362,15 @@ proc storeType(t: PType; c: var PackedEncoder; m: var PackedModule): PackedItemI
   result = PackedItemId(module: toLitId(t.uniqueId.module.FileIndex, c, m), item: t.uniqueId.item)
 
   if t.uniqueId.module == c.thisModule and not c.typeMarker.containsOrIncl(t.uniqueId.item):
-    if t.uniqueId.item >= m.types.len:
-      setLen m.types, t.uniqueId.item+1
+    #if t.uniqueId.item >= m.types.len:
+    #  setLen m.types, t.uniqueId.item+1
 
-    var p = PackedType(kind: t.kind, flags: t.flags, callConv: t.callConv,
+    var p = PackedType(id: t.uniqueId.item, kind: t.kind, flags: t.flags, callConv: t.callConv,
       size: t.size, align: t.align, nonUniqueId: t.itemId.item,
       paddingAtEnd: t.paddingAtEnd)
     storeNode(p, t, n)
     p.typeInst = t.typeInst.storeType(c, m)
-    for kid in items t.sons:
+    for kid in kids t:
       p.types.add kid.storeType(c, m)
     c.addMissing t.sym
     p.sym = t.sym.safeItemId(c, m)
@@ -372,10 +383,9 @@ proc storeType(t: PType; c: var PackedEncoder; m: var PackedModule): PackedItemI
 proc toPackedLib(l: PLib; c: var PackedEncoder; m: var PackedModule): PackedLib =
   ## the plib hangs off the psym via the .annex field
   if l.isNil: return
-  result.kind = l.kind
-  result.generated = l.generated
-  result.isOverridden = l.isOverridden
-  result.name = toLitId($l.name, m)
+  result = PackedLib(kind: l.kind, generated: l.generated,
+    isOverridden: l.isOverridden, name: toLitId($l.name, m)
+  )
   storeNode(result, l, path)
 
 proc storeSym*(s: PSym; c: var PackedEncoder; m: var PackedModule): PackedItemId =
@@ -386,12 +396,12 @@ proc storeSym*(s: PSym; c: var PackedEncoder; m: var PackedModule): PackedItemId
   result = PackedItemId(module: toLitId(s.itemId.module.FileIndex, c, m), item: s.itemId.item)
 
   if s.itemId.module == c.thisModule and not c.symMarker.containsOrIncl(s.itemId.item):
-    if s.itemId.item >= m.syms.len:
-      setLen m.syms, s.itemId.item+1
+    #if s.itemId.item >= m.syms.len:
+    #  setLen m.syms, s.itemId.item+1
 
     assert sfForward notin s.flags
 
-    var p = PackedSym(kind: s.kind, flags: s.flags, info: s.info.toPackedInfo(c, m), magic: s.magic,
+    var p = PackedSym(id: s.itemId.item, kind: s.kind, flags: s.flags, info: s.info.toPackedInfo(c, m), magic: s.magic,
       position: s.position, offset: s.offset, disamb: s.disamb, options: s.options,
       name: s.name.s.toLitId(m))
 
@@ -404,7 +414,7 @@ proc storeSym*(s: PSym; c: var PackedEncoder; m: var PackedModule): PackedItemId
       p.bitsize = s.bitsize
       p.alignment = s.alignment
 
-    p.externalName = toLitId(s.loc.r, m)
+    p.externalName = toLitId(s.loc.snippet, m)
     p.locFlags = s.loc.flags
     c.addMissing s.typ
     p.typ = s.typ.storeType(c, m)
@@ -413,6 +423,7 @@ proc storeSym*(s: PSym; c: var PackedEncoder; m: var PackedModule): PackedItemId
     p.annex = toPackedLib(s.annex, c, m)
     when hasFFI:
       p.cname = toLitId(s.cname, m)
+    p.instantiatedFrom = s.instantiatedFrom.safeItemId(c, m)
 
     # fill the reserved slot, nothing else:
     m.syms[s.itemId.item] = p
@@ -420,53 +431,59 @@ proc storeSym*(s: PSym; c: var PackedEncoder; m: var PackedModule): PackedItemId
 proc addModuleRef(n: PNode; ir: var PackedTree; c: var PackedEncoder; m: var PackedModule) =
   ## add a remote symbol reference to the tree
   let info = n.info.toPackedInfo(c, m)
-  ir.nodes.add PackedNode(kind: nkModuleRef, operand: 3.int32, # spans 3 nodes in total
-                          typeId: storeTypeLater(n.typ, c, m), info: info, flags: n.flags)
-  ir.nodes.add PackedNode(kind: nkInt32Lit, info: info,
-                          operand: toLitId(n.sym.itemId.module.FileIndex, c, m).int32)
-  ir.nodes.add PackedNode(kind: nkInt32Lit, info: info,
-                          operand: n.sym.itemId.item)
+  if n.typ != n.sym.typ:
+    ir.addNode(kind = nkModuleRef, operand = 3.int32, # spans 3 nodes in total
+               info = info, flags = n.flags,
+               typeId = storeTypeLater(n.typ, c, m))
+  else:
+    ir.addNode(kind = nkModuleRef, operand = 3.int32, # spans 3 nodes in total
+              info = info, flags = n.flags)
+  ir.addNode(kind = nkNone, info = info,
+             operand = toLitId(n.sym.itemId.module.FileIndex, c, m).int32)
+  ir.addNode(kind = nkNone, info = info,
+             operand = n.sym.itemId.item)
 
 proc toPackedNode*(n: PNode; ir: var PackedTree; c: var PackedEncoder; m: var PackedModule) =
   ## serialize a node into the tree
   if n == nil:
-    ir.nodes.add PackedNode(kind: nkNilRodNode, flags: {}, operand: 1)
+    ir.addNode(kind = nkNilRodNode, operand = 1, info = NoLineInfo)
     return
   let info = toPackedInfo(n.info, c, m)
   case n.kind
   of nkNone, nkEmpty, nkNilLit, nkType:
-    ir.nodes.add PackedNode(kind: n.kind, flags: n.flags, operand: 0,
-                            typeId: storeTypeLater(n.typ, c, m), info: info)
+    ir.addNode(kind = n.kind, flags = n.flags, operand = 0,
+               typeId = storeTypeLater(n.typ, c, m), info = info)
   of nkIdent:
-    ir.nodes.add PackedNode(kind: n.kind, flags: n.flags,
-                            operand: int32 getOrIncl(m.strings, n.ident.s),
-                            typeId: storeTypeLater(n.typ, c, m), info: info)
+    ir.addNode(kind = n.kind, flags = n.flags,
+                operand = int32 getOrIncl(m.strings, n.ident.s),
+                typeId = storeTypeLater(n.typ, c, m), info = info)
   of nkSym:
     if n.sym.itemId.module == c.thisModule:
       # it is a symbol that belongs to the module we're currently
       # packing:
       let id = n.sym.storeSymLater(c, m).item
-      ir.nodes.add PackedNode(kind: nkSym, flags: n.flags, operand: id,
-                              typeId: storeTypeLater(n.typ, c, m), info: info)
+      if n.typ != n.sym.typ:
+        ir.addNode(kind = nkSym, flags = n.flags, operand = id,
+                   info = info,
+                   typeId = storeTypeLater(n.typ, c, m))
+      else:
+        ir.addNode(kind = nkSym, flags = n.flags, operand = id,
+                   info = info)
     else:
       # store it as an external module reference:
       addModuleRef(n, ir, c, m)
-  of directIntLit:
-    ir.nodes.add PackedNode(kind: n.kind, flags: n.flags,
-                            operand: int32(n.intVal),
-                            typeId: storeTypeLater(n.typ, c, m), info: info)
   of externIntLit:
-    ir.nodes.add PackedNode(kind: n.kind, flags: n.flags,
-                            operand: int32 getOrIncl(m.numbers, n.intVal),
-                            typeId: storeTypeLater(n.typ, c, m), info: info)
+    ir.addNode(kind = n.kind, flags = n.flags,
+               operand = int32 getOrIncl(m.numbers, n.intVal),
+               typeId = storeTypeLater(n.typ, c, m), info = info)
   of nkStrLit..nkTripleStrLit:
-    ir.nodes.add PackedNode(kind: n.kind, flags: n.flags,
-                            operand: int32 getOrIncl(m.strings, n.strVal),
-                            typeId: storeTypeLater(n.typ, c, m), info: info)
+    ir.addNode(kind = n.kind, flags = n.flags,
+               operand = int32 getOrIncl(m.strings, n.strVal),
+               typeId = storeTypeLater(n.typ, c, m), info = info)
   of nkFloatLit..nkFloat128Lit:
-    ir.nodes.add PackedNode(kind: n.kind, flags: n.flags,
-                            operand: int32 getOrIncl(m.numbers, cast[BiggestInt](n.floatVal)),
-                            typeId: storeTypeLater(n.typ, c, m), info: info)
+    ir.addNode(kind = n.kind, flags = n.flags,
+               operand = int32 getOrIncl(m.numbers, cast[BiggestInt](n.floatVal)),
+               typeId = storeTypeLater(n.typ, c, m), info = info)
   else:
     let patchPos = ir.prepare(n.kind, n.flags,
                               storeTypeLater(n.typ, c, m), info)
@@ -491,8 +508,8 @@ proc toPackedProcDef(n: PNode; ir: var PackedTree; c: var PackedEncoder; m: var
       # do not serialize the body of the proc, it's unnecessary since
       # n[0].sym.ast has the sem'checked variant of it which is what
       # everybody should use instead.
-      ir.nodes.add PackedNode(kind: nkEmpty, flags: {}, operand: 0,
-                              typeId: nilItemId, info: info)
+      ir.addNode(kind = nkEmpty, flags = {}, operand = 0,
+                 typeId = nilItemId, info = info)
   ir.patch patchPos
 
 proc toPackedNodeIgnoreProcDefs(n: PNode, encoder: var PackedEncoder; m: var PackedModule) =
@@ -565,6 +582,20 @@ proc toRodFile*(conf: ConfigRef; f: AbsoluteFile; ext = RodExt): AbsoluteFile =
   result = changeFileExt(completeGeneratedFilePath(conf,
     mangleModuleName(conf, f).AbsoluteFile), ext)
 
+const
+  BenchIC* = false
+
+when BenchIC:
+  var gloadBodies: MonoTime
+
+  template bench(x, body) =
+    let start = getMonoTime()
+    body
+    x = x + (getMonoTime() - start)
+
+else:
+  template bench(x, body) = body
+
 proc loadRodFile*(filename: AbsoluteFile; m: var PackedModule; config: ConfigRef;
                   ignoreConfig = false): RodFileError =
   var f = rodfiles.open(filename.string)
@@ -582,6 +613,10 @@ proc loadRodFile*(filename: AbsoluteFile; m: var PackedModule; config: ConfigRef
     f.loadSection section
     f.loadSeq data
 
+  template loadTableSection(section, data) {.dirty.} =
+    f.loadSection section
+    f.loadOrderedTable data
+
   template loadTabSection(section, data) {.dirty.} =
     f.loadSection section
     f.load data
@@ -589,40 +624,48 @@ proc loadRodFile*(filename: AbsoluteFile; m: var PackedModule; config: ConfigRef
   loadTabSection stringsSection, m.strings
 
   loadSeqSection checkSumsSection, m.includes
-  if not includesIdentical(m, config):
+  if config.cmd != cmdM and not includesIdentical(m, config):
     f.err = includeFileChanged
 
   loadSeqSection depsSection, m.imports
 
-  loadTabSection numbersSection, m.numbers
+  bench gloadBodies:
 
-  loadSeqSection exportsSection, m.exports
-  loadSeqSection hiddenSection, m.hidden
-  loadSeqSection reexportsSection, m.reexports
+    loadTabSection numbersSection, m.numbers
 
-  loadSeqSection compilerProcsSection, m.compilerProcs
+    loadSeqSection exportsSection, m.exports
+    loadSeqSection hiddenSection, m.hidden
+    loadSeqSection reexportsSection, m.reexports
 
-  loadSeqSection trmacrosSection, m.trmacros
+    loadSeqSection compilerProcsSection, m.compilerProcs
 
-  loadSeqSection convertersSection, m.converters
-  loadSeqSection methodsSection, m.methods
-  loadSeqSection pureEnumsSection, m.pureEnums
+    loadSeqSection trmacrosSection, m.trmacros
 
-  loadSeqSection toReplaySection, m.toReplay.nodes
-  loadSeqSection topLevelSection, m.topLevel.nodes
-  loadSeqSection bodiesSection, m.bodies.nodes
-  loadSeqSection symsSection, m.syms
-  loadSeqSection typesSection, m.types
+    loadSeqSection convertersSection, m.converters
+    loadSeqSection methodsSection, m.methods
+    loadSeqSection pureEnumsSection, m.pureEnums
 
-  loadSeqSection typeInstCacheSection, m.typeInstCache
-  loadSeqSection procInstCacheSection, m.procInstCache
-  loadSeqSection attachedOpsSection, m.attachedOps
-  loadSeqSection methodsPerTypeSection, m.methodsPerType
-  loadSeqSection enumToStringProcsSection, m.enumToStringProcs
-  loadSeqSection typeInfoSection, m.emittedTypeInfo
+    loadTabSection toReplaySection, m.toReplay
+    loadTabSection topLevelSection, m.topLevel
 
-  f.loadSection backendFlagsSection
-  f.loadPrim m.backendFlags
+    loadTabSection bodiesSection, m.bodies
+    loadTableSection symsSection, m.syms
+    loadTableSection typesSection, m.types
+
+    loadSeqSection typeInstCacheSection, m.typeInstCache
+    loadSeqSection procInstCacheSection, m.procInstCache
+    loadSeqSection attachedOpsSection, m.attachedOps
+    loadSeqSection methodsPerGenericTypeSection, m.methodsPerGenericType
+    loadSeqSection enumToStringProcsSection, m.enumToStringProcs
+    loadSeqSection methodsPerTypeSection, m.methodsPerType
+    loadSeqSection dispatchersSection, m.dispatchers
+    loadSeqSection typeInfoSection, m.emittedTypeInfo
+
+    f.loadSection backendFlagsSection
+    f.loadPrim m.backendFlags
+
+    f.loadSection sideChannelSection
+  f.load m.man
 
   close(f)
   result = f.err
@@ -652,6 +695,10 @@ proc saveRodFile*(filename: AbsoluteFile; encoder: var PackedEncoder; m: var Pac
     f.storeSection section
     f.store data
 
+  template storeTableSection(section, data) {.dirty.} =
+    f.storeSection section
+    f.storeOrderedTable data
+
   storeTabSection stringsSection, m.strings
 
   storeSeqSection checkSumsSection, m.includes
@@ -671,24 +718,29 @@ proc saveRodFile*(filename: AbsoluteFile; encoder: var PackedEncoder; m: var Pac
   storeSeqSection methodsSection, m.methods
   storeSeqSection pureEnumsSection, m.pureEnums
 
-  storeSeqSection toReplaySection, m.toReplay.nodes
-  storeSeqSection topLevelSection, m.topLevel.nodes
+  storeTabSection toReplaySection, m.toReplay
+  storeTabSection topLevelSection, m.topLevel
 
-  storeSeqSection bodiesSection, m.bodies.nodes
-  storeSeqSection symsSection, m.syms
+  storeTabSection bodiesSection, m.bodies
+  storeTableSection symsSection, m.syms
 
-  storeSeqSection typesSection, m.types
+  storeTableSection typesSection, m.types
 
   storeSeqSection typeInstCacheSection, m.typeInstCache
   storeSeqSection procInstCacheSection, m.procInstCache
   storeSeqSection attachedOpsSection, m.attachedOps
-  storeSeqSection methodsPerTypeSection, m.methodsPerType
+  storeSeqSection methodsPerGenericTypeSection, m.methodsPerGenericType
   storeSeqSection enumToStringProcsSection, m.enumToStringProcs
+  storeSeqSection methodsPerTypeSection, m.methodsPerType
+  storeSeqSection dispatchersSection, m.dispatchers
   storeSeqSection typeInfoSection, m.emittedTypeInfo
 
   f.storeSection backendFlagsSection
   f.storePrim m.backendFlags
 
+  f.storeSection sideChannelSection
+  f.store m.man
+
   close(f)
   encoder.disable()
   if f.err != ok:
@@ -723,20 +775,36 @@ type
     status*: ModuleStatus
     symsInit, typesInit, loadedButAliveSetChanged*: bool
     fromDisk*: PackedModule
-    syms: seq[PSym] # indexed by itemId
-    types: seq[PType]
+    syms: OrderedTable[int32, PSym] # indexed by itemId
+    types: OrderedTable[int32, PType]
     module*: PSym # the one true module symbol.
     iface, ifaceHidden: Table[PIdent, seq[PackedItemId]]
       # PackedItemId so that it works with reexported symbols too
       # ifaceHidden includes private symbols
 
-  PackedModuleGraph* = seq[LoadedModule] # indexed by FileIndex
+type
+  PackedModuleGraph* = object
+    pm*: seq[LoadedModule] # indexed by FileIndex
+    when BenchIC:
+      depAnalysis: MonoTime
+      loadBody: MonoTime
+      loadSym, loadType, loadBodies: MonoTime
+
+when BenchIC:
+  proc echoTimes*(m: PackedModuleGraph) =
+    echo "analysis: ", m.depAnalysis, " loadBody: ", m.loadBody, " loadSym: ",
+      m.loadSym, " loadType: ", m.loadType, " all bodies: ", gloadBodies
+
+template `[]`*(m: PackedModuleGraph; i: int): LoadedModule = m.pm[i]
+template len*(m: PackedModuleGraph): int = m.pm.len
 
 proc loadType(c: var PackedDecoder; g: var PackedModuleGraph; thisModule: int; t: PackedItemId): PType
 proc loadSym(c: var PackedDecoder; g: var PackedModuleGraph; thisModule: int; s: PackedItemId): PSym
 
 proc toFileIndexCached*(c: var PackedDecoder; g: PackedModuleGraph; thisModule: int; f: LitId): FileIndex =
-  if c.lastLit == f and c.lastModule == thisModule:
+  if f == LitId(0):
+    result = InvalidFileIdx
+  elif c.lastLit == f and c.lastModule == thisModule:
     result = c.lastFile
   else:
     result = toFileIndex(f, g[thisModule].fromDisk, c.config)
@@ -747,8 +815,9 @@ proc toFileIndexCached*(c: var PackedDecoder; g: PackedModuleGraph; thisModule:
 proc translateLineInfo(c: var PackedDecoder; g: var PackedModuleGraph; thisModule: int;
                        x: PackedLineInfo): TLineInfo =
   assert g[thisModule].status in {loaded, storing, stored}
-  result = TLineInfo(line: x.line, col: x.col,
-            fileIndex: toFileIndexCached(c, g, thisModule, x.file))
+  let (fileId, line, col) = unpack(g[thisModule].fromDisk.man, x)
+  result = TLineInfo(line: line.uint16, col: col.int16,
+            fileIndex: toFileIndexCached(c, g, thisModule, fileId))
 
 proc loadNodes*(c: var PackedDecoder; g: var PackedModuleGraph; thisModule: int;
                 tree: PackedTree; n: NodePos): PNode =
@@ -762,14 +831,14 @@ proc loadNodes*(c: var PackedDecoder; g: var PackedModuleGraph; thisModule: int;
   result.flags = n.flags
 
   case k
-  of nkEmpty, nkNilLit, nkType:
+  of nkNone, nkEmpty, nkNilLit, nkType:
     discard
   of nkIdent:
     result.ident = getIdent(c.cache, g[thisModule].fromDisk.strings[n.litId])
   of nkSym:
-    result.sym = loadSym(c, g, thisModule, PackedItemId(module: LitId(0), item: tree.nodes[n.int].operand))
-  of directIntLit:
-    result.intVal = tree.nodes[n.int].operand
+    result.sym = loadSym(c, g, thisModule, PackedItemId(module: LitId(0), item: tree[n].soperand))
+    if result.typ == nil:
+      result.typ() = result.sym.typ
   of externIntLit:
     result.intVal = g[thisModule].fromDisk.numbers[n.litId]
   of nkStrLit..nkTripleStrLit:
@@ -778,10 +847,12 @@ proc loadNodes*(c: var PackedDecoder; g: var PackedModuleGraph; thisModule: int;
     result.floatVal = cast[BiggestFloat](g[thisModule].fromDisk.numbers[n.litId])
   of nkModuleRef:
     let (n1, n2) = sons2(tree, n)
-    assert n1.kind == nkInt32Lit
-    assert n2.kind == nkInt32Lit
+    assert n1.kind == nkNone
+    assert n2.kind == nkNone
     transitionNoneToSym(result)
-    result.sym = loadSym(c, g, thisModule, PackedItemId(module: n1.litId, item: tree.nodes[n2.int].operand))
+    result.sym = loadSym(c, g, thisModule, PackedItemId(module: n1.litId, item: tree[n2].soperand))
+    if result.typ == nil:
+      result.typ() = result.sym.typ
   else:
     for n0 in sonsReadonly(tree, n):
       result.addAllowNil loadNodes(c, g, thisModule, tree, n0)
@@ -813,6 +884,7 @@ proc loadProcHeader(c: var PackedDecoder; g: var PackedModuleGraph; thisModule:
 
 proc loadProcBody(c: var PackedDecoder; g: var PackedModuleGraph; thisModule: int;
                   tree: PackedTree; n: NodePos): PNode =
+  result = nil
   var i = 0
   for n0 in sonsReadonly(tree, n):
     if i == bodyPos:
@@ -870,23 +942,38 @@ proc symBodyFromPacked(c: var PackedDecoder; g: var PackedModuleGraph;
     result.guard = loadSym(c, g, si, s.guard)
     result.bitsize = s.bitsize
     result.alignment = s.alignment
-  result.owner = loadSym(c, g, si, s.owner)
+  setOwner(result, loadSym(c, g, si, s.owner))
   let externalName = g[si].fromDisk.strings[s.externalName]
   if externalName != "":
-    result.loc.r = rope externalName
+    result.loc.snippet = externalName
   result.loc.flags = s.locFlags
+  result.instantiatedFrom = loadSym(c, g, si, s.instantiatedFrom)
+
+proc needsRecompile(g: var PackedModuleGraph; conf: ConfigRef; cache: IdentCache;
+                    fileIdx: FileIndex; cachedModules: var seq[FileIndex]): bool
+proc loadToReplayNodes(g: var PackedModuleGraph; conf: ConfigRef; cache: IdentCache;
+                       fileIdx: FileIndex; m: var LoadedModule)
 
 proc loadSym(c: var PackedDecoder; g: var PackedModuleGraph; thisModule: int; s: PackedItemId): PSym =
   if s == nilItemId:
     result = nil
   else:
     let si = moduleIndex(c, g, thisModule, s)
-    assert g[si].status in {loaded, storing, stored}
-    if not g[si].symsInit:
-      g[si].symsInit = true
-      setLen g[si].syms, g[si].fromDisk.syms.len
+    if si >= g.len:
+      g.pm.setLen(si+1)
 
-    if g[si].syms[s.item] == nil:
+    if g[si].status == undefined and c.config.cmd == cmdM:
+      var cachedModules: seq[FileIndex] = @[]
+      discard needsRecompile(g, c.config, c.cache, FileIndex(si), cachedModules)
+      for m in cachedModules:
+        loadToReplayNodes(g, c.config, c.cache, m, g[int m])
+
+    assert g[si].status in {loaded, storing, stored}
+    #if not g[si].symsInit:
+    #  g[si].symsInit = true
+    #  setLen g[si].syms, g[si].fromDisk.syms.len
+
+    if g[si].syms.getOrDefault(s.item) == nil:
       if g[si].fromDisk.syms[s.item].kind != skModule:
         result = symHeaderFromPacked(c, g, g[si].fromDisk.syms[s.item], si, s.item)
         # store it here early on, so that recursions work properly:
@@ -895,6 +982,7 @@ proc loadSym(c: var PackedDecoder; g: var PackedModuleGraph; thisModule: int; s:
       else:
         result = g[si].module
         assert result != nil
+        g[si].syms[s.item] = result
 
     else:
       result = g[si].syms[s.item]
@@ -910,13 +998,15 @@ proc typeHeaderFromPacked(c: var PackedDecoder; g: var PackedModuleGraph;
 proc typeBodyFromPacked(c: var PackedDecoder; g: var PackedModuleGraph;
                         t: PackedType; si, item: int32; result: PType) =
   result.sym = loadSym(c, g, si, t.sym)
-  result.owner = loadSym(c, g, si, t.owner)
+  setOwner(result, loadSym(c, g, si, t.owner))
   when false:
     for op, item in pairs t.attachedOps:
       result.attachedOps[op] = loadSym(c, g, si, item)
   result.typeInst = loadType(c, g, si, t.typeInst)
+  var sons = newSeq[PType]()
   for son in items t.types:
-    result.sons.add loadType(c, g, si, son)
+    sons.add loadType(c, g, si, son)
+  result.setSons(sons)
   loadAstBody(t, n)
   when false:
     for gen, id in items t.methods:
@@ -930,18 +1020,20 @@ proc loadType(c: var PackedDecoder; g: var PackedModuleGraph; thisModule: int; t
     assert g[si].status in {loaded, storing, stored}
     assert t.item > 0
 
-    if not g[si].typesInit:
-      g[si].typesInit = true
-      setLen g[si].types, g[si].fromDisk.types.len
+    #if not g[si].typesInit:
+    #  g[si].typesInit = true
+    #  setLen g[si].types, g[si].fromDisk.types.len
 
-    if g[si].types[t.item] == nil:
+    if g[si].types.getOrDefault(t.item) == nil:
       result = typeHeaderFromPacked(c, g, g[si].fromDisk.types[t.item], si, t.item)
       # store it here early on, so that recursions work properly:
       g[si].types[t.item] = result
       typeBodyFromPacked(c, g, g[si].fromDisk.types[t.item], si, t.item, result)
+      #assert result.itemId.item == t.item, $(result.itemId.item, t.item)
+      assert result.itemId.item > 0, $(result.itemId.item, t.item)
     else:
       result = g[si].types[t.item]
-    assert result.itemId.item > 0
+      assert result.itemId.item > 0, "2"
 
 proc setupLookupTables(g: var PackedModuleGraph; conf: ConfigRef; cache: IdentCache;
                        fileIdx: FileIndex; m: var LoadedModule) =
@@ -970,7 +1062,7 @@ proc setupLookupTables(g: var PackedModuleGraph; conf: ConfigRef; cache: IdentCa
                   name: getIdent(cache, splitFile(filename).name),
                   info: newLineInfo(fileIdx, 1, 1),
                   position: int(fileIdx))
-  m.module.owner = getPackage(conf, cache, fileIdx)
+  setOwner(m.module, getPackage(conf, cache, fileIdx))
   m.module.flags = m.fromDisk.moduleFlags
 
 proc loadToReplayNodes(g: var PackedModuleGraph; conf: ConfigRef; cache: IdentCache;
@@ -991,30 +1083,37 @@ proc needsRecompile(g: var PackedModuleGraph; conf: ConfigRef; cache: IdentCache
   # Does the file belong to the fileIdx need to be recompiled?
   let m = int(fileIdx)
   if m >= g.len:
-    g.setLen(m+1)
+    g.pm.setLen(m+1)
 
   case g[m].status
   of undefined:
     g[m].status = loading
     let fullpath = msgs.toFullPath(conf, fileIdx)
     let rod = toRodFile(conf, AbsoluteFile fullpath)
-    let err = loadRodFile(rod, g[m].fromDisk, conf)
+    let err = loadRodFile(rod, g[m].fromDisk, conf, ignoreConfig = conf.cmd == cmdM)
     if err == ok:
-      result = optForceFullMake in conf.globalOptions
-      # check its dependencies:
-      for dep in g[m].fromDisk.imports:
-        let fid = toFileIndex(dep, g[m].fromDisk, conf)
-        # Warning: we need to traverse the full graph, so
-        # do **not use break here**!
-        if needsRecompile(g, conf, cache, fid, cachedModules):
-          result = true
-
-      if not result:
+      if conf.cmd == cmdM:
         setupLookupTables(g, conf, cache, fileIdx, g[m])
         cachedModules.add fileIdx
         g[m].status = loaded
+        result = false
       else:
-        g[m] = LoadedModule(status: outdated, module: g[m].module)
+        result = optForceFullMake in conf.globalOptions
+        # check its dependencies:
+        let imp = g[m].fromDisk.imports
+        for dep in imp:
+          let fid = toFileIndex(dep, g[m].fromDisk, conf)
+          # Warning: we need to traverse the full graph, so
+          # do **not use break here**!
+          if needsRecompile(g, conf, cache, fid, cachedModules):
+            result = true
+
+        if not result:
+          setupLookupTables(g, conf, cache, fileIdx, g[m])
+          cachedModules.add fileIdx
+          g[m].status = loaded
+        else:
+          g.pm[m] = LoadedModule(status: outdated, module: g[m].module)
     else:
       loadError(err, rod, conf)
       g[m].status = outdated
@@ -1029,12 +1128,13 @@ proc needsRecompile(g: var PackedModuleGraph; conf: ConfigRef; cache: IdentCache
 proc moduleFromRodFile*(g: var PackedModuleGraph; conf: ConfigRef; cache: IdentCache;
                         fileIdx: FileIndex; cachedModules: var seq[FileIndex]): PSym =
   ## Returns 'nil' if the module needs to be recompiled.
-  if needsRecompile(g, conf, cache, fileIdx, cachedModules):
-    result = nil
-  else:
-    result = g[int fileIdx].module
-    assert result != nil
-    assert result.position == int(fileIdx)
+  bench g.depAnalysis:
+    if needsRecompile(g, conf, cache, fileIdx, cachedModules):
+      result = nil
+    else:
+      result = g[int fileIdx].module
+      assert result != nil
+      assert result.position == int(fileIdx)
   for m in cachedModules:
     loadToReplayNodes(g, conf, cache, m, g[int m])
 
@@ -1048,46 +1148,43 @@ template setupDecoder() {.dirty.} =
 
 proc loadProcBody*(config: ConfigRef, cache: IdentCache;
                    g: var PackedModuleGraph; s: PSym): PNode =
-  let mId = s.itemId.module
-  var decoder = PackedDecoder(
-    lastModule: int32(-1),
-    lastLit: LitId(0),
-    lastFile: FileIndex(-1),
-    config: config,
-    cache: cache)
-  let pos = g[mId].fromDisk.syms[s.itemId.item].ast
-  assert pos != emptyNodeId
-  result = loadProcBody(decoder, g, mId, g[mId].fromDisk.bodies, NodePos pos)
+  bench g.loadBody:
+    let mId = s.itemId.module
+    var decoder = PackedDecoder(
+      lastModule: int32(-1),
+      lastLit: LitId(0),
+      lastFile: FileIndex(-1),
+      config: config,
+      cache: cache)
+    let pos = g[mId].fromDisk.syms[s.itemId.item].ast
+    assert pos != emptyNodeId
+    result = loadProcBody(decoder, g, mId, g[mId].fromDisk.bodies, NodePos pos)
 
 proc loadTypeFromId*(config: ConfigRef, cache: IdentCache;
                      g: var PackedModuleGraph; module: int; id: PackedItemId): PType =
-  if id.item < g[module].types.len:
-    result = g[module].types[id.item]
-  else:
-    result = nil
-  if result == nil:
-    var decoder = PackedDecoder(
-      lastModule: int32(-1),
-      lastLit: LitId(0),
-      lastFile: FileIndex(-1),
-      config: config,
-      cache: cache)
-    result = loadType(decoder, g, module, id)
+  bench g.loadType:
+    result = g[module].types.getOrDefault(id.item)
+    if result == nil:
+      var decoder = PackedDecoder(
+        lastModule: int32(-1),
+        lastLit: LitId(0),
+        lastFile: FileIndex(-1),
+        config: config,
+        cache: cache)
+      result = loadType(decoder, g, module, id)
 
 proc loadSymFromId*(config: ConfigRef, cache: IdentCache;
                     g: var PackedModuleGraph; module: int; id: PackedItemId): PSym =
-  if id.item < g[module].syms.len:
-    result = g[module].syms[id.item]
-  else:
-    result = nil
-  if result == nil:
-    var decoder = PackedDecoder(
-      lastModule: int32(-1),
-      lastLit: LitId(0),
-      lastFile: FileIndex(-1),
-      config: config,
-      cache: cache)
-    result = loadSym(decoder, g, module, id)
+  bench g.loadSym:
+    result = g[module].syms.getOrDefault(id.item)
+    if result == nil:
+      var decoder = PackedDecoder(
+        lastModule: int32(-1),
+        lastLit: LitId(0),
+        lastFile: FileIndex(-1),
+        config: config,
+        cache: cache)
+      result = loadSym(decoder, g, module, id)
 
 proc translateId*(id: PackedItemId; g: PackedModuleGraph; thisModule: int; config: ConfigRef): ItemId =
   if id.module == LitId(0):
@@ -1095,19 +1192,6 @@ proc translateId*(id: PackedItemId; g: PackedModuleGraph; thisModule: int; confi
   else:
     ItemId(module: toFileIndex(id.module, g[thisModule].fromDisk, config).int32, item: id.item)
 
-proc checkForHoles(m: PackedModule; config: ConfigRef; moduleId: int) =
-  var bugs = 0
-  for i in 1 .. high(m.syms):
-    if m.syms[i].kind == skUnknown:
-      echo "EMPTY ID ", i, " module ", moduleId, " ", toFullPath(config, FileIndex(moduleId))
-      inc bugs
-  assert bugs == 0
-  when false:
-    var nones = 0
-    for i in 1 .. high(m.types):
-      inc nones, m.types[i].kind == tyNone
-    assert nones < 1
-
 proc simulateLoadedModule*(g: var PackedModuleGraph; conf: ConfigRef; cache: IdentCache;
                            moduleSym: PSym; m: PackedModule) =
   # For now only used for heavy debugging. In the future we could use this to reduce the
@@ -1147,9 +1231,11 @@ proc initRodIter*(it: var RodIter; config: ConfigRef, cache: IdentCache;
   if it.i < it.values.len:
     result = loadSym(it.decoder, g, int(module), it.values[it.i])
     inc it.i
+  else:
+    result = nil
 
 proc initRodIterAllSyms*(it: var RodIter; config: ConfigRef, cache: IdentCache;
-                         g: var PackedModuleGraph; module: FileIndex, importHidden: bool): PSym =
+                         g: var PackedModuleGraph; module: FileIndex; importHidden: bool): PSym =
   it.decoder = PackedDecoder(
     lastModule: int32(-1),
     lastLit: LitId(0),
@@ -1164,11 +1250,15 @@ proc initRodIterAllSyms*(it: var RodIter; config: ConfigRef, cache: IdentCache;
   if it.i < it.values.len:
     result = loadSym(it.decoder, g, int(module), it.values[it.i])
     inc it.i
+  else:
+    result = nil
 
 proc nextRodIter*(it: var RodIter; g: var PackedModuleGraph): PSym =
   if it.i < it.values.len:
     result = loadSym(it.decoder, g, it.module, it.values[it.i])
     inc it.i
+  else:
+    result = nil
 
 iterator interfaceSymbols*(config: ConfigRef, cache: IdentCache;
                            g: var PackedModuleGraph; module: FileIndex;
@@ -1201,12 +1291,12 @@ proc searchForCompilerproc*(m: LoadedModule; name: string): int32 =
 # ------------------------- .rod file viewer ---------------------------------
 
 proc rodViewer*(rodfile: AbsoluteFile; config: ConfigRef, cache: IdentCache) =
-  var m: PackedModule
+  var m: PackedModule = PackedModule()
   let err = loadRodFile(rodfile, m, config, ignoreConfig=true)
   if err != ok:
     config.quitOrRaise "Error: could not load: " & $rodfile.string & " reason: " & $err
 
-  when true:
+  when false:
     echo "exports:"
     for ex in m.exports:
       echo "  ", m.strings[ex[0]], " local ID: ", ex[1]
@@ -1222,13 +1312,32 @@ proc rodViewer*(rodfile: AbsoluteFile; config: ConfigRef, cache: IdentCache) =
     for ex in m.hidden:
       echo "  ", m.strings[ex[0]], " local ID: ", ex[1]
 
-  echo "all symbols"
-  for i in 0..high(m.syms):
-    if m.syms[i].name != LitId(0):
-      echo "  ", m.strings[m.syms[i].name], " local ID: ", i, " kind ", m.syms[i].kind
-    else:
-      echo "  <anon symbol?> local ID: ", i, " kind ", m.syms[i].kind
+  when false:
+    echo "all symbols"
+    for i in 0..high(m.syms):
+      if m.syms[i].name != LitId(0):
+        echo "  ", m.strings[m.syms[i].name], " local ID: ", i, " kind ", m.syms[i].kind
+      else:
+        echo "  <anon symbol?> local ID: ", i, " kind ", m.syms[i].kind
 
   echo "symbols: ", m.syms.len, " types: ", m.types.len,
-    " top level nodes: ", m.topLevel.nodes.len, " other nodes: ", m.bodies.nodes.len,
+    " top level nodes: ", m.topLevel.len, " other nodes: ", m.bodies.len,
     " strings: ", m.strings.len, " numbers: ", m.numbers.len
+
+  echo "SIZES:"
+  echo "symbols: ", m.syms.len * sizeof(PackedSym), " types: ", m.types.len * sizeof(PackedType),
+    " top level nodes: ", m.topLevel.len * sizeof(PackedNode),
+    " other nodes: ", m.bodies.len * sizeof(PackedNode),
+    " strings: ", sizeOnDisc(m.strings)
+  when false:
+    var tt = 0
+    var fc = 0
+    for x in m.topLevel:
+      if x.kind == nkSym or x.typeId == nilItemId: inc tt
+      if x.flags == {}: inc fc
+    for x in m.bodies:
+      if x.kind == nkSym or x.typeId == nilItemId: inc tt
+      if x.flags == {}: inc fc
+    let total = float(m.topLevel.len + m.bodies.len)
+    echo "nodes with nil type: ", tt, " in % ", tt.float / total
+    echo "nodes with empty flags: ", fc.float / total

compiler/ic/iclineinfos.nim

@@ -0,0 +1,84 @@
+#
+#
+#           The Nim Compiler
+#        (c) Copyright 2024 Andreas Rumpf
+#
+#    See the file "copying.txt", included in this
+#    distribution, for details about the copyright.
+#
+
+# For the line information we use 32 bits. They are used as follows:
+# Bit 0 (AsideBit): If we have inline line information or not. If not, the
+# remaining 31 bits are used as an index into a seq[(LitId, int, int)].
+#
+# We use 10 bits for the "file ID", this means a program can consist of as much
+# as 1024 different files. (If it uses more files than that, the overflow bit
+# would be set.)
+# This means we have 21 bits left to encode the (line, col) pair. We use 7 bits for the column
+# so 128 is the limit and 14 bits for the line number.
+# The packed representation supports files with up to 16384 lines.
+# Keep in mind that whenever any limit is reached the AsideBit is set and the real line
+# information is kept in a side channel.
+
+import std / assertions
+
+const
+  AsideBit = 1
+  FileBits = 10
+  LineBits = 14
+  ColBits = 7
+  FileMax = (1 shl FileBits) - 1
+  LineMax = (1 shl LineBits) - 1
+  ColMax = (1 shl ColBits) - 1
+
+static:
+  assert AsideBit + FileBits + LineBits + ColBits == 32
+
+import .. / ic / [bitabs, rodfiles] # for LitId
+
+type
+  PackedLineInfo* = distinct uint32
+
+  LineInfoManager* = object
+    aside: seq[(LitId, int32, int32)]
+
+const
+  NoLineInfo* = PackedLineInfo(0'u32)
+
+proc pack*(m: var LineInfoManager; file: LitId; line, col: int32): PackedLineInfo =
+  if file.uint32 <= FileMax.uint32 and line <= LineMax and col <= ColMax:
+    let col = if col < 0'i32: 0'u32 else: col.uint32
+    let line = if line < 0'i32: 0'u32 else: line.uint32
+    # use inline representation:
+    result = PackedLineInfo((file.uint32 shl 1'u32) or (line shl uint32(AsideBit + FileBits)) or
+      (col shl uint32(AsideBit + FileBits + LineBits)))
+  else:
+    result = PackedLineInfo((m.aside.len shl 1) or AsideBit)
+    m.aside.add (file, line, col)
+
+proc unpack*(m: LineInfoManager; i: PackedLineInfo): (LitId, int32, int32) =
+  let i = i.uint32
+  if (i and 1'u32) == 0'u32:
+    # inline representation:
+    result = (LitId((i shr 1'u32) and FileMax.uint32),
+      int32((i shr uint32(AsideBit + FileBits)) and LineMax.uint32),
+      int32((i shr uint32(AsideBit + FileBits + LineBits)) and ColMax.uint32))
+  else:
+    result = m.aside[int(i shr 1'u32)]
+
+proc getFileId*(m: LineInfoManager; i: PackedLineInfo): LitId =
+  result = unpack(m, i)[0]
+
+proc store*(r: var RodFile; m: LineInfoManager) = storeSeq(r, m.aside)
+proc load*(r: var RodFile; m: var LineInfoManager) = loadSeq(r, m.aside)
+
+when isMainModule:
+  var m = LineInfoManager(aside: @[])
+  for i in 0'i32..<16388'i32:
+    for col in 0'i32..<100'i32:
+      let packed = pack(m, LitId(1023), i, col)
+      let u = unpack(m, packed)
+      assert u[0] == LitId(1023)
+      assert u[1] == i
+      assert u[2] == col
+  echo m.aside.len

compiler/ic/integrity.nim

@@ -10,7 +10,7 @@
 ## Integrity checking for a set of .rod files.
 ## The set must cover a complete Nim project.
 
-import sets
+import std/[sets, tables]
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
@@ -72,15 +72,16 @@ proc checkForeignSym(c: var CheckedContext; symId: PackedItemId) =
     c.thisModule = oldThisModule
 
 proc checkNode(c: var CheckedContext; tree: PackedTree; n: NodePos) =
-  if tree[n.int].typeId != nilItemId:
-    checkType(c, tree[n.int].typeId)
+  let t = findType(tree, n)
+  if t != nilItemId:
+    checkType(c, t)
   case n.kind
   of nkEmpty, nkNilLit, nkType, nkNilRodNode:
     discard
   of nkIdent:
     assert c.g.packed[c.thisModule].fromDisk.strings.hasLitId n.litId
   of nkSym:
-    checkLocalSym(c, tree.nodes[n.int].operand)
+    checkLocalSym(c, tree[n].soperand)
   of directIntLit:
     discard
   of externIntLit, nkFloatLit..nkFloat128Lit:
@@ -89,9 +90,9 @@ proc checkNode(c: var CheckedContext; tree: PackedTree; n: NodePos) =
     assert c.g.packed[c.thisModule].fromDisk.strings.hasLitId n.litId
   of nkModuleRef:
     let (n1, n2) = sons2(tree, n)
-    assert n1.kind == nkInt32Lit
-    assert n2.kind == nkInt32Lit
-    checkForeignSym(c, PackedItemId(module: n1.litId, item: tree.nodes[n2.int].operand))
+    assert n1.kind == nkNone
+    assert n2.kind == nkNone
+    checkForeignSym(c, PackedItemId(module: n1.litId, item: tree[n2].soperand))
   else:
     for n0 in sonsReadonly(tree, n):
       checkNode(c, tree, n0)
@@ -107,18 +108,18 @@ proc checkModule(c: var CheckedContext; m: PackedModule) =
   # We check that:
   # - Every symbol references existing types and symbols.
   # - Every tree node references existing types and symbols.
-  for i in 0..high(m.syms):
-    checkLocalSym c, int32(i)
+  for _, v in pairs(m.syms):
+    checkLocalSym c, v.id
 
   checkTree c, m.toReplay
   checkTree c, m.topLevel
 
   for e in m.exports:
-    assert e[1] >= 0 and e[1] < m.syms.len
+    #assert e[1] >= 0 and e[1] < m.syms.len
     assert e[0] == m.syms[e[1]].name
 
   for e in m.compilerProcs:
-    assert e[1] >= 0 and e[1] < m.syms.len
+    #assert e[1] >= 0 and e[1] < m.syms.len
     assert e[0] == m.syms[e[1]].name
 
   checkLocalSymIds c, m, m.converters
@@ -134,13 +135,15 @@ proc checkModule(c: var CheckedContext; m: PackedModule) =
     typeInstCache*: seq[(PackedItemId, PackedItemId)]
     procInstCache*: seq[PackedInstantiation]
     attachedOps*: seq[(TTypeAttachedOp, PackedItemId, PackedItemId)]
-    methodsPerType*: seq[(PackedItemId, int, PackedItemId)]
+    methodsPerGenericType*: seq[(PackedItemId, int, PackedItemId)]
     enumToStringProcs*: seq[(PackedItemId, PackedItemId)]
+    methodsPerType*: seq[(PackedItemId, PackedItemId)]
+    dispatchers*: seq[PackedItemId]
   ]#
 
 proc checkIntegrity*(g: ModuleGraph) =
   var c = CheckedContext(g: g)
-  for i in 0..high(g.packed):
+  for i in 0..<len(g.packed):
     # case statement here to enforce exhaustive checks.
     case g.packed[i].status
     of undefined:
@@ -150,4 +153,3 @@ proc checkIntegrity*(g: ModuleGraph) =
     of stored, storing, outdated, loaded:
       c.thisModule = int32 i
       checkModule(c, g.packed[i].fromDisk)
-

compiler/ic/navigator.nim

@@ -11,59 +11,70 @@
 ## IDE-like features. It uses the set of .rod files to accomplish
 ## its task. The set must cover a complete Nim project.
 
-import sets
+import std/[sets, tables]
 
-from os import nil
+from std/os import nil
 from std/private/miscdollars import toLocation
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
 
 import ".." / [ast, modulegraphs, msgs, options]
+import iclineinfos
 import packed_ast, bitabs, ic
 
 type
+  UnpackedLineInfo = object
+    file: LitId
+    line, col: int
   NavContext = object
     g: ModuleGraph
     thisModule: int32
-    trackPos: PackedLineInfo
+    trackPos: UnpackedLineInfo
     alreadyEmitted: HashSet[string]
     outputSep: char # for easier testing, use short filenames and spaces instead of tabs.
 
-proc isTracked(current, trackPos: PackedLineInfo, tokenLen: int): bool =
-  if current.file == trackPos.file and current.line == trackPos.line:
+proc isTracked(man: LineInfoManager; current: PackedLineInfo, trackPos: UnpackedLineInfo, tokenLen: int): bool =
+  let (currentFile, currentLine, currentCol) = man.unpack(current)
+  if currentFile == trackPos.file and currentLine == trackPos.line:
     let col = trackPos.col
-    if col >= current.col and col < current.col+tokenLen:
-      return true
+    if col >= currentCol and col < currentCol+tokenLen:
+      result = true
+    else:
+      result = false
+  else:
+    result = false
 
 proc searchLocalSym(c: var NavContext; s: PackedSym; info: PackedLineInfo): bool =
   result = s.name != LitId(0) and
-    isTracked(info, c.trackPos, c.g.packed[c.thisModule].fromDisk.strings[s.name].len)
+    isTracked(c.g.packed[c.thisModule].fromDisk.man, info, c.trackPos, c.g.packed[c.thisModule].fromDisk.strings[s.name].len)
 
 proc searchForeignSym(c: var NavContext; s: ItemId; info: PackedLineInfo): bool =
   let name = c.g.packed[s.module].fromDisk.syms[s.item].name
   result = name != LitId(0) and
-    isTracked(info, c.trackPos, c.g.packed[s.module].fromDisk.strings[name].len)
+    isTracked(c.g.packed[c.thisModule].fromDisk.man, info, c.trackPos, c.g.packed[s.module].fromDisk.strings[name].len)
 
 const
   EmptyItemId = ItemId(module: -1'i32, item: -1'i32)
 
 proc search(c: var NavContext; tree: PackedTree): ItemId =
   # We use the linear representation here directly:
-  for i in 0..high(tree.nodes):
-    case tree.nodes[i].kind
+  for i in 0..<len(tree):
+    let i = NodePos(i)
+    case tree[i].kind
     of nkSym:
-      let item = tree.nodes[i].operand
-      if searchLocalSym(c, c.g.packed[c.thisModule].fromDisk.syms[item], tree.nodes[i].info):
+      let item = tree[i].soperand
+      if searchLocalSym(c, c.g.packed[c.thisModule].fromDisk.syms[item], tree[i].info):
         return ItemId(module: c.thisModule, item: item)
     of nkModuleRef:
-      if tree.nodes[i].info.line == c.trackPos.line and tree.nodes[i].info.file == c.trackPos.file:
-        let (n1, n2) = sons2(tree, NodePos i)
+      let (currentFile, currentLine, currentCol) = c.g.packed[c.thisModule].fromDisk.man.unpack(tree[i].info)
+      if currentLine == c.trackPos.line and currentFile == c.trackPos.file:
+        let (n1, n2) = sons2(tree, i)
         assert n1.kind == nkInt32Lit
         assert n2.kind == nkInt32Lit
-        let pId = PackedItemId(module: n1.litId, item: tree.nodes[n2.int].operand)
+        let pId = PackedItemId(module: n1.litId, item: tree[n2].soperand)
         let itemId = translateId(pId, c.g.packed, c.thisModule, c.g.config)
-        if searchForeignSym(c, itemId, tree.nodes[i].info):
+        if searchForeignSym(c, itemId, tree[i].info):
           return itemId
     else: discard
   return EmptyItemId
@@ -73,36 +84,38 @@ proc isDecl(tree: PackedTree; n: NodePos): bool =
   const declarativeNodes = procDefs + {nkMacroDef, nkTemplateDef,
     nkLetSection, nkVarSection, nkUsingStmt, nkConstSection, nkTypeSection,
     nkIdentDefs, nkEnumTy, nkVarTuple}
-  result = n.int >= 0 and tree[n.int].kind in declarativeNodes
+  result = n.int >= 0 and tree[n].kind in declarativeNodes
 
 proc usage(c: var NavContext; info: PackedLineInfo; isDecl: bool) =
+  let (fileId, line, col) = unpack(c.g.packed[c.thisModule].fromDisk.man, info)
   var m = ""
-  var file = c.g.packed[c.thisModule].fromDisk.strings[info.file]
+  var file = c.g.packed[c.thisModule].fromDisk.strings[fileId]
   if c.outputSep == ' ':
     file = os.extractFilename file
-  toLocation(m, file, info.line.int, info.col.int + ColOffset)
+  toLocation(m, file, line, col + ColOffset)
   if not c.alreadyEmitted.containsOrIncl(m):
     msgWriteln c.g.config, (if isDecl: "def" else: "usage") & c.outputSep & m
 
 proc list(c: var NavContext; tree: PackedTree; sym: ItemId) =
-  for i in 0..high(tree.nodes):
-    case tree.nodes[i].kind
+  for i in 0..<len(tree):
+    let i = NodePos(i)
+    case tree[i].kind
     of nkSym:
-      let item = tree.nodes[i].operand
+      let item = tree[i].soperand
       if sym.item == item and sym.module == c.thisModule:
-        usage(c, tree.nodes[i].info, isDecl(tree, parent(NodePos i)))
+        usage(c, tree[i].info, isDecl(tree, parent(i)))
     of nkModuleRef:
-      let (n1, n2) = sons2(tree, NodePos i)
-      assert n1.kind == nkInt32Lit
-      assert n2.kind == nkInt32Lit
-      let pId = PackedItemId(module: n1.litId, item: tree.nodes[n2.int].operand)
+      let (n1, n2) = sons2(tree, i)
+      assert n1.kind == nkNone
+      assert n2.kind == nkNone
+      let pId = PackedItemId(module: n1.litId, item: tree[n2].soperand)
       let itemId = translateId(pId, c.g.packed, c.thisModule, c.g.config)
       if itemId.item == sym.item and sym.module == itemId.module:
-        usage(c, tree.nodes[i].info, isDecl(tree, parent(NodePos i)))
+        usage(c, tree[i].info, isDecl(tree, parent(i)))
     else: discard
 
 proc searchForIncludeFile(g: ModuleGraph; fullPath: string): int =
-  for i in 0..high(g.packed):
+  for i in 0..<len(g.packed):
     for k in 1..high(g.packed[i].fromDisk.includes):
       # we start from 1 because the first "include" file is
       # the module's filename.
@@ -134,7 +147,7 @@ proc nav(g: ModuleGraph) =
   var c = NavContext(
     g: g,
     thisModule: int32 mid,
-    trackPos: PackedLineInfo(line: unpacked.line, col: unpacked.col, file: fileId),
+    trackPos: UnpackedLineInfo(line: unpacked.line.int, col: unpacked.col.int, file: fileId),
     outputSep: if isDefined(g.config, "nimIcNavigatorTests"): ' ' else: '\t'
   )
   var symId = search(c, g.packed[mid].fromDisk.topLevel)
@@ -145,7 +158,7 @@ proc nav(g: ModuleGraph) =
     localError(g.config, unpacked, "no symbol at this position")
     return
 
-  for i in 0..high(g.packed):
+  for i in 0..<len(g.packed):
     # case statement here to enforce exhaustive checks.
     case g.packed[i].status
     of undefined:
@@ -162,7 +175,7 @@ proc navUsages*(g: ModuleGraph) = nav(g)
 proc navDefusages*(g: ModuleGraph) = nav(g)
 
 proc writeRodFiles*(g: ModuleGraph) =
-  for i in 0..high(g.packed):
+  for i in 0..<len(g.packed):
     case g.packed[i].status
     of undefined, loading, stored, loaded:
       discard "nothing to do"

compiler/ic/packed_ast.nim

@@ -12,10 +12,12 @@
 ## use this representation directly in all the transformations,
 ## it is superior.
 
-import hashes, tables, strtabs
-import bitabs
+import std/[hashes, tables, strtabs]
+import bitabs, rodfiles
 import ".." / [ast, options]
 
+import iclineinfos
+
 when defined(nimPreviewSlimSystem):
   import std/assertions
 
@@ -31,17 +33,12 @@ type
     item*: int32         # same as the in-memory representation
 
 const
-  nilItemId* = PackedItemId(module: LitId(0), item: -1.int32)
+  nilItemId* = PackedItemId(module: LitId(0), item: 0.int32)
 
 const
   emptyNodeId* = NodeId(-1)
 
 type
-  PackedLineInfo* = object
-    line*: uint16
-    col*: int16
-    file*: LitId
-
   PackedLib* = object
     kind*: TLibKind
     generated*: bool
@@ -50,6 +47,7 @@ type
     path*: NodeId
 
   PackedSym* = object
+    id*: int32
     kind*: TSymKind
     name*: LitId
     typ*: PackedItemId
@@ -71,8 +69,10 @@ type
     when hasFFI:
       cname*: LitId
     constraint*: NodeId
+    instantiatedFrom*: PackedItemId
 
   PackedType* = object
+    id*: int32
     kind*: TTypeKind
     callConv*: TCallingConvention
     #nodekind*: TNodeKind
@@ -89,23 +89,35 @@ type
     typeInst*: PackedItemId
     nonUniqueId*: int32
 
-  PackedNode* = object     # 28 bytes
-    kind*: TNodeKind
-    flags*: TNodeFlags
-    operand*: int32  # for kind in {nkSym, nkSymDef}: SymId
-                     # for kind in {nkStrLit, nkIdent, nkNumberLit}: LitId
-                     # for kind in nkInt32Lit: direct value
-                     # for non-atom kinds: the number of nodes (for easy skipping)
-    typeId*: PackedItemId
+  PackedNode* = object     # 8 bytes
+    x: uint32
     info*: PackedLineInfo
 
   PackedTree* = object ## usually represents a full Nim module
-    nodes*: seq[PackedNode]
+    nodes: seq[PackedNode]
+    withFlags: seq[(int32, TNodeFlags)]
+    withTypes: seq[(int32, PackedItemId)]
 
   PackedInstantiation* = object
     key*, sym*: PackedItemId
     concreteTypes*: seq[PackedItemId]
 
+const
+  NodeKindBits = 8'u32
+  NodeKindMask = (1'u32 shl NodeKindBits) - 1'u32
+
+template kind*(n: PackedNode): TNodeKind = TNodeKind(n.x and NodeKindMask)
+template uoperand*(n: PackedNode): uint32 = (n.x shr NodeKindBits)
+template soperand*(n: PackedNode): int32 = int32(uoperand(n))
+
+template toX(k: TNodeKind; operand: uint32): uint32 =
+  uint32(k) or (operand shl NodeKindBits)
+
+template toX(k: TNodeKind; operand: LitId): uint32 =
+  uint32(k) or (operand.uint32 shl NodeKindBits)
+
+template typeId*(n: PackedNode): PackedItemId = n.typ
+
 proc `==`*(a, b: SymId): bool {.borrow.}
 proc hash*(a: SymId): Hash {.borrow.}
 
@@ -114,71 +126,35 @@ proc `==`*(a, b: NodePos): bool {.borrow.}
 proc `==`*(a, b: NodeId): bool {.borrow.}
 
 proc newTreeFrom*(old: PackedTree): PackedTree =
-  result.nodes = @[]
+  result = PackedTree(nodes: @[])
   when false: result.sh = old.sh
 
-when false:
-  proc declareSym*(tree: var PackedTree; kind: TSymKind;
-                  name: LitId; info: PackedLineInfo): SymId =
-    result = SymId(tree.sh.syms.len)
-    tree.sh.syms.add PackedSym(kind: kind, name: name, flags: {}, magic: mNone, info: info)
-
-  proc litIdFromName*(tree: PackedTree; name: string): LitId =
-    result = tree.sh.strings.getOrIncl(name)
-
-  proc add*(tree: var PackedTree; kind: TNodeKind; token: string; info: PackedLineInfo) =
-    tree.nodes.add PackedNode(kind: kind, info: info,
-                              operand: int32 getOrIncl(tree.sh.strings, token))
-
-  proc add*(tree: var PackedTree; kind: TNodeKind; info: PackedLineInfo) =
-    tree.nodes.add PackedNode(kind: kind, operand: 0, info: info)
-
-proc throwAwayLastNode*(tree: var PackedTree) =
-  tree.nodes.setLen(tree.nodes.len-1)
-
 proc addIdent*(tree: var PackedTree; s: LitId; info: PackedLineInfo) =
-  tree.nodes.add PackedNode(kind: nkIdent, operand: int32(s), info: info)
+  tree.nodes.add PackedNode(x: toX(nkIdent, uint32(s)), info: info)
 
 proc addSym*(tree: var PackedTree; s: int32; info: PackedLineInfo) =
-  tree.nodes.add PackedNode(kind: nkSym, operand: s, info: info)
-
-proc addModuleId*(tree: var PackedTree; s: ModuleId; info: PackedLineInfo) =
-  tree.nodes.add PackedNode(kind: nkInt32Lit, operand: int32(s), info: info)
+  tree.nodes.add PackedNode(x: toX(nkSym, cast[uint32](s)), info: info)
 
 proc addSymDef*(tree: var PackedTree; s: SymId; info: PackedLineInfo) =
-  tree.nodes.add PackedNode(kind: nkSym, operand: int32(s), info: info)
+  tree.nodes.add PackedNode(x: toX(nkSym, cast[uint32](s)), info: info)
 
 proc isAtom*(tree: PackedTree; pos: int): bool {.inline.} = tree.nodes[pos].kind <= nkNilLit
 
-proc copyTree*(dest: var PackedTree; tree: PackedTree; n: NodePos) =
-  # and this is why the IR is superior. We can copy subtrees
-  # via a linear scan.
-  let pos = n.int
-  let L = if isAtom(tree, pos): 1 else: tree.nodes[pos].operand
-  let d = dest.nodes.len
-  dest.nodes.setLen(d + L)
-  for i in 0..<L:
-    dest.nodes[d+i] = tree.nodes[pos+i]
-
-when false:
-  proc copySym*(dest: var PackedTree; tree: PackedTree; s: SymId): SymId =
-    result = SymId(dest.sh.syms.len)
-    assert int(s) < tree.sh.syms.len
-    let oldSym = tree.sh.syms[s.int]
-    dest.sh.syms.add oldSym
-
 type
   PatchPos = distinct int
 
-when false:
-  proc prepare*(tree: var PackedTree; kind: TNodeKind; info: PackedLineInfo): PatchPos =
-    result = PatchPos tree.nodes.len
-    tree.nodes.add PackedNode(kind: kind, operand: 0, info: info)
+proc addNode*(t: var PackedTree; kind: TNodeKind; operand: int32;
+              typeId: PackedItemId = nilItemId; info: PackedLineInfo;
+              flags: TNodeFlags = {}) =
+  t.nodes.add PackedNode(x: toX(kind, cast[uint32](operand)), info: info)
+  if flags != {}:
+    t.withFlags.add (t.nodes.len.int32 - 1, flags)
+  if typeId != nilItemId:
+    t.withTypes.add (t.nodes.len.int32 - 1, typeId)
 
 proc prepare*(tree: var PackedTree; kind: TNodeKind; flags: TNodeFlags; typeId: PackedItemId; info: PackedLineInfo): PatchPos =
   result = PatchPos tree.nodes.len
-  tree.nodes.add PackedNode(kind: kind, flags: flags, operand: 0, info: info,
-                            typeId: typeId)
+  tree.addNode(kind = kind, flags = flags, operand = 0, info = info, typeId = typeId)
 
 proc prepare*(dest: var PackedTree; source: PackedTree; sourcePos: NodePos): PatchPos =
   result = PatchPos dest.nodes.len
@@ -186,26 +162,30 @@ proc prepare*(dest: var PackedTree; source: PackedTree; sourcePos: NodePos): Pat
 
 proc patch*(tree: var PackedTree; pos: PatchPos) =
   let pos = pos.int
-  assert tree.nodes[pos].kind > nkNilLit
+  let k = tree.nodes[pos].kind
+  assert k > nkNilLit
   let distance = int32(tree.nodes.len - pos)
-  tree.nodes[pos].operand = distance
+  assert distance > 0
+  tree.nodes[pos].x = toX(k, cast[uint32](distance))
 
 proc len*(tree: PackedTree): int {.inline.} = tree.nodes.len
 
-proc `[]`*(tree: PackedTree; i: int): lent PackedNode {.inline.} =
-  tree.nodes[i]
+proc `[]`*(tree: PackedTree; i: NodePos): lent PackedNode {.inline.} =
+  tree.nodes[i.int]
+
+template rawSpan(n: PackedNode): int = int(uoperand(n))
 
 proc nextChild(tree: PackedTree; pos: var int) {.inline.} =
   if tree.nodes[pos].kind > nkNilLit:
-    assert tree.nodes[pos].operand > 0
-    inc pos, tree.nodes[pos].operand
+    assert tree.nodes[pos].uoperand > 0
+    inc pos, tree.nodes[pos].rawSpan
   else:
     inc pos
 
 iterator sonsReadonly*(tree: PackedTree; n: NodePos): NodePos =
   var pos = n.int
   assert tree.nodes[pos].kind > nkNilLit
-  let last = pos + tree.nodes[pos].operand
+  let last = pos + tree.nodes[pos].rawSpan
   inc pos
   while pos < last:
     yield NodePos pos
@@ -226,7 +206,7 @@ iterator isons*(dest: var PackedTree; tree: PackedTree;
 iterator sonsFrom1*(tree: PackedTree; n: NodePos): NodePos =
   var pos = n.int
   assert tree.nodes[pos].kind > nkNilLit
-  let last = pos + tree.nodes[pos].operand
+  let last = pos + tree.nodes[pos].rawSpan
   inc pos
   if pos < last:
     nextChild tree, pos
@@ -240,7 +220,7 @@ iterator sonsWithoutLast2*(tree: PackedTree; n: NodePos): NodePos =
     inc count
   var pos = n.int
   assert tree.nodes[pos].kind > nkNilLit
-  let last = pos + tree.nodes[pos].operand
+  let last = pos + tree.nodes[pos].rawSpan
   inc pos
   while pos < last and count > 2:
     yield NodePos pos
@@ -250,7 +230,7 @@ iterator sonsWithoutLast2*(tree: PackedTree; n: NodePos): NodePos =
 proc parentImpl(tree: PackedTree; n: NodePos): NodePos =
   # finding the parent of a node is rather easy:
   var pos = n.int - 1
-  while pos >= 0 and (isAtom(tree, pos) or (pos + tree.nodes[pos].operand - 1 < n.int)):
+  while pos >= 0 and (isAtom(tree, pos) or (pos + tree.nodes[pos].rawSpan - 1 < n.int)):
     dec pos
   #assert pos >= 0, "node has no parent"
   result = NodePos(pos)
@@ -276,20 +256,32 @@ proc firstSon*(tree: PackedTree; n: NodePos): NodePos {.inline.} =
 proc kind*(tree: PackedTree; n: NodePos): TNodeKind {.inline.} =
   tree.nodes[n.int].kind
 proc litId*(tree: PackedTree; n: NodePos): LitId {.inline.} =
-  LitId tree.nodes[n.int].operand
+  LitId tree.nodes[n.int].uoperand
 proc info*(tree: PackedTree; n: NodePos): PackedLineInfo {.inline.} =
   tree.nodes[n.int].info
 
-template typ*(n: NodePos): PackedItemId =
-  tree.nodes[n.int].typeId
-template flags*(n: NodePos): TNodeFlags =
-  tree.nodes[n.int].flags
+proc findType*(tree: PackedTree; n: NodePos): PackedItemId =
+  for x in tree.withTypes:
+    if x[0] == int32(n): return x[1]
+    if x[0] > int32(n): return nilItemId
+  return nilItemId
 
-template operand*(n: NodePos): int32 =
-  tree.nodes[n.int].operand
+proc findFlags*(tree: PackedTree; n: NodePos): TNodeFlags =
+  for x in tree.withFlags:
+    if x[0] == int32(n): return x[1]
+    if x[0] > int32(n): return {}
+  return {}
+
+template typ*(n: NodePos): PackedItemId =
+  tree.findType(n)
+template flags*(n: NodePos): TNodeFlags =
+  tree.findFlags(n)
+
+template uoperand*(n: NodePos): uint32 =
+  tree.nodes[n.int].uoperand
 
 proc span*(tree: PackedTree; pos: int): int {.inline.} =
-  if isAtom(tree, pos): 1 else: tree.nodes[pos].operand
+  if isAtom(tree, pos): 1 else: tree.nodes[pos].rawSpan
 
 proc sons2*(tree: PackedTree; n: NodePos): (NodePos, NodePos) =
   assert(not isAtom(tree, n.int))
@@ -305,6 +297,7 @@ proc sons3*(tree: PackedTree; n: NodePos): (NodePos, NodePos, NodePos) =
   result = (NodePos a, NodePos b, NodePos c)
 
 proc ithSon*(tree: PackedTree; n: NodePos; i: int): NodePos =
+  result = default(NodePos)
   if tree.nodes[n.int].kind > nkNilLit:
     var count = 0
     for child in sonsReadonly(tree, n):
@@ -318,64 +311,28 @@ when false:
 
 template kind*(n: NodePos): TNodeKind = tree.nodes[n.int].kind
 template info*(n: NodePos): PackedLineInfo = tree.nodes[n.int].info
-template litId*(n: NodePos): LitId = LitId tree.nodes[n.int].operand
+template litId*(n: NodePos): LitId = LitId tree.nodes[n.int].uoperand
 
-template symId*(n: NodePos): SymId = SymId tree.nodes[n.int].operand
+template symId*(n: NodePos): SymId = SymId tree.nodes[n.int].soperand
 
 proc firstSon*(n: NodePos): NodePos {.inline.} = NodePos(n.int+1)
 
-when false:
-  # xxx `nkStrLit` or `nkStrLit..nkTripleStrLit:` below?
-  proc strLit*(tree: PackedTree; n: NodePos): lent string =
-    assert n.kind == nkStrLit
-    result = tree.sh.strings[LitId tree.nodes[n.int].operand]
-
-  proc strVal*(tree: PackedTree; n: NodePos): string =
-    assert n.kind == nkStrLit
-    result = tree.sh.strings[LitId tree.nodes[n.int].operand]
-    #result = cookedStrLit(raw)
-
-  proc filenameVal*(tree: PackedTree; n: NodePos): string =
-    case n.kind
-    of nkStrLit:
-      result = strVal(tree, n)
-    of nkIdent:
-      result = tree.sh.strings[n.litId]
-    of nkSym:
-      result = tree.sh.strings[tree.sh.syms[int n.symId].name]
-    else:
-      result = ""
-
-  proc identAsStr*(tree: PackedTree; n: NodePos): lent string =
-    assert n.kind == nkIdent
-    result = tree.sh.strings[LitId tree.nodes[n.int].operand]
-
 const
   externIntLit* = {nkCharLit,
     nkIntLit,
     nkInt8Lit,
     nkInt16Lit,
+    nkInt32Lit,
     nkInt64Lit,
     nkUIntLit,
     nkUInt8Lit,
     nkUInt16Lit,
     nkUInt32Lit,
-    nkUInt64Lit} # nkInt32Lit is missing by design!
+    nkUInt64Lit}
 
-  externSIntLit* = {nkIntLit, nkInt8Lit, nkInt16Lit, nkInt64Lit}
+  externSIntLit* = {nkIntLit, nkInt8Lit, nkInt16Lit, nkInt32Lit, nkInt64Lit}
   externUIntLit* = {nkUIntLit, nkUInt8Lit, nkUInt16Lit, nkUInt32Lit, nkUInt64Lit}
-  directIntLit* = nkInt32Lit
-
-when false:
-  proc identIdImpl(tree: PackedTree; n: NodePos): LitId =
-    if n.kind == nkIdent:
-      result = n.litId
-    elif n.kind == nkSym:
-      result = tree.sh.syms[int n.symId].name
-    else:
-      result = LitId(0)
-
-  template identId*(n: NodePos): LitId = identIdImpl(tree, n)
+  directIntLit* = nkNone
 
 template copyInto*(dest, n, body) =
   let patchPos = prepare(dest, tree, n)
@@ -387,28 +344,8 @@ template copyIntoKind*(dest, kind, info, body) =
   body
   patch dest, patchPos
 
-when false:
-  proc hasPragma*(tree: PackedTree; n: NodePos; pragma: string): bool =
-    let litId = tree.sh.strings.getKeyId(pragma)
-    if litId == LitId(0):
-      return false
-    assert n.kind == nkPragma
-    for ch0 in sonsReadonly(tree, n):
-      if ch0.kind == nkExprColonExpr:
-        if ch0.firstSon.identId == litId:
-          return true
-      elif ch0.identId == litId:
-        return true
-
 proc getNodeId*(tree: PackedTree): NodeId {.inline.} = NodeId tree.nodes.len
 
-when false:
-  proc produceError*(dest: var PackedTree; tree: PackedTree; n: NodePos; msg: string) =
-    let patchPos = prepare(dest, nkError, n.info)
-    dest.add nkStrLit, msg, n.info
-    copyTree(dest, tree, n)
-    patch dest, patchPos
-
 iterator allNodes*(tree: PackedTree): NodePos =
   var p = 0
   while p < tree.len:
@@ -418,3 +355,13 @@ iterator allNodes*(tree: PackedTree): NodePos =
 
 proc toPackedItemId*(item: int32): PackedItemId {.inline.} =
   PackedItemId(module: LitId(0), item: item)
+
+proc load*(f: var RodFile; t: var PackedTree) =
+  loadSeq f, t.nodes
+  loadSeq f, t.withFlags
+  loadSeq f, t.withTypes
+
+proc store*(f: var RodFile; t: PackedTree) =
+  storeSeq f, t.nodes
+  storeSeq f, t.withFlags
+  storeSeq f, t.withTypes

compiler/ic/replayer.nim

@@ -14,7 +14,7 @@
 import ".." / [ast, modulegraphs, trees, extccomp, btrees,
   msgs, lineinfos, pathutils, options, cgmeth]
 
-import tables
+import std/tables
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
@@ -103,6 +103,17 @@ proc replayBackendProcs*(g: ModuleGraph; module: int) =
     let symId = FullId(module: tmp.module, packed: it[1])
     g.enumToStringProcs[key] = LazySym(id: symId, sym: nil)
 
+  for it in mitems(g.packed[module].fromDisk.methodsPerType):
+    let key = translateId(it[0], g.packed, module, g.config)
+    let tmp = translateId(it[1], g.packed, module, g.config)
+    let symId = FullId(module: tmp.module, packed: it[1])
+    g.methodsPerType.mgetOrPut(key, @[]).add LazySym(id: symId, sym: nil)
+
+  for it in mitems(g.packed[module].fromDisk.dispatchers):
+    let tmp = translateId(it, g.packed, module, g.config)
+    let symId = FullId(module: tmp.module, packed: it)
+    g.dispatchers.add LazySym(id: symId, sym: nil)
+
 proc replayGenericCacheInformation*(g: ModuleGraph; module: int) =
   ## We remember the generic instantiations a module performed
   ## in order to to avoid the code bloat that generic code tends
@@ -127,12 +138,12 @@ proc replayGenericCacheInformation*(g: ModuleGraph; module: int) =
       module: module, sym: FullId(module: sym.module, packed: it.sym),
       concreteTypes: concreteTypes, inst: nil)
 
-  for it in mitems(g.packed[module].fromDisk.methodsPerType):
+  for it in mitems(g.packed[module].fromDisk.methodsPerGenericType):
     let key = translateId(it[0], g.packed, module, g.config)
     let col = it[1]
     let tmp = translateId(it[2], g.packed, module, g.config)
     let symId = FullId(module: tmp.module, packed: it[2])
-    g.methodsPerType.mgetOrPut(key, @[]).add (col, LazySym(id: symId, sym: nil))
+    g.methodsPerGenericType.mgetOrPut(key, @[]).add (col, LazySym(id: symId, sym: nil))
 
   replayBackendProcs(g, module)
 

compiler/ic/rodfiles.nim

@@ -14,11 +14,13 @@
 ##     compiler works and less a storage format, you're probably looking for
 ##     the `ic` or `packed_ast` modules to understand the logical format.
 
-from typetraits import supportsCopyMem
+from std/typetraits import supportsCopyMem
 
 when defined(nimPreviewSlimSystem):
   import std/[syncio, assertions]
 
+import std / tables
+
 ## Overview
 ## ========
 ## `RodFile` represents a Rod File (versioned binary format), and the
@@ -92,11 +94,16 @@ type
     typeInstCacheSection
     procInstCacheSection
     attachedOpsSection
-    methodsPerTypeSection
+    methodsPerGenericTypeSection
     enumToStringProcsSection
+    methodsPerTypeSection
+    dispatchersSection
     typeInfoSection  # required by the backend
     backendFlagsSection
     aliveSymsSection # beware, this is stored in a `.alivesyms` file.
+    sideChannelSection
+    namespaceSection
+    symnamesSection
 
   RodFileError* = enum
     ok, tooBig, cannotOpen, ioFailure, wrongHeader, wrongSection, configMismatch,
@@ -109,8 +116,8 @@ type
                        # better than exceptions.
 
 const
-  RodVersion = 1
-  cookie = [byte(0), byte('R'), byte('O'), byte('D'),
+  RodVersion = 2
+  defaultCookie = [byte(0), byte('R'), byte('O'), byte('D'),
             byte(sizeof(int)*8), byte(system.cpuEndian), byte(0), byte(RodVersion)]
 
 proc setError(f: var RodFile; err: RodFileError) {.inline.} =
@@ -165,6 +172,18 @@ proc storeSeq*[T](f: var RodFile; s: seq[T]) =
     for i in 0..<s.len:
       storePrim(f, s[i])
 
+proc storeOrderedTable*[K, T](f: var RodFile; s: OrderedTable[K, T]) =
+  if f.err != ok: return
+  if s.len >= high(int32):
+    setError f, tooBig
+    return
+  var lenPrefix = int32(s.len)
+  if writeBuffer(f.f, addr lenPrefix, sizeof(lenPrefix)) != sizeof(lenPrefix):
+    setError f, ioFailure
+  else:
+    for _, v in s:
+      storePrim(f, v)
+
 proc loadPrim*(f: var RodFile; s: var string) =
   ## Read a string, the length was stored as a prefix
   if f.err != ok: return
@@ -206,16 +225,29 @@ proc loadSeq*[T](f: var RodFile; s: var seq[T]) =
     for i in 0..<lenPrefix:
       loadPrim(f, s[i])
 
-proc storeHeader*(f: var RodFile) =
+proc loadOrderedTable*[K, T](f: var RodFile; s: var OrderedTable[K, T]) =
+  ## `T` must be compatible with `copyMem`, see `loadPrim`
+  if f.err != ok: return
+  var lenPrefix = int32(0)
+  if readBuffer(f.f, addr lenPrefix, sizeof(lenPrefix)) != sizeof(lenPrefix):
+    setError f, ioFailure
+  else:
+    s = initOrderedTable[K, T](lenPrefix)
+    for i in 0..<lenPrefix:
+      var x = default T
+      loadPrim(f, x)
+      s[x.id] = x
+
+proc storeHeader*(f: var RodFile; cookie = defaultCookie) =
   ## stores the header which is described by `cookie`.
   if f.err != ok: return
   if f.f.writeBytes(cookie, 0, cookie.len) != cookie.len:
     setError f, ioFailure
 
-proc loadHeader*(f: var RodFile) =
+proc loadHeader*(f: var RodFile; cookie = defaultCookie) =
   ## Loads the header which is described by `cookie`.
   if f.err != ok: return
-  var thisCookie: array[cookie.len, byte]
+  var thisCookie: array[cookie.len, byte] = default(array[cookie.len, byte])
   if f.f.readBytes(thisCookie, 0, thisCookie.len) != thisCookie.len:
     setError f, ioFailure
   elif thisCookie != cookie:
@@ -231,13 +263,14 @@ proc storeSection*(f: var RodFile; s: RodSection) =
 proc loadSection*(f: var RodFile; expected: RodSection) =
   ## read the bytes value of s, sets and error if the section is incorrect.
   if f.err != ok: return
-  var s: RodSection
+  var s: RodSection = default(RodSection)
   loadPrim(f, s)
   if expected != s and f.err == ok:
     setError f, wrongSection
 
 proc create*(filename: string): RodFile =
   ## create the file and open it for writing
+  result = default(RodFile)
   if not open(result.f, filename, fmWrite):
     setError result, cannotOpen
 
@@ -245,5 +278,6 @@ proc close*(f: var RodFile) = close(f.f)
 
 proc open*(filename: string): RodFile =
   ## open the file for reading
+  result = default(RodFile)
   if not open(result.f, filename, fmRead):
     setError result, cannotOpen

compiler/idents.nim

@@ -11,8 +11,8 @@
 # An identifier is a shared immutable string that can be compared by its
 # id. This module is essential for the compiler's performance.
 
-import
-  hashes, wordrecg
+import wordrecg
+import std/hashes
 
 when defined(nimPreviewSlimSystem):
   import std/assertions

compiler/importer.nim

@@ -10,10 +10,12 @@
 ## This module implements the symbol importing mechanism.
 
 import
-  intsets, ast, astalgo, msgs, options, idents, lookups,
-  semdata, modulepaths, sigmatch, lineinfos, sets,
-  modulegraphs, wordrecg, tables
-from strutils import `%`
+  ast, astalgo, msgs, options, idents, lookups,
+  semdata, modulepaths, sigmatch, lineinfos,
+  modulegraphs, wordrecg
+from std/strutils import `%`, startsWith
+from std/sequtils import addUnique
+import std/[sets, tables, intsets]
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
@@ -113,6 +115,7 @@ proc rawImportSymbol(c: PContext, s, origin: PSym; importSet: var IntSet) =
 
 proc splitPragmas(c: PContext, n: PNode): (PNode, seq[TSpecialWord]) =
   template bail = globalError(c.config, n.info, "invalid pragma")
+  result = (nil, @[])
   if n.kind == nkPragmaExpr:
     if n.len == 2 and n[1].kind == nkPragma:
       result[0] = n[0]
@@ -141,7 +144,7 @@ proc importSymbol(c: PContext, n: PNode, fromMod: PSym; importSet: var IntSet) =
     # for an enumeration we have to add all identifiers
     if multiImport:
       # for a overloadable syms add all overloaded routines
-      var it: ModuleIter
+      var it: ModuleIter = default(ModuleIter)
       var e = initModuleIter(it, c.graph, fromMod, s.name)
       while e != nil:
         if e.name.id != s.name.id: internalError(c.config, n.info, "importSymbol: 3")
@@ -228,11 +231,6 @@ proc importForwarded(c: PContext, n: PNode, exceptSet: IntSet; fromMod: PSym; im
     for i in 0..n.safeLen-1:
       importForwarded(c, n[i], exceptSet, fromMod, importSet)
 
-proc addUnique[T](x: var seq[T], y: sink T) {.noSideEffect.} =
-  for i in 0..high(x):
-    if x[i] == y: return
-  x.add y
-    
 proc importModuleAs(c: PContext; n: PNode, realModule: PSym, importHidden: bool): PSym =
   result = realModule
   template createModuleAliasImpl(ident): untyped =
@@ -248,12 +246,14 @@ proc importModuleAs(c: PContext; n: PNode, realModule: PSym, importHidden: bool)
     result = createModuleAliasImpl(realModule.name)
   if importHidden:
     result.options.incl optImportHidden
-  c.unusedImports.add((result, n.info))
+  let moduleIdent = if n.kind == nkInfix: n[^1] else: n
+  c.unusedImports.add((result, moduleIdent.info))
   c.importModuleMap[result.id] = realModule.id
   c.importModuleLookup.mgetOrPut(result.name.id, @[]).addUnique realModule.id
 
 proc transformImportAs(c: PContext; n: PNode): tuple[node: PNode, importHidden: bool] =
-  var ret: typeof(result)
+  result = (nil, false)
+  var ret = default(typeof(result))
   proc processPragma(n2: PNode): PNode =
     let (result2, kws) = splitPragmas(c, n2)
     result = result2
@@ -304,6 +304,10 @@ proc myImportModule(c: PContext, n: var PNode, importStmtResult: PNode): PSym =
       var prefix = ""
       if realModule.constraint != nil: prefix = realModule.constraint.strVal & "; "
       message(c.config, n.info, warnDeprecated, prefix & realModule.name.s & " is deprecated")
+    let moduleName = getModuleName(c.config, n)
+    if belongsToStdlib(c.graph, result) and not startsWith(moduleName, stdPrefix) and
+        not startsWith(moduleName, "system/") and not startsWith(moduleName, "packages/"):
+      message(c.config, n.info, warnStdPrefix, realModule.name.s)
 
     proc suggestMod(n: PNode; s: PSym) =
       if n.kind == nkImportAs:
@@ -315,8 +319,11 @@ proc myImportModule(c: PContext, n: var PNode, importStmtResult: PNode): PSym =
     suggestMod(n, result)
     importStmtResult.add newSymNode(result, n.info)
     #newStrNode(toFullPath(c.config, f), n.info)
+  else:
+    result = nil
 
 proc afterImport(c: PContext, m: PSym) =
+  if isCachedModule(c.graph, m): return
   # fixes bug #17510, for re-exported symbols
   let realModuleId = c.importModuleMap[m.id]
   for s in allSyms(c.graph, m):
@@ -352,11 +359,9 @@ proc evalImport*(c: PContext, n: PNode): PNode =
           imp[lastPos] = x[1]
           impAs[1] = imp
           impAs[2] = x[2]
-          impAs.info = x[2].info
           impMod(c, impAs, result)
         else:
           imp[lastPos] = x
-          imp.info = x.info
           impMod(c, imp, result)
     else:
       impMod(c, it, result)

compiler/injectdestructors.nim

@@ -14,11 +14,13 @@
 ## See doc/destructors.rst for a spec of the implemented rewrite rules
 
 import
-  intsets, strtabs, ast, astalgo, msgs, renderer, magicsys, types, idents,
-  strutils, options, lowerings, tables, modulegraphs,
+  ast, astalgo, msgs, renderer, magicsys, types, idents,
+  options, lowerings, modulegraphs,
   lineinfos, parampatterns, sighashes, liftdestructors, optimizer,
   varpartitions, aliasanalysis, dfa, wordrecg
 
+import std/[strtabs, tables, strutils, intsets]
+
 when defined(nimPreviewSlimSystem):
   import std/assertions
 
@@ -210,15 +212,17 @@ proc checkForErrorPragma(c: Con; t: PType; ri: PNode; opname: string; inferredFr
       m.add " a 'sink' parameter"
   m.add "; routine: "
   m.add c.owner.name.s
+  #m.add "\n\n"
+  #m.add renderTree(c.body, {renderIds})
   localError(c.graph.config, ri.info, errGenerated, m)
 
 proc makePtrType(c: var Con, baseType: PType): PType =
-  result = newType(tyPtr, nextTypeId c.idgen, c.owner)
+  result = newType(tyPtr, c.idgen, c.owner)
   addSonSkipIntLit(result, baseType, c.idgen)
 
 proc genOp(c: var Con; op: PSym; dest: PNode): PNode =
   var addrExp: PNode
-  if op.typ != nil and op.typ.len > 1 and op.typ[1].kind != tyVar:
+  if op.typ != nil and op.typ.signatureLen > 1 and op.typ.firstParamType.kind != tyVar:
     addrExp = dest
   else:
     addrExp = newNodeIT(nkHiddenAddr, dest.info, makePtrType(c, dest.typ))
@@ -313,8 +317,9 @@ proc isCriticalLink(dest: PNode): bool {.inline.} =
   ]#
   result = dest.kind != nkSym
 
-proc finishCopy(c: var Con; result, dest: PNode; isFromSink: bool) =
-  if c.graph.config.selectedGC == gcOrc:
+proc finishCopy(c: var Con; result, dest: PNode; flags: set[MoveOrCopyFlag]; isFromSink: bool) =
+  if c.graph.config.selectedGC == gcOrc and IsExplicitSink notin flags:
+    # add cyclic flag, but not to sink calls, which IsExplicitSink generates
     let t = dest.typ.skipTypes(tyUserTypeClasses + {tyGenericInst, tyAlias, tySink, tyDistinct})
     if cyclicType(c.graph, t):
       result.add boolLit(c.graph, result.info, isFromSink or isCriticalLink(dest))
@@ -327,7 +332,7 @@ proc genMarkCyclic(c: var Con; result, dest: PNode) =
         result.add callCodegenProc(c.graph, "nimMarkCyclic", dest.info, dest)
       else:
         let xenv = genBuiltin(c.graph, c.idgen, mAccessEnv, "accessEnv", dest)
-        xenv.typ = getSysType(c.graph, dest.info, tyPointer)
+        xenv.typ() = getSysType(c.graph, dest.info, tyPointer)
         result.add callCodegenProc(c.graph, "nimMarkCyclic", dest.info, xenv)
 
 proc genCopyNoCheck(c: var Con; dest, ri: PNode; a: TTypeAttachedOp): PNode =
@@ -403,7 +408,7 @@ proc genWasMoved(c: var Con, n: PNode): PNode =
 proc genDefaultCall(t: PType; c: Con; info: TLineInfo): PNode =
   result = newNodeI(nkCall, info)
   result.add(newSymNode(createMagic(c.graph, c.idgen, "default", mDefault)))
-  result.typ = t
+  result.typ() = t
 
 proc destructiveMoveVar(n: PNode; c: var Con; s: var Scope): PNode =
   # generate: (let tmp = v; reset(v); tmp)
@@ -438,6 +443,7 @@ proc destructiveMoveVar(n: PNode; c: var Con; s: var Scope): PNode =
 proc isCapturedVar(n: PNode): bool =
   let root = getRoot(n)
   if root != nil: result = root.name.s[0] == ':'
+  else: result = false
 
 proc passCopyToSink(n: PNode; c: var Con; s: var Scope): PNode =
   result = newNodeIT(nkStmtListExpr, n.info, n.typ)
@@ -459,7 +465,7 @@ proc passCopyToSink(n: PNode; c: var Con; s: var Scope): PNode =
       var newCall = newTreeIT(nkCall, src.info, src.typ,
             newSymNode(op),
             src)
-      c.finishCopy(newCall, n, isFromSink = true)
+      c.finishCopy(newCall, n, {}, isFromSink = true)
       result.add newTreeI(nkFastAsgn,
           src.info, tmp,
           newCall
@@ -468,7 +474,7 @@ proc passCopyToSink(n: PNode; c: var Con; s: var Scope): PNode =
       result.add c.genWasMoved(tmp)
       var m = c.genCopy(tmp, n, {})
       m.add p(n, c, s, normal)
-      c.finishCopy(m, n, isFromSink = true)
+      c.finishCopy(m, n, {}, isFromSink = true)
       result.add m
     if isLValue(n) and not isCapturedVar(n) and nTyp.skipTypes(abstractInst).kind != tyRef and c.inSpawn == 0:
       message(c.graph.config, n.info, hintPerformance,
@@ -489,14 +495,14 @@ proc passCopyToSink(n: PNode; c: var Con; s: var Scope): PNode =
 
 proc isDangerousSeq(t: PType): bool {.inline.} =
   let t = t.skipTypes(abstractInst)
-  result = t.kind == tySequence and tfHasOwned notin t[0].flags
+  result = t.kind == tySequence and tfHasOwned notin t.elementType.flags
 
 proc containsConstSeq(n: PNode): bool =
   if n.kind == nkBracket and n.len > 0 and n.typ != nil and isDangerousSeq(n.typ):
     return true
   result = false
   case n.kind
-  of nkExprEqExpr, nkExprColonExpr, nkHiddenStdConv, nkHiddenSubConv:
+  of nkExprEqExpr, nkExprColonExpr, nkHiddenStdConv, nkHiddenSubConv, nkCast:
     result = containsConstSeq(n[1])
   of nkObjConstr, nkClosure:
     for i in 1..<n.len:
@@ -648,7 +654,7 @@ template handleNestedTempl(n, processCall: untyped, willProduceStmt = false,
       for j in 0 ..< it.len-1:
         branch[j] = copyTree(it[j])
       var ofScope = nestedScope(s, it.lastSon)
-      branch[^1] = if it[^1].typ.isEmptyType or willProduceStmt:
+      branch[^1] = if n.typ.isEmptyType or it[^1].typ.isEmptyType or willProduceStmt:
                      processScope(c, ofScope, maybeVoid(it[^1], ofScope))
                    else:
                      processScopeExpr(c, ofScope, it[^1], processCall, tmpFlags)
@@ -696,7 +702,7 @@ template handleNestedTempl(n, processCall: untyped, willProduceStmt = false,
         #Condition needs to be destroyed outside of the condition/branch scope
         branch[0] = p(it[0], c, s, normal)
 
-      branch[^1] = if it[^1].typ.isEmptyType or willProduceStmt:
+      branch[^1] = if n.typ.isEmptyType or it[^1].typ.isEmptyType or willProduceStmt:
                      processScope(c, branchScope, maybeVoid(it[^1], branchScope))
                    else:
                      processScopeExpr(c, branchScope, it[^1], processCall, tmpFlags)
@@ -742,7 +748,9 @@ template handleNestedTempl(n, processCall: untyped, willProduceStmt = false,
     result[^1] = maybeVoid(n[^1], s)
     dec c.inUncheckedAssignSection, inUncheckedAssignSection
 
-  else: assert(false)
+  else:
+    result = nil
+    assert(false)
 
 proc pRaiseStmt(n: PNode, c: var Con; s: var Scope): PNode =
   if optOwnedRefs in c.graph.config.globalOptions and n[0].kind != nkEmpty:
@@ -754,7 +762,7 @@ proc pRaiseStmt(n: PNode, c: var Con; s: var Scope): PNode =
       let tmp = c.getTemp(s, n[0].typ, n.info)
       var m = c.genCopyNoCheck(tmp, n[0], attachedAsgn)
       m.add p(n[0], c, s, normal)
-      c.finishCopy(m, n[0], isFromSink = false)
+      c.finishCopy(m, n[0], {}, isFromSink = false)
       result = newTree(nkStmtList, c.genWasMoved(tmp), m)
       var toDisarm = n[0]
       if toDisarm.kind == nkStmtListExpr: toDisarm = toDisarm.lastSon
@@ -777,8 +785,8 @@ template isCustomDestructor(c: Con, t: PType): bool =
 proc hasCustomDestructor(c: Con, t: PType): bool =
   result = isCustomDestructor(c, t)
   var obj = t
-  while obj.len > 0 and obj[0] != nil:
-    obj = skipTypes(obj[0], abstractPtrs)
+  while obj.baseClass != nil:
+    obj = skipTypes(obj.baseClass, abstractPtrs)
     result = result or isCustomDestructor(c, obj)
 
 proc p(n: PNode; c: var Con; s: var Scope; mode: ProcessMode; tmpFlags = {sfSingleUsedTemp}; inReturn = false): PNode =
@@ -814,14 +822,17 @@ proc p(n: PNode; c: var Con; s: var Scope; mode: ProcessMode; tmpFlags = {sfSing
           n[1].typ.skipTypes(abstractInst-{tyOwned}).kind == tyOwned:
         # allow conversions from owned to unowned via this little hack:
         let nTyp = n[1].typ
-        n[1].typ = n.typ
+        n[1].typ() = n.typ
         result[1] = p(n[1], c, s, sinkArg)
-        result[1].typ = nTyp
+        result[1].typ() = nTyp
       else:
         result[1] = p(n[1], c, s, sinkArg)
     elif n.kind in {nkObjDownConv, nkObjUpConv}:
       result = copyTree(n)
       result[0] = p(n[0], c, s, sinkArg)
+    elif n.kind == nkCast and n.typ.skipTypes(abstractInst).kind in {tyString, tySequence}:
+      result = copyTree(n)
+      result[1] = p(n[1], c, s, sinkArg)
     elif n.typ == nil:
       # 'raise X' can be part of a 'case' expression. Deal with it here:
       result = p(n, c, s, normal)
@@ -865,7 +876,8 @@ proc p(n: PNode; c: var Con; s: var Scope; mode: ProcessMode; tmpFlags = {sfSing
       for i in 1..<n.len:
         if n[i].kind == nkExprColonExpr:
           let field = lookupFieldAgain(t, n[i][0].sym)
-          if field != nil and sfCursor in field.flags:
+          if field != nil and (sfCursor in field.flags or field.typ.kind in {tyOpenArray, tyVarargs}):
+            # don't sink fields with openarray types
             result[i][1] = p(n[i][1], c, s, normal)
           else:
             result[i][1] = p(n[i][1], c, s, m)
@@ -886,8 +898,9 @@ proc p(n: PNode; c: var Con; s: var Scope; mode: ProcessMode; tmpFlags = {sfSing
       elif c.inSpawn > 0:
         c.inSpawn.dec
 
-      let parameters = n[0].typ
-      let L = if parameters != nil: parameters.len else: 0
+      # bug #23907; skips tyGenericInst for generic callbacks
+      let parameters = if n[0].typ != nil: n[0].typ.skipTypes(abstractInst) else: n[0].typ
+      let L = if parameters != nil: parameters.signatureLen else: 0
 
       when false:
         var isDangerous = false
@@ -1009,9 +1022,9 @@ proc p(n: PNode; c: var Con; s: var Scope; mode: ProcessMode; tmpFlags = {sfSing
           n[1].typ.skipTypes(abstractInst-{tyOwned}).kind == tyOwned:
         # allow conversions from owned to unowned via this little hack:
         let nTyp = n[1].typ
-        n[1].typ = n.typ
+        n[1].typ() = n.typ
         result[1] = p(n[1], c, s, mode)
-        result[1].typ = nTyp
+        result[1].typ() = nTyp
       else:
         result[1] = p(n[1], c, s, mode)
 
@@ -1068,6 +1081,7 @@ proc p(n: PNode; c: var Con; s: var Scope; mode: ProcessMode; tmpFlags = {sfSing
     of nkGotoState, nkState, nkAsmStmt:
       result = n
     else:
+      result = nil
       internalError(c.graph.config, n.info, "cannot inject destructors to node kind: " & $n.kind)
 
 proc sameLocation*(a, b: PNode): bool =
@@ -1160,7 +1174,7 @@ proc moveOrCopy(dest, ri: PNode; c: var Con; s: var Scope, flags: set[MoveOrCopy
         result = c.genCopy(dest, ri, flags)
         dec c.inEnsureMove, isEnsureMove
         result.add p(ri, c, s, consumed)
-        c.finishCopy(result, dest, isFromSink = false)
+        c.finishCopy(result, dest, flags, isFromSink = false)
     of nkBracket:
       # array constructor
       if ri.len > 0 and isDangerousSeq(ri.typ):
@@ -1168,7 +1182,7 @@ proc moveOrCopy(dest, ri: PNode; c: var Con; s: var Scope, flags: set[MoveOrCopy
         result = c.genCopy(dest, ri, flags)
         dec c.inEnsureMove, isEnsureMove
         result.add p(ri, c, s, consumed)
-        c.finishCopy(result, dest, isFromSink = false)
+        c.finishCopy(result, dest, flags, isFromSink = false)
       else:
         result = c.genSink(s, dest, p(ri, c, s, consumed), flags)
     of nkObjConstr, nkTupleConstr, nkClosure, nkCharLit..nkNilLit:
@@ -1178,8 +1192,9 @@ proc moveOrCopy(dest, ri: PNode; c: var Con; s: var Scope, flags: set[MoveOrCopy
         # Rule 3: `=sink`(x, z); wasMoved(z)
         let snk = c.genSink(s, dest, ri, flags)
         result = newTree(nkStmtList, snk, c.genWasMoved(ri))
-      elif ri.sym.kind != skParam and ri.sym.owner == c.owner and
-          isLastRead(ri, c, s) and canBeMoved(c, dest.typ) and not isCursor(ri):
+      elif ri.sym.kind != skParam and
+          isAnalysableFieldAccess(ri, c.owner) and
+          isLastRead(ri, c, s) and canBeMoved(c, dest.typ):
         # Rule 3: `=sink`(x, z); wasMoved(z)
         let snk = c.genSink(s, dest, ri, flags)
         result = newTree(nkStmtList, snk, c.genWasMoved(ri))
@@ -1188,7 +1203,7 @@ proc moveOrCopy(dest, ri: PNode; c: var Con; s: var Scope, flags: set[MoveOrCopy
         result = c.genCopy(dest, ri, flags)
         dec c.inEnsureMove, isEnsureMove
         result.add p(ri, c, s, consumed)
-        c.finishCopy(result, dest, isFromSink = false)
+        c.finishCopy(result, dest, flags, isFromSink = false)
     of nkHiddenSubConv, nkHiddenStdConv, nkConv, nkObjDownConv, nkObjUpConv, nkCast:
       result = c.genSink(s, dest, p(ri, c, s, sinkArg), flags)
     of nkStmtListExpr, nkBlockExpr, nkIfExpr, nkCaseStmt, nkTryStmt:
@@ -1208,7 +1223,7 @@ proc moveOrCopy(dest, ri: PNode; c: var Con; s: var Scope, flags: set[MoveOrCopy
         result = c.genCopy(dest, ri, flags)
         dec c.inEnsureMove, isEnsureMove
         result.add p(ri, c, s, consumed)
-        c.finishCopy(result, dest, isFromSink = false)
+        c.finishCopy(result, dest, flags, isFromSink = false)
 
 when false:
   proc computeUninit(c: var Con) =

compiler/installer.ini

@@ -6,7 +6,7 @@ Name: "Nim"
 Version: "$version"
 Platforms: """
   windows: i386;amd64
-  linux: i386;hppa;ia64;alpha;amd64;powerpc64;arm;sparc;sparc64;m68k;mips;mipsel;mips64;mips64el;powerpc;powerpc64el;arm64;riscv32;riscv64
+  linux: i386;hppa;ia64;alpha;amd64;powerpc64;arm;sparc;sparc64;m68k;mips;mipsel;mips64;mips64el;powerpc;powerpc64el;arm64;riscv32;riscv64;loongarch64
   macosx: i386;amd64;powerpc64;arm64
   solaris: i386;amd64;sparc;sparc64
   freebsd: i386;amd64;powerpc64;arm;arm64;riscv64;sparc64;mips;mipsel;mips64;mips64el;powerpc;powerpc64el
@@ -71,6 +71,7 @@ Files: "testament"
 Files: "nimsuggest"
 Files: "nimsuggest/tests/*.nim"
 Files: "changelogs/*.md"
+Files: "ci/funs.sh"
 
 [Lib]
 Files: "lib"
@@ -146,4 +147,4 @@ licenses: "bin/nim,MIT;lib/*,MIT;"
 
 [nimble]
 pkgName: "nim"
-pkgFiles: "compiler/*;doc/basicopt.txt;doc/advopt.txt;doc/nimdoc.css"
+pkgFiles: "compiler/*;doc/basicopt.txt;doc/advopt.txt;doc/nimdoc.css;doc/nimdoc.cls"

compiler/int128.nim

@@ -3,7 +3,7 @@
 ## hold all from `low(BiggestInt)` to `high(BiggestUInt)`, This
 ## type is for that purpose.
 
-from math import trunc
+from std/math import trunc
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
@@ -34,6 +34,7 @@ proc `$`*(a: Int128): string
 
 proc toInt128*[T: SomeInteger | bool](arg: T): Int128 =
   {.noSideEffect.}:
+    result = Zero
     when T is bool: result.sdata(0) = int32(arg)
     elif T is SomeUnsignedInt:
       when sizeof(arg) <= 4:
@@ -171,6 +172,7 @@ proc addToHex*(result: var string; arg: Int128) =
     i -= 1
 
 proc toHex*(arg: Int128): string =
+  result = ""
   result.addToHex(arg)
 
 proc inc*(a: var Int128, y: uint32 = 1) =
@@ -207,30 +209,35 @@ proc `==`*(a, b: Int128): bool =
   return true
 
 proc bitnot*(a: Int128): Int128 =
+  result = Zero
   result.udata[0] = not a.udata[0]
   result.udata[1] = not a.udata[1]
   result.udata[2] = not a.udata[2]
   result.udata[3] = not a.udata[3]
 
 proc bitand*(a, b: Int128): Int128 =
+  result = Zero
   result.udata[0] = a.udata[0] and b.udata[0]
   result.udata[1] = a.udata[1] and b.udata[1]
   result.udata[2] = a.udata[2] and b.udata[2]
   result.udata[3] = a.udata[3] and b.udata[3]
 
 proc bitor*(a, b: Int128): Int128 =
+  result = Zero
   result.udata[0] = a.udata[0] or b.udata[0]
   result.udata[1] = a.udata[1] or b.udata[1]
   result.udata[2] = a.udata[2] or b.udata[2]
   result.udata[3] = a.udata[3] or b.udata[3]
 
 proc bitxor*(a, b: Int128): Int128 =
+  result = Zero
   result.udata[0] = a.udata[0] xor b.udata[0]
   result.udata[1] = a.udata[1] xor b.udata[1]
   result.udata[2] = a.udata[2] xor b.udata[2]
   result.udata[3] = a.udata[3] xor b.udata[3]
 
 proc `shr`*(a: Int128, b: int): Int128 =
+  result = Zero
   let b = b and 127
   if b < 32:
     result.sdata(3) = a.sdata(3) shr b
@@ -257,6 +264,7 @@ proc `shr`*(a: Int128, b: int): Int128 =
     result.sdata(0) = a.sdata(3) shr (b and 31)
 
 proc `shl`*(a: Int128, b: int): Int128 =
+  result = Zero
   let b = b and 127
   if b < 32:
     result.udata[0] = a.udata[0] shl b
@@ -280,6 +288,7 @@ proc `shl`*(a: Int128, b: int): Int128 =
     result.udata[3] = a.udata[0] shl (b and 31)
 
 proc `+`*(a, b: Int128): Int128 =
+  result = Zero
   let tmp0 = uint64(a.udata[0]) + uint64(b.udata[0])
   result.udata[0] = cast[uint32](tmp0)
   let tmp1 = uint64(a.udata[1]) + uint64(b.udata[1]) + (tmp0 shr 32)
@@ -312,6 +321,7 @@ proc abs(a: int32): int =
   if a < 0: -a else: a
 
 proc `*`(a: Int128, b: uint32): Int128 =
+  result = Zero
   let tmp0 = uint64(a.udata[0]) * uint64(b)
   let tmp1 = uint64(a.udata[1]) * uint64(b)
   let tmp2 = uint64(a.udata[2]) * uint64(b)
@@ -330,10 +340,11 @@ proc `*`*(a: Int128, b: int32): Int128 =
   if b < 0:
     result = -result
 
-proc `*=`*(a: var Int128, b: int32): Int128 =
-  result = result * b
+proc `*=`(a: var Int128, b: int32) =
+  a = a * b
 
 proc makeInt128(high, low: uint64): Int128 =
+  result = Zero
   result.udata[0] = cast[uint32](low)
   result.udata[1] = cast[uint32](low shr 32)
   result.udata[2] = cast[uint32](high)
@@ -357,9 +368,10 @@ proc `*`*(lhs, rhs: Int128): Int128 =
 proc `*=`*(a: var Int128, b: Int128) =
   a = a * b
 
-import bitops
+import std/bitops
 
 proc fastLog2*(a: Int128): int =
+  result = 0
   if a.udata[3] != 0:
     return 96 + fastLog2(a.udata[3])
   if a.udata[2] != 0:
@@ -371,6 +383,8 @@ proc fastLog2*(a: Int128): int =
 
 proc divMod*(dividend, divisor: Int128): tuple[quotient, remainder: Int128] =
   assert(divisor != Zero)
+  result = (Zero, Zero)
+
   let isNegativeA = isNegative(dividend)
   let isNegativeB = isNegative(divisor)
 
@@ -537,24 +551,28 @@ proc toInt128*(arg: float64): Int128 =
     return res
 
 proc maskUInt64*(arg: Int128): Int128 {.noinit, inline.} =
+  result = Zero
   result.udata[0] = arg.udata[0]
   result.udata[1] = arg.udata[1]
   result.udata[2] = 0
   result.udata[3] = 0
 
 proc maskUInt32*(arg: Int128): Int128 {.noinit, inline.} =
+  result = Zero
   result.udata[0] = arg.udata[0]
   result.udata[1] = 0
   result.udata[2] = 0
   result.udata[3] = 0
 
 proc maskUInt16*(arg: Int128): Int128 {.noinit, inline.} =
+  result = Zero
   result.udata[0] = arg.udata[0] and 0xffff
   result.udata[1] = 0
   result.udata[2] = 0
   result.udata[3] = 0
 
 proc maskUInt8*(arg: Int128): Int128 {.noinit, inline.} =
+  result = Zero
   result.udata[0] = arg.udata[0] and 0xff
   result.udata[1] = 0
   result.udata[2] = 0
@@ -571,4 +589,4 @@ proc maskBytes*(arg: Int128, numbytes: int): Int128 {.noinit.} =
   of 8:
     return maskUInt64(arg)
   else:
-    assert(false, "masking only implemented for 1, 2, 4 and 8 bytes")
+    raiseAssert "masking only implemented for 1, 2, 4 and 8 bytes"

compiler/isolation_check.nim

@@ -11,7 +11,9 @@
 ## https://github.com/nim-lang/RFCs/issues/244 for more details.
 
 import
-  ast, types, renderer, intsets
+  ast, types, renderer
+
+import std/intsets
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
@@ -21,6 +23,7 @@ proc canAlias(arg, ret: PType; marker: var IntSet): bool
 proc canAliasN(arg: PType; n: PNode; marker: var IntSet): bool =
   case n.kind
   of nkRecList:
+    result = false
     for i in 0..<n.len:
       result = canAliasN(arg, n[i], marker)
       if result: return
@@ -36,7 +39,7 @@ proc canAliasN(arg: PType; n: PNode; marker: var IntSet): bool =
       else: discard
   of nkSym:
     result = canAlias(arg, n.sym.typ, marker)
-  else: discard
+  else: result = false
 
 proc canAlias(arg, ret: PType; marker: var IntSet): bool =
   if containsOrIncl(marker, ret.id):
@@ -51,17 +54,18 @@ proc canAlias(arg, ret: PType; marker: var IntSet): bool =
   of tyObject:
     if isFinal(ret):
       result = canAliasN(arg, ret.n, marker)
-      if not result and ret.len > 0 and ret[0] != nil:
-        result = canAlias(arg, ret[0], marker)
+      if not result and ret.baseClass != nil:
+        result = canAlias(arg, ret.baseClass, marker)
     else:
       result = true
   of tyTuple:
-    for i in 0..<ret.len:
-      result = canAlias(arg, ret[i], marker)
+    result = false
+    for r in ret.kids:
+      result = canAlias(arg, r, marker)
       if result: break
   of tyArray, tySequence, tyDistinct, tyGenericInst,
      tyAlias, tyInferred, tySink, tyLent, tyOwned, tyRef:
-    result = canAlias(arg, ret.lastSon, marker)
+    result = canAlias(arg, ret.skipModifier, marker)
   of tyProc:
     result = ret.callConv == ccClosure
   else:
@@ -115,14 +119,16 @@ proc containsDangerousRefAux(t: PType; marker: var IntSet): SearchResult =
   if result != NotFound: return result
   case t.kind
   of tyObject:
-    if t[0] != nil:
-      result = containsDangerousRefAux(t[0].skipTypes(skipPtrs), marker)
+    if t.baseClass != nil:
+      result = containsDangerousRefAux(t.baseClass.skipTypes(skipPtrs), marker)
     if result == NotFound: result = containsDangerousRefAux(t.n, marker)
   of tyGenericInst, tyDistinct, tyAlias, tySink:
-    result = containsDangerousRefAux(lastSon(t), marker)
-  of tyArray, tySet, tyTuple, tySequence:
-    for i in 0..<t.len:
-      result = containsDangerousRefAux(t[i], marker)
+    result = containsDangerousRefAux(skipModifier(t), marker)
+  of tyArray, tySet, tySequence:
+    result = containsDangerousRefAux(t.elementType, marker)
+  of tyTuple:
+    for a in t.kids:
+      result = containsDangerousRefAux(a, marker)
       if result == Found: return result
   else:
     discard
@@ -184,10 +190,12 @@ proc checkIsolate*(n: PNode): bool =
               return false
       result = true
     of nkIfStmt, nkIfExpr:
+      result = false
       for it in n:
         result = checkIsolate(it.lastSon)
         if not result: break
     of nkCaseStmt:
+      result = false
       for i in 1..<n.len:
         result = checkIsolate(n[i].lastSon)
         if not result: break
@@ -197,6 +205,7 @@ proc checkIsolate*(n: PNode): bool =
         result = checkIsolate(n[i].lastSon)
         if not result: break
     of nkBracket, nkTupleConstr, nkPar:
+      result = false
       for it in n:
         result = checkIsolate(it)
         if not result: break

compiler/jstypes.nim

@@ -69,7 +69,7 @@ proc genObjectFields(p: PProc, typ: PType, n: PNode): Rope =
   else: internalError(p.config, n.info, "genObjectFields")
 
 proc objHasTypeField(t: PType): bool {.inline.} =
-  tfInheritable in t.flags or t[0] != nil
+  tfInheritable in t.flags or t.baseClass != nil
 
 proc genObjectInfo(p: PProc, typ: PType, name: Rope) =
   let kind = if objHasTypeField(typ): tyObject else: tyTuple
@@ -79,9 +79,9 @@ proc genObjectInfo(p: PProc, typ: PType, name: Rope) =
   p.g.typeInfo.addf("var NNI$1 = $2;$n",
        [rope(typ.id), genObjectFields(p, typ, typ.n)])
   p.g.typeInfo.addf("$1.node = NNI$2;$n", [name, rope(typ.id)])
-  if (typ.kind == tyObject) and (typ[0] != nil):
+  if (typ.kind == tyObject) and (typ.baseClass != nil):
     p.g.typeInfo.addf("$1.base = $2;$n",
-         [name, genTypeInfo(p, typ[0].skipTypes(skipPtrs))])
+         [name, genTypeInfo(p, typ.baseClass.skipTypes(skipPtrs))])
 
 proc genTupleFields(p: PProc, typ: PType): Rope =
   var s: Rope = ""
@@ -117,9 +117,9 @@ proc genEnumInfo(p: PProc, typ: PType, name: Rope) =
   prepend(p.g.typeInfo, s)
   p.g.typeInfo.add(n)
   p.g.typeInfo.addf("$1.node = NNI$2;$n", [name, rope(typ.id)])
-  if typ[0] != nil:
+  if typ.baseClass != nil:
     p.g.typeInfo.addf("$1.base = $2;$n",
-         [name, genTypeInfo(p, typ[0])])
+         [name, genTypeInfo(p, typ.baseClass)])
 
 proc genTypeInfo(p: PProc, typ: PType): Rope =
   let t = typ.skipTypes({tyGenericInst, tyDistinct, tyAlias, tySink, tyOwned})
@@ -127,7 +127,7 @@ proc genTypeInfo(p: PProc, typ: PType): Rope =
   if containsOrIncl(p.g.typeInfoGenerated, t.id): return
   case t.kind
   of tyDistinct:
-    result = genTypeInfo(p, t[0])
+    result = genTypeInfo(p, t.skipModifier)
   of tyPointer, tyProc, tyBool, tyChar, tyCstring, tyString, tyInt..tyUInt64:
     var s =
       "var $1 = {size: 0,kind: $2,base: null,node: null,finalizer: null};$n" %
@@ -139,18 +139,18 @@ proc genTypeInfo(p: PProc, typ: PType): Rope =
               [result, rope(ord(t.kind))]
     prepend(p.g.typeInfo, s)
     p.g.typeInfo.addf("$1.base = $2;$n",
-         [result, genTypeInfo(p, t.lastSon)])
+         [result, genTypeInfo(p, t.elementType)])
   of tyArray:
     var s =
       "var $1 = {size: 0, kind: $2, base: null, node: null, finalizer: null};$n" %
               [result, rope(ord(t.kind))]
     prepend(p.g.typeInfo, s)
     p.g.typeInfo.addf("$1.base = $2;$n",
-         [result, genTypeInfo(p, t[1])])
+         [result, genTypeInfo(p, t.elementType)])
   of tyEnum: genEnumInfo(p, t, result)
   of tyObject: genObjectInfo(p, t, result)
   of tyTuple: genTupleInfo(p, t, result)
   of tyStatic:
-    if t.n != nil: result = genTypeInfo(p, lastSon t)
+    if t.n != nil: result = genTypeInfo(p, skipModifier t)
     else: internalError(p.config, "genTypeInfo(" & $t.kind & ')')
   else: internalError(p.config, "genTypeInfo(" & $t.kind & ')')

compiler/lambdalifting.nim

@@ -10,10 +10,12 @@
 # This file implements lambda lifting for the transformator.
 
 import
-  intsets, strutils, options, ast, astalgo, msgs,
-  idents, renderer, types, magicsys, lowerings, tables, modulegraphs, lineinfos,
+  options, ast, astalgo, msgs,
+  idents, renderer, types, magicsys, lowerings, modulegraphs, lineinfos,
   transf, liftdestructors, typeallowed
 
+import std/[strutils, tables, intsets]
+
 when defined(nimPreviewSlimSystem):
   import std/assertions
 
@@ -133,21 +135,23 @@ proc createClosureIterStateType*(g: ModuleGraph; iter: PSym; idgen: IdGenerator)
   var n = newNodeI(nkRange, iter.info)
   n.add newIntNode(nkIntLit, -1)
   n.add newIntNode(nkIntLit, 0)
-  result = newType(tyRange, nextTypeId(idgen), iter)
+  result = newType(tyRange, idgen, iter)
   result.n = n
   var intType = nilOrSysInt(g)
-  if intType.isNil: intType = newType(tyInt, nextTypeId(idgen), iter)
+  if intType.isNil: intType = newType(tyInt, idgen, iter)
   rawAddSon(result, intType)
 
 proc createStateField(g: ModuleGraph; iter: PSym; idgen: IdGenerator): PSym =
   result = newSym(skField, getIdent(g.cache, ":state"), idgen, iter, iter.info)
   result.typ = createClosureIterStateType(g, iter, idgen)
 
+template isIterator*(owner: PSym): bool =
+  owner.kind == skIterator and owner.typ.callConv == ccClosure
+
 proc createEnvObj(g: ModuleGraph; idgen: IdGenerator; owner: PSym; info: TLineInfo): PType =
-  # YYY meh, just add the state field for every closure for now, it's too
-  # hard to figure out if it comes from a closure iterator:
   result = createObj(g, idgen, owner, info, final=false)
-  rawAddField(result, createStateField(g, owner, idgen))
+  if owner.isIterator:
+    rawAddField(result, createStateField(g, owner, idgen))
 
 proc getClosureIterResult*(g: ModuleGraph; iter: PSym; idgen: IdGenerator): PSym =
   if resultPos < iter.ast.len:
@@ -155,7 +159,7 @@ proc getClosureIterResult*(g: ModuleGraph; iter: PSym; idgen: IdGenerator): PSym
   else:
     # XXX a bit hacky:
     result = newSym(skResult, getIdent(g.cache, ":result"), idgen, iter, iter.info, {})
-    result.typ = iter.typ[0]
+    result.typ = iter.typ.returnType
     incl(result.flags, sfUsed)
     iter.ast.add newSymNode(result)
 
@@ -170,24 +174,23 @@ proc addHiddenParam(routine: PSym, param: PSym) =
   assert sfFromGeneric in param.flags
   #echo "produced environment: ", param.id, " for ", routine.id
 
-proc getHiddenParam(g: ModuleGraph; routine: PSym): PSym =
+proc getEnvParam*(routine: PSym): PSym =
+  if routine.ast.isNil: return nil
   let params = routine.ast[paramsPos]
   let hidden = lastSon(params)
   if hidden.kind == nkSym and hidden.sym.kind == skParam and hidden.sym.name.s == paramName:
     result = hidden.sym
     assert sfFromGeneric in result.flags
   else:
+    result = nil
+
+proc getHiddenParam(g: ModuleGraph; routine: PSym): PSym =
+  result = getEnvParam(routine)
+  if result.isNil:
     # writeStackTrace()
     localError(g.config, routine.info, "internal error: could not find env param for " & routine.name.s)
     result = routine
 
-proc getEnvParam*(routine: PSym): PSym =
-  let params = routine.ast[paramsPos]
-  let hidden = lastSon(params)
-  if hidden.kind == nkSym and hidden.sym.name.s == paramName:
-    result = hidden.sym
-    assert sfFromGeneric in result.flags
-
 proc interestingVar(s: PSym): bool {.inline.} =
   result = s.kind in {skVar, skLet, skTemp, skForVar, skParam, skResult} and
     sfGlobal notin s.flags and
@@ -199,6 +202,8 @@ proc illegalCapture(s: PSym): bool {.inline.} =
 proc isInnerProc(s: PSym): bool =
   if s.kind in {skProc, skFunc, skMethod, skConverter, skIterator} and s.magic == mNone:
     result = s.skipGenericOwner.kind in routineKinds
+  else:
+    result = false
 
 proc newAsgnStmt(le, ri: PNode, info: TLineInfo): PNode =
   # Bugfix: unfortunately we cannot use 'nkFastAsgn' here as that would
@@ -224,23 +229,14 @@ proc makeClosure*(g: ModuleGraph; idgen: IdGenerator; prc: PSym; env: PNode; inf
   if tfHasAsgn in result.typ.flags or optSeqDestructors in g.config.globalOptions:
     prc.flags.incl sfInjectDestructors
 
-proc interestingIterVar(s: PSym): bool {.inline.} =
-  # XXX optimization: Only lift the variable if it lives across
-  # yield/return boundaries! This can potentially speed up
-  # closure iterators quite a bit.
-  result = s.kind in {skResult, skVar, skLet, skTemp, skForVar} and sfGlobal notin s.flags
-
-template isIterator*(owner: PSym): bool =
-  owner.kind == skIterator and owner.typ.callConv == ccClosure
-
-proc liftingHarmful(conf: ConfigRef; owner: PSym): bool {.inline.} =
+template liftingHarmful(conf: ConfigRef; owner: PSym): bool =
   ## lambda lifting can be harmful for JS-like code generators.
   let isCompileTime = sfCompileTime in owner.flags or owner.kind == skMacro
-  result = conf.backend == backendJs and not isCompileTime
+  jsNoLambdaLifting in conf.legacyFeatures and conf.backend == backendJs and not isCompileTime
 
 proc createTypeBoundOpsLL(g: ModuleGraph; refType: PType; info: TLineInfo; idgen: IdGenerator; owner: PSym) =
   if owner.kind != skMacro:
-    createTypeBoundOps(g, nil, refType.lastSon, info, idgen)
+    createTypeBoundOps(g, nil, refType.elementType, info, idgen)
     createTypeBoundOps(g, nil, refType, info, idgen)
     if tfHasAsgn in refType.flags or optSeqDestructors in g.config.globalOptions:
       owner.flags.incl sfInjectDestructors
@@ -279,15 +275,6 @@ proc liftIterSym*(g: ModuleGraph; n: PNode; idgen: IdGenerator; owner: PSym): PN
   createTypeBoundOpsLL(g, env.typ, n.info, idgen, owner)
   result.add makeClosure(g, idgen, iter, env, n.info)
 
-proc freshVarForClosureIter*(g: ModuleGraph; s: PSym; idgen: IdGenerator; owner: PSym): PNode =
-  let envParam = getHiddenParam(g, owner)
-  let obj = envParam.typ.skipTypes({tyOwned, tyRef, tyPtr})
-  let field = addField(obj, s, g.cache, idgen)
-
-  var access = newSymNode(envParam)
-  assert obj.kind == tyObject
-  result = rawIndirectAccess(access, field, s.info)
-
 # ------------------ new stuff -------------------------------------------
 
 proc markAsClosure(g: ModuleGraph; owner: PSym; n: PNode) =
@@ -297,8 +284,8 @@ proc markAsClosure(g: ModuleGraph; owner: PSym; n: PNode) =
     localError(g.config, n.info,
       ("'$1' is of type <$2> which cannot be captured as it would violate memory" &
        " safety, declared here: $3; using '-d:nimNoLentIterators' helps in some cases." &
-       " Consider using a <ref $2> which can be captured.") %
-      [s.name.s, typeToString(s.typ), g.config$s.info])
+       " Consider using a <ref T> which can be captured.") %
+      [s.name.s, typeToString(s.typ.skipTypes({tyVar})), g.config$s.info])
   elif not (owner.typ.isClosure or owner.isNimcall and not owner.isExplicitCallConv or isEnv):
     localError(g.config, n.info, "illegal capture '$1' because '$2' has the calling convention: <$3>" %
       [s.name.s, owner.name.s, $owner.typ.callConv])
@@ -316,12 +303,10 @@ type
     idgen: IdGenerator
 
 proc initDetectionPass(g: ModuleGraph; fn: PSym; idgen: IdGenerator): DetectionPass =
-  result.processed = initIntSet()
-  result.capturedVars = initIntSet()
-  result.ownerToType = initTable[int, PType]()
-  result.processed.incl(fn.id)
-  result.graph = g
-  result.idgen = idgen
+  result = DetectionPass(processed: toIntSet([fn.id]),
+    capturedVars: initIntSet(), ownerToType: initTable[int, PType](),
+    graph: g, idgen: idgen
+  )
 
 discard """
 proc outer =
@@ -337,15 +322,19 @@ proc getEnvTypeForOwner(c: var DetectionPass; owner: PSym;
                         info: TLineInfo): PType =
   result = c.ownerToType.getOrDefault(owner.id)
   if result.isNil:
-    result = newType(tyRef, nextTypeId(c.idgen), owner)
-    let obj = createEnvObj(c.graph, c.idgen, owner, info)
-    rawAddSon(result, obj)
+    let env = getEnvParam(owner)
+    if env.isNil or not owner.isIterator:
+      result = newType(tyRef, c.idgen, owner)
+      let obj = createEnvObj(c.graph, c.idgen, owner, info)
+      rawAddSon(result, obj)
+    else:
+      result = env.typ
     c.ownerToType[owner.id] = result
 
 proc asOwnedRef(c: var DetectionPass; t: PType): PType =
   if optOwnedRefs in c.graph.config.globalOptions:
     assert t.kind == tyRef
-    result = newType(tyOwned, nextTypeId(c.idgen), t.owner)
+    result = newType(tyOwned, c.idgen, t.owner)
     result.flags.incl tfHasOwned
     result.rawAddSon t
   else:
@@ -354,7 +343,7 @@ proc asOwnedRef(c: var DetectionPass; t: PType): PType =
 proc getEnvTypeForOwnerUp(c: var DetectionPass; owner: PSym;
                           info: TLineInfo): PType =
   var r = c.getEnvTypeForOwner(owner, info)
-  result = newType(tyPtr, nextTypeId(c.idgen), owner)
+  result = newType(tyPtr, c.idgen, owner)
   rawAddSon(result, r.skipTypes({tyOwned, tyRef, tyPtr}))
 
 proc createUpField(c: var DetectionPass; dest, dep: PSym; info: TLineInfo) =
@@ -431,6 +420,12 @@ proc addClosureParam(c: var DetectionPass; fn: PSym; info: TLineInfo) =
     localError(c.graph.config, fn.info, "internal error: inconsistent environment type")
   #echo "adding closure to ", fn.name.s
 
+proc iterEnvHasUpField(g: ModuleGraph, iter: PSym): bool =
+  let cp = getEnvParam(iter)
+  doAssert(cp != nil, "Env param not present in iter")
+  let upField = lookupInRecord(cp.typ.skipTypes({tyOwned, tyRef, tyPtr}).n, getIdent(g.cache, upName))
+  upField != nil
+
 proc detectCapturedVars(n: PNode; owner: PSym; c: var DetectionPass) =
   case n.kind
   of nkSym:
@@ -446,25 +441,15 @@ proc detectCapturedVars(n: PNode; owner: PSym; c: var DetectionPass) =
     if innerProc:
       if s.isIterator: c.somethingToDo = true
       if not c.processed.containsOrIncl(s.id):
-        let body = transformBody(c.graph, c.idgen, s, useCache)
+        let body = transformBody(c.graph, c.idgen, s, {useCache})
         detectCapturedVars(body, s, c)
     let ow = s.skipGenericOwner
-    let innerClosure = innerProc and s.typ.callConv == ccClosure and not s.isIterator
+    let innerClosure = innerProc and s.typ.callConv == ccClosure and (not s.isIterator or iterEnvHasUpField(c.graph, s))
     let interested = interestingVar(s)
     if ow == owner:
       if owner.isIterator:
         c.somethingToDo = true
         addClosureParam(c, owner, n.info)
-        if interestingIterVar(s):
-          if not c.capturedVars.contains(s.id):
-            if not c.inTypeOf: c.capturedVars.incl(s.id)
-            let obj = getHiddenParam(c.graph, owner).typ.skipTypes({tyOwned, tyRef, tyPtr})
-            #let obj = c.getEnvTypeForOwner(s.owner).skipTypes({tyOwned, tyRef, tyPtr})
-
-            if s.name.id == getIdent(c.graph.cache, ":state").id:
-              obj.n[0].sym.itemId = ItemId(module: s.itemId.module, item: -s.itemId.item)
-            else:
-              discard addField(obj, s, c.graph.cache, c.idgen)
     # direct or indirect dependency:
     elif innerClosure or interested:
       discard """
@@ -537,9 +522,8 @@ type
     unownedEnvVars: Table[int, PNode] # only required for --newruntime
 
 proc initLiftingPass(fn: PSym): LiftingPass =
-  result.processed = initIntSet()
-  result.processed.incl(fn.id)
-  result.envVars = initTable[int, PNode]()
+  result = LiftingPass(processed: toIntSet([fn.id]),
+                envVars: initTable[int, PNode]())
 
 proc accessViaEnvParam(g: ModuleGraph; n: PNode; owner: PSym): PNode =
   let s = n.sym
@@ -547,8 +531,8 @@ proc accessViaEnvParam(g: ModuleGraph; n: PNode; owner: PSym): PNode =
   let envParam = getHiddenParam(g, owner)
   if not envParam.isNil:
     var access = newSymNode(envParam)
+    var obj = access.typ.elementType
     while true:
-      let obj = access.typ[0]
       assert obj.kind == tyObject
       let field = getFieldFromObj(obj, s)
       if field != nil:
@@ -556,6 +540,7 @@ proc accessViaEnvParam(g: ModuleGraph; n: PNode; owner: PSym): PNode =
       let upField = lookupInRecord(obj.n, getIdent(g.cache, upName))
       if upField == nil: break
       access = rawIndirectAccess(access, upField, n.info)
+      obj = access.typ.baseClass
   localError(g.config, n.info, "internal error: environment misses: " & s.name.s)
   result = n
 
@@ -567,7 +552,7 @@ proc newEnvVar(cache: IdentCache; owner: PSym; typ: PType; info: TLineInfo; idge
   when false:
     if owner.kind == skIterator and owner.typ.callConv == ccClosure:
       let it = getHiddenParam(owner)
-      addUniqueField(it.typ[0], v)
+      addUniqueField(it.typ.elementType, v)
       result = indirectAccess(newSymNode(it), v, v.info)
     else:
       result = newSymNode(v)
@@ -624,7 +609,7 @@ proc rawClosureCreation(owner: PSym;
       let unowned = c.unownedEnvVars[owner.id]
       assert unowned != nil
       let env2 = copyTree(env)
-      env2.typ = unowned.typ
+      env2.typ() = unowned.typ
       result.add newAsgnStmt(unowned, env2, env.info)
       createTypeBoundOpsLL(d.graph, unowned.typ, env.info, d.idgen, owner)
 
@@ -664,16 +649,27 @@ proc finishClosureCreation(owner: PSym; d: var DetectionPass; c: LiftingPass;
     res.add newAsgnStmt(unowned, nilLit, info)
     createTypeBoundOpsLL(d.graph, unowned.typ, info, d.idgen, owner)
 
-proc closureCreationForIter(iter: PNode;
+proc getUpForIter(g: ModuleGraph; owner, iterOwner: PSym, expectedUpTyp: PType): PNode =
+  var p = getHiddenParam(g, owner)
+  var res = p.newSymNode
+  while res.typ.skipTypes({tyOwned, tyRef, tyPtr}) != expectedUpTyp:
+    let upField = lookupInRecord(p.typ.skipTypes({tyOwned, tyRef, tyPtr}).n, getIdent(g.cache, upName))
+    if upField == nil:
+      return nil
+    p = upField
+    res = rawIndirectAccess(res, upField, p.info)
+  res
+
+proc closureCreationForIter(owner: PSym, iter: PNode;
                             d: var DetectionPass; c: var LiftingPass): PNode =
   result = newNodeIT(nkStmtListExpr, iter.info, iter.sym.typ)
-  let owner = iter.sym.skipGenericOwner
-  var v = newSym(skVar, getIdent(d.graph.cache, envName), d.idgen, owner, iter.info)
+  let iterOwner = iter.sym.skipGenericOwner
+  var v = newSym(skVar, getIdent(d.graph.cache, envName), d.idgen, iterOwner, iter.info)
   incl(v.flags, sfShadowed)
   v.typ = asOwnedRef(d, getHiddenParam(d.graph, iter.sym).typ)
   var vnode: PNode
-  if owner.isIterator:
-    let it = getHiddenParam(d.graph, owner)
+  if iterOwner.isIterator:
+    let it = getHiddenParam(d.graph, iterOwner)
     addUniqueField(it.typ.skipTypes({tyOwned, tyRef, tyPtr}), v, d.graph.cache, d.idgen)
     vnode = indirectAccess(newSymNode(it), v, v.info)
   else:
@@ -682,12 +678,14 @@ proc closureCreationForIter(iter: PNode;
     addVar(vs, vnode)
     result.add(vs)
   result.add genCreateEnv(vnode)
-  createTypeBoundOpsLL(d.graph, vnode.typ, iter.info, d.idgen, owner)
+  createTypeBoundOpsLL(d.graph, vnode.typ, iter.info, d.idgen, iterOwner)
 
   let upField = lookupInRecord(v.typ.skipTypes({tyOwned, tyRef, tyPtr}).n, getIdent(d.graph.cache, upName))
   if upField != nil:
-    let u = setupEnvVar(owner, d, c, iter.info)
-    if u.typ.skipTypes({tyOwned, tyRef, tyPtr}) == upField.typ.skipTypes({tyOwned, tyRef, tyPtr}):
+    let expectedUpTyp = upField.typ.skipTypes({tyOwned, tyRef, tyPtr})
+    let u = if iterOwner == owner: setupEnvVar(iterOwner, d, c, iter.info)
+            else: getUpForIter(d.graph, owner, iterOwner, expectedUpTyp)
+    if u != nil and u.typ.skipTypes({tyOwned, tyRef, tyPtr}) == expectedUpTyp:
       result.add(newAsgnStmt(rawIndirectAccess(vnode, upField, iter.info),
                  u, iter.info))
     else:
@@ -721,11 +719,12 @@ proc symToClosure(n: PNode; owner: PSym; d: var DetectionPass;
     let available = getHiddenParam(d.graph, owner)
     result = makeClosure(d.graph, d.idgen, s, available.newSymNode, n.info)
   elif s.isIterator:
-    result = closureCreationForIter(n, d, c)
+    result = closureCreationForIter(owner, n, d, c)
   elif s.skipGenericOwner == owner:
     # direct dependency, so use the outer's env variable:
     result = makeClosure(d.graph, d.idgen, s, setupEnvVar(owner, d, c, n.info), n.info)
   else:
+    result = nil
     let available = getHiddenParam(d.graph, owner)
     let wanted = getHiddenParam(d.graph, s).typ
     # ugh: call through some other inner proc;
@@ -752,7 +751,7 @@ proc liftCapturedVars(n: PNode; owner: PSym; d: var DetectionPass;
         #  echo renderTree(s.getBody, {renderIds})
         let oldInContainer = c.inContainer
         c.inContainer = 0
-        var body = transformBody(d.graph, d.idgen, s, dontUseCache)
+        var body = transformBody(d.graph, d.idgen, s, {})
         body = liftCapturedVars(body, s, d, c)
         if c.envVars.getOrDefault(s.id).isNil:
           s.transformedBody = body
@@ -767,8 +766,6 @@ proc liftCapturedVars(n: PNode; owner: PSym; d: var DetectionPass;
     elif s.id in d.capturedVars:
       if s.owner != owner:
         result = accessViaEnvParam(d.graph, n, owner)
-      elif owner.isIterator and interestingIterVar(s):
-        result = accessViaEnvParam(d.graph, n, owner)
       else:
         result = accessViaEnvVar(n, owner, d, c)
   of nkEmpty..pred(nkSym), succ(nkSym)..nkNilLit, nkComesFrom,
@@ -789,7 +786,7 @@ proc liftCapturedVars(n: PNode; owner: PSym; d: var DetectionPass;
       let oldInContainer = c.inContainer
       c.inContainer = 0
       let m = newSymNode(n[namePos].sym)
-      m.typ = n.typ
+      m.typ() = n.typ
       result = liftCapturedVars(m, owner, d, c)
       c.inContainer = oldInContainer
   of nkHiddenStdConv:
@@ -876,20 +873,19 @@ proc liftIterToProc*(g: ModuleGraph; fn: PSym; body: PNode; ptrType: PType;
   fn.typ.callConv = oldCC
 
 proc liftLambdas*(g: ModuleGraph; fn: PSym, body: PNode; tooEarly: var bool;
-                  idgen: IdGenerator, force: bool): PNode =
-  # XXX backend == backendJs does not suffice! The compiletime stuff needs
-  # the transformation even when compiling to JS ...
-
-  # However we can do lifting for the stuff which is *only* compiletime.
+                  idgen: IdGenerator; flags: TransformFlags): PNode =
   let isCompileTime = sfCompileTime in fn.flags or fn.kind == skMacro
 
-  if body.kind == nkEmpty or (
+  if body.kind == nkEmpty or (jsNoLambdaLifting in g.config.legacyFeatures and
       g.config.backend == backendJs and not isCompileTime) or
-      (fn.skipGenericOwner.kind != skModule and not force):
+      (fn.skipGenericOwner.kind != skModule and force notin flags):
 
     # ignore forward declaration:
     result = body
     tooEarly = true
+    if fn.isIterator:
+      var d = initDetectionPass(g, fn, idgen)
+      addClosureParam(d, fn, body.info)
   else:
     var d = initDetectionPass(g, fn, idgen)
     detectCapturedVars(body, fn, d)
@@ -953,7 +949,7 @@ proc liftForLoop*(g: ModuleGraph; body: PNode; idgen: IdGenerator; owner: PSym):
   result = newNodeI(nkStmtList, body.info)
 
   # static binding?
-  var env: PSym
+  var env: PSym = nil
   let op = call[0]
   if op.kind == nkSym and op.sym.isIterator:
     # createClosure()

compiler/layeredtable.nim

@@ -0,0 +1,82 @@
+import std/tables
+import ast
+
+type
+  LayeredIdTableObj* {.acyclic.} = object
+    ## stack of type binding contexts implemented as a linked list
+    topLayer*: TypeMapping
+      ## the mappings on the current layer
+    nextLayer*: ref LayeredIdTableObj
+      ## the parent type binding context, possibly `nil`
+    previousLen*: int
+      ## total length of the bindings up to the parent layer,
+      ## used to track if new bindings were added
+
+const useRef = not defined(gcDestructors)
+  # implementation detail, only arc/orc doesn't cause issues when
+  # using LayeredIdTable as an object and not a ref
+
+when useRef:
+  type LayeredIdTable* = ref LayeredIdTableObj
+else:
+  type LayeredIdTable* = LayeredIdTableObj
+
+proc initLayeredTypeMap*(pt: sink TypeMapping = initTypeMapping()): LayeredIdTable =
+  result = LayeredIdTable(topLayer: pt, nextLayer: nil)
+
+proc shallowCopy*(pt: LayeredIdTable): LayeredIdTable {.inline.} =
+  ## copies only the type bindings of the current layer, but not any parent layers,
+  ## useful for write-only bindings
+  result = LayeredIdTable(topLayer: pt.topLayer, nextLayer: pt.nextLayer, previousLen: pt.previousLen)
+
+proc currentLen*(pt: LayeredIdTable): int =
+  ## the sum of the cached total binding count of the parents and
+  ## the current binding count, just used to track if bindings were added
+  pt.previousLen + pt.topLayer.len
+
+proc newTypeMapLayer*(pt: LayeredIdTable): LayeredIdTable =
+  result = LayeredIdTable(topLayer: initTable[ItemId, PType](), previousLen: pt.currentLen)
+  when useRef:
+    result.nextLayer = pt
+  else:
+    new(result.nextLayer)
+    result.nextLayer[] = pt
+
+proc setToPreviousLayer*(pt: var LayeredIdTable) {.inline.} =
+  when useRef:
+    pt = pt.nextLayer
+  else:
+    when defined(gcDestructors):
+      pt = pt.nextLayer[]
+    else:
+      # workaround refc
+      let tmp = pt.nextLayer[]
+      pt = tmp
+
+proc lookup(typeMap: ref LayeredIdTableObj, key: ItemId): PType =
+  result = nil
+  var tm = typeMap
+  while tm != nil:
+    result = getOrDefault(tm.topLayer, key)
+    if result != nil: return
+    tm = tm.nextLayer
+
+template lookup*(typeMap: ref LayeredIdTableObj, key: PType): PType =
+  ## recursively looks up binding of `key` in all parent layers
+  lookup(typeMap, key.itemId)
+
+when not useRef:
+  proc lookup(typeMap: LayeredIdTableObj, key: ItemId): PType {.inline.} =
+    result = getOrDefault(typeMap.topLayer, key)
+    if result == nil and typeMap.nextLayer != nil:
+      result = lookup(typeMap.nextLayer, key)
+
+  template lookup*(typeMap: LayeredIdTableObj, key: PType): PType =
+    lookup(typeMap, key.itemId)
+
+proc put(typeMap: var LayeredIdTable, key: ItemId, value: PType) {.inline.} =
+  typeMap.topLayer[key] = value
+
+template put*(typeMap: var LayeredIdTable, key, value: PType) =
+  ## binds `key` to `value` only in current layer
+  put(typeMap, key.itemId, value)

compiler/layouter.nim

@@ -9,7 +9,7 @@
 
 ## Layouter for nimpretty.
 
-import idents, lexer, lineinfos, llstream, options, msgs, strutils, pathutils
+import idents, lexer, ast, lineinfos, llstream, options, msgs, strutils, pathutils
 
 const
   MinLineLen = 15
@@ -243,23 +243,28 @@ proc renderTokens*(em: var Emitter): string =
 
   return content
 
-proc writeOut*(em: Emitter, content: string)  =
+type
+  FinalCheck = proc (content: string; origAst: PNode): bool {.nimcall.}
+
+proc writeOut*(em: Emitter; content: string; origAst: PNode; check: FinalCheck) =
   ## Write to disk
   let outFile = em.config.absOutFile
   if fileExists(outFile) and readFile(outFile.string) == content:
     discard "do nothing, see #9499"
     return
-  var f = llStreamOpen(outFile, fmWrite)
-  if f == nil:
-    rawMessage(em.config, errGenerated, "cannot open file: " & outFile.string)
-    return
-  f.llStreamWrite content
-  llStreamClose(f)
 
-proc closeEmitter*(em: var Emitter) =
+  if check(content, origAst):
+    var f = llStreamOpen(outFile, fmWrite)
+    if f == nil:
+      rawMessage(em.config, errGenerated, "cannot open file: " & outFile.string)
+      return
+    f.llStreamWrite content
+    llStreamClose(f)
+
+proc closeEmitter*(em: var Emitter; origAst: PNode; check: FinalCheck) =
   ## Renders emitter tokens and write to a file
   let content = renderTokens(em)
-  em.writeOut(content)
+  em.writeOut(content, origAst, check)
 
 proc wr(em: var Emitter; x: string; lt: LayoutToken) =
   em.tokens.add x

compiler/lexer.nim

@@ -16,8 +16,10 @@
 # DOS or Macintosh text files, even when it is not the native format.
 
 import
-  hashes, options, msgs, strutils, platform, idents, nimlexbase, llstream,
-  wordrecg, lineinfos, pathutils, parseutils
+  options, msgs, platform, idents, nimlexbase, llstream,
+  wordrecg, lineinfos, pathutils
+
+import std/[hashes, parseutils, strutils]
 
 when defined(nimPreviewSlimSystem):
   import std/[assertions, formatfloat]
@@ -120,7 +122,6 @@ type
                               # this is needed because scanning comments
                               # needs so much look-ahead
     currLineIndent*: int
-    strongSpaces*, allowTabs*: bool
     errorHandler*: ErrorHandler
     cache*: IdentCache
     when defined(nimsuggest):
@@ -148,9 +149,11 @@ proc isNimIdentifier*(s: string): bool =
     var i = 1
     while i < sLen:
       if s[i] == '_': inc(i)
-      if i < sLen and s[i] notin SymChars: return
+      if i < sLen and s[i] notin SymChars: return false
       inc(i)
     result = true
+  else:
+    result = false
 
 proc `$`*(tok: Token): string =
   case tok.tokType
@@ -172,32 +175,6 @@ proc printTok*(conf: ConfigRef; tok: Token) =
   # xxx factor with toLocation
   msgWriteln(conf, $tok.line & ":" & $tok.col & "\t" & $tok.tokType & " " & $tok)
 
-proc initToken*(L: var Token) =
-  L.tokType = tkInvalid
-  L.iNumber = 0
-  L.indent = 0
-  L.spacing = {}
-  L.literal = ""
-  L.fNumber = 0.0
-  L.base = base10
-  L.ident = nil
-  when defined(nimpretty):
-    L.commentOffsetA = 0
-    L.commentOffsetB = 0
-
-proc fillToken(L: var Token) =
-  L.tokType = tkInvalid
-  L.iNumber = 0
-  L.indent = 0
-  L.spacing = {}
-  setLen(L.literal, 0)
-  L.fNumber = 0.0
-  L.base = base10
-  L.ident = nil
-  when defined(nimpretty):
-    L.commentOffsetA = 0
-    L.commentOffsetB = 0
-
 proc openLexer*(lex: var Lexer, fileIdx: FileIndex, inputstream: PLLStream;
                  cache: IdentCache; config: ConfigRef) =
   openBaseLexer(lex, inputstream)
@@ -323,8 +300,7 @@ proc getNumber(L: var Lexer, result: var Token) =
     # Used to get slightly human friendlier err messages.
     const literalishChars = {'A'..'Z', 'a'..'z', '0'..'9', '_', '.', '\''}
     var msgPos = L.bufpos
-    var t: Token
-    t.literal = ""
+    var t = Token(literal: "")
     L.bufpos = startpos # Use L.bufpos as pos because of matchChars
     matchChars(L, t, literalishChars)
     # We must verify +/- specifically so that we're not past the literal
@@ -537,8 +513,8 @@ proc getNumber(L: var Lexer, result: var Token) =
         of floatTypes:
           result.fNumber = parseFloat(result.literal)
         of tkUInt64Lit, tkUIntLit:
-          var iNumber: uint64
-          var len: int
+          var iNumber: uint64 = uint64(0)
+          var len: int = 0
           try:
             len = parseBiggestUInt(result.literal, iNumber)
           except ValueError:
@@ -547,8 +523,8 @@ proc getNumber(L: var Lexer, result: var Token) =
             raise newException(ValueError, "invalid integer: " & result.literal)
           result.iNumber = cast[int64](iNumber)
         else:
-          var iNumber: int64
-          var len: int
+          var iNumber: int64 = int64(0)
+          var len: int = 0
           try:
             len = parseBiggestInt(result.literal, iNumber)
           except ValueError:
@@ -794,7 +770,7 @@ proc getString(L: var Lexer, tok: var Token, mode: StringMode) =
     if mode != normal: tok.tokType = tkRStrLit
     else: tok.tokType = tkStrLit
     while true:
-      var c = L.buf[pos]
+      let c = L.buf[pos]
       if c == '\"':
         if mode != normal and L.buf[pos+1] == '\"':
           inc(pos, 2)
@@ -820,7 +796,7 @@ proc getCharacter(L: var Lexer; tok: var Token) =
   tokenBegin(tok, L.bufpos)
   let startPos = L.bufpos
   inc(L.bufpos)               # skip '
-  var c = L.buf[L.bufpos]
+  let c = L.buf[L.bufpos]
   case c
   of '\0'..pred(' '), '\'':
     lexMessage(L, errGenerated, "invalid character literal")
@@ -938,7 +914,7 @@ proc getOperator(L: var Lexer, tok: var Token) =
   tokenBegin(tok, pos)
   var h: Hash = 0
   while true:
-    var c = L.buf[pos]
+    let c = L.buf[pos]
     if c in OpChars:
       h = h !& ord(c)
       inc(pos)
@@ -1006,22 +982,6 @@ proc getPrecedence*(tok: Token): int =
   of tkOr, tkXor, tkPtr, tkRef: result = 3
   else: return -10
 
-proc newlineFollows*(L: Lexer): bool =
-  var pos = L.bufpos
-  while true:
-    case L.buf[pos]
-    of ' ', '\t':
-      inc(pos)
-    of CR, LF:
-      result = true
-      break
-    of '#':
-      inc(pos)
-      if L.buf[pos] == '#': inc(pos)
-      if L.buf[pos] != '[': return true
-    else:
-      break
-
 proc skipMultiLineComment(L: var Lexer; tok: var Token; start: int;
                           isDoc: bool) =
   var pos = start
@@ -1113,9 +1073,7 @@ proc scanComment(L: var Lexer, tok: var Token) =
         toStrip = 0
       else:  # found first non-whitespace character
         stripInit = true
-    var lastBackslash = -1
     while L.buf[pos] notin {CR, LF, nimlexbase.EndOfFile}:
-      if L.buf[pos] == '\\': lastBackslash = pos+1
       tok.literal.add(L.buf[pos])
       inc(pos)
     tokenEndIgnore(tok, pos)
@@ -1158,7 +1116,7 @@ proc skip(L: var Lexer, tok: var Token) =
       inc(pos)
       tok.spacing.incl(tsLeading)
     of '\t':
-      if not L.allowTabs: lexMessagePos(L, errGenerated, pos, "tabs are not allowed, use spaces instead")
+      lexMessagePos(L, errGenerated, pos, "tabs are not allowed, use spaces instead")
       inc(pos)
     of CR, LF:
       tokenEndPrevious(tok, pos)
@@ -1226,7 +1184,7 @@ proc rawGetTok*(L: var Lexer, tok: var Token) =
         L.previousToken.line = tok.line.uint16
         L.previousToken.col = tok.col.int16
 
-  fillToken(tok)
+  reset(tok)
   if L.indentAhead >= 0:
     tok.indent = L.indentAhead
     L.currLineIndent = L.indentAhead
@@ -1238,7 +1196,7 @@ proc rawGetTok*(L: var Lexer, tok: var Token) =
     if tok.tokType == tkComment:
       L.indentAhead = L.currLineIndent
       return
-  var c = L.buf[L.bufpos]
+  let c = L.buf[L.bufpos]
   tok.line = L.lineNumber
   tok.col = getColNumber(L, L.bufpos)
   if c in SymStartChars - {'r', 'R'} - UnicodeOperatorStartChars:
@@ -1394,9 +1352,9 @@ proc rawGetTok*(L: var Lexer, tok: var Token) =
 
 proc getIndentWidth*(fileIdx: FileIndex, inputstream: PLLStream;
                      cache: IdentCache; config: ConfigRef): int =
-  var lex: Lexer
-  var tok: Token
-  initToken(tok)
+  result = 0
+  var lex: Lexer = default(Lexer)
+  var tok: Token = default(Token)
   openLexer(lex, fileIdx, inputstream, cache, config)
   var prevToken = tkEof
   while tok.tokType != tkEof:
@@ -1409,11 +1367,11 @@ proc getIndentWidth*(fileIdx: FileIndex, inputstream: PLLStream;
 
 proc getPrecedence*(ident: PIdent): int =
   ## assumes ident is binary operator already
-  var tok: Token
-  initToken(tok)
-  tok.ident = ident
-  tok.tokType =
-    if tok.ident.id in ord(tokKeywordLow) - ord(tkSymbol)..ord(tokKeywordHigh) - ord(tkSymbol):
-      TokType(tok.ident.id + ord(tkSymbol))
-    else: tkOpr
+  let
+    tokType =
+      if ident.id in ord(tokKeywordLow) - ord(tkSymbol)..ord(tokKeywordHigh) - ord(tkSymbol):
+        TokType(ident.id + ord(tkSymbol))
+      else: tkOpr
+    tok = Token(ident: ident, tokType: tokType)
+
   getPrecedence(tok)

compiler/liftdestructors.nim

@@ -11,8 +11,9 @@
 ## (`=sink`, `=copy`, `=destroy`, `=deepCopy`, `=wasMoved`, `=dup`).
 
 import modulegraphs, lineinfos, idents, ast, renderer, semdata,
-  sighashes, lowerings, options, types, msgs, magicsys, tables, ccgutils
+  sighashes, lowerings, options, types, msgs, magicsys, ccgutils
 
+import std/tables
 from trees import isCaseObj
 
 when defined(nimPreviewSlimSystem):
@@ -48,17 +49,17 @@ proc at(a, i: PNode, elemType: PType): PNode =
   result = newNodeI(nkBracketExpr, a.info, 2)
   result[0] = a
   result[1] = i
-  result.typ = elemType
+  result.typ() = elemType
 
 proc destructorOverridden(g: ModuleGraph; t: PType): bool =
   let op = getAttachedOp(g, t, attachedDestructor)
   op != nil and sfOverridden in op.flags
 
 proc fillBodyTup(c: var TLiftCtx; t: PType; body, x, y: PNode) =
-  for i in 0..<t.len:
+  for i, a in t.ikids:
     let lit = lowerings.newIntLit(c.g, x.info, i)
-    let b = if c.kind == attachedTrace: y else: y.at(lit, t[i])
-    fillBody(c, t[i], body, x.at(lit, t[i]), b)
+    let b = if c.kind == attachedTrace: y else: y.at(lit, a)
+    fillBody(c, a, body, x.at(lit, a), b)
 
 proc dotField(x: PNode, f: PSym): PNode =
   result = newNodeI(nkDotExpr, x.info, 2)
@@ -67,7 +68,7 @@ proc dotField(x: PNode, f: PSym): PNode =
   else:
     result[0] = x
   result[1] = newSymNode(f, x.info)
-  result.typ = f.typ
+  result.typ() = f.typ
 
 proc newAsgnStmt(le, ri: PNode): PNode =
   result = newNodeI(nkAsgn, le.info, 2)
@@ -87,7 +88,7 @@ proc defaultOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
     body.add newAsgnStmt(x, y)
   elif c.kind == attachedDestructor and c.addMemReset:
     let call = genBuiltin(c, mDefault, "default", x)
-    call.typ = t
+    call.typ() = t
     body.add newAsgnStmt(x, call)
   elif c.kind == attachedWasMoved:
     body.add genBuiltin(c, mWasMoved, "`=wasMoved`", x)
@@ -104,7 +105,7 @@ proc genWhileLoop(c: var TLiftCtx; i, dest: PNode): PNode =
   result = newNodeI(nkWhileStmt, c.info, 2)
   let cmp = genBuiltin(c, mLtI, "<", i)
   cmp.add genLen(c.g, dest)
-  cmp.typ = getSysType(c.g, c.info, tyBool)
+  cmp.typ() = getSysType(c.g, c.info, tyBool)
   result[0] = cmp
   result[1] = newNodeI(nkStmtList, c.info)
 
@@ -126,10 +127,10 @@ proc genContainerOf(c: var TLiftCtx; objType: PType, field, x: PSym): PNode =
   dotExpr.add newSymNode(field)
 
   let offsetOf = genBuiltin(c, mOffsetOf, "offsetof", dotExpr)
-  offsetOf.typ = intType
+  offsetOf.typ() = intType
 
   let minusExpr = genBuiltin(c, mSubI, "-", castExpr1)
-  minusExpr.typ = intType
+  minusExpr.typ() = intType
   minusExpr.add offsetOf
 
   let objPtr = makePtrType(objType.owner, objType, c.idgen)
@@ -138,9 +139,9 @@ proc genContainerOf(c: var TLiftCtx; objType: PType, field, x: PSym): PNode =
   result.add minusExpr
 
 proc destructorCall(c: var TLiftCtx; op: PSym; x: PNode): PNode =
-  var destroy = newNodeIT(nkCall, x.info, op.typ[0])
+  var destroy = newNodeIT(nkCall, x.info, op.typ.returnType)
   destroy.add(newSymNode(op))
-  if op.typ[1].kind != tyVar:
+  if op.typ.firstParamType.kind != tyVar:
     destroy.add x
   else:
     destroy.add genAddr(c, x)
@@ -152,7 +153,7 @@ proc destructorCall(c: var TLiftCtx; op: PSym; x: PNode): PNode =
     result = destroy
 
 proc genWasMovedCall(c: var TLiftCtx; op: PSym; x: PNode): PNode =
-  result = newNodeIT(nkCall, x.info, op.typ[0])
+  result = newNodeIT(nkCall, x.info, op.typ.returnType)
   result.add(newSymNode(op))
   result.add genAddr(c, x)
 
@@ -222,18 +223,24 @@ proc fillBodyObj(c: var TLiftCtx; n, body, x, y: PNode; enforceDefaultOp: bool,
     illFormedAstLocal(n, c.g.config)
 
 proc fillBodyObjTImpl(c: var TLiftCtx; t: PType, body, x, y: PNode) =
-  if t.len > 0 and t[0] != nil:
-    let obj = newNodeIT(nkHiddenSubConv, c.info, t[0])
-    obj.add newNodeI(nkEmpty, c.info)
-    obj.add x
-    fillBody(c, skipTypes(t[0], abstractPtrs), body, obj, y)
+  if t.baseClass != nil:
+    let dest = newNodeIT(nkHiddenSubConv, c.info, t.baseClass)
+    dest.add newNodeI(nkEmpty, c.info)
+    dest.add x
+    var src = y
+    if c.kind in {attachedAsgn, attachedDeepCopy, attachedSink}:
+      src = newNodeIT(nkHiddenSubConv, c.info, t.baseClass)
+      src.add newNodeI(nkEmpty, c.info)
+      src.add y
+
+    fillBody(c, skipTypes(t.baseClass, abstractPtrs), body, dest, src)
   fillBodyObj(c, t.n, body, x, y, enforceDefaultOp = false)
 
 proc fillBodyObjT(c: var TLiftCtx; t: PType, body, x, y: PNode) =
   var hasCase = isCaseObj(t.n)
   var obj = t
-  while obj.len > 0 and obj[0] != nil:
-    obj = skipTypes(obj[0], abstractPtrs)
+  while obj.baseClass != nil:
+    obj = skipTypes(obj.baseClass, abstractPtrs)
     hasCase = hasCase or isCaseObj(obj.n)
 
   if hasCase and c.kind in {attachedAsgn, attachedDeepCopy}:
@@ -258,7 +265,7 @@ proc fillBodyObjT(c: var TLiftCtx; t: PType, body, x, y: PNode) =
       # because the wasMoved(dest) call would zero out src, if dest aliases src.
       var cond = newTree(nkCall, newSymNode(c.g.getSysMagic(c.info, "==", mEqRef)),
         newTreeIT(nkAddr, c.info, makePtrType(c.fn, x.typ, c.idgen), x), newTreeIT(nkAddr, c.info, makePtrType(c.fn, y.typ, c.idgen), y))
-      cond.typ = getSysType(c.g, x.info, tyBool)
+      cond.typ() = getSysType(c.g, x.info, tyBool)
       body.add genIf(c, cond, newTreeI(nkReturnStmt, c.info, newNodeI(nkEmpty, c.info)))
     var temp = newSym(skTemp, getIdent(c.g.cache, lowerings.genPrefix), c.idgen, c.fn, c.info)
     temp.typ = x.typ
@@ -289,11 +296,11 @@ proc fillBodyObjT(c: var TLiftCtx; t: PType, body, x, y: PNode) =
 
 proc boolLit*(g: ModuleGraph; info: TLineInfo; value: bool): PNode =
   result = newIntLit(g, info, ord value)
-  result.typ = getSysType(g, info, tyBool)
+  result.typ() = getSysType(g, info, tyBool)
 
 proc getCycleParam(c: TLiftCtx): PNode =
   assert c.kind in {attachedAsgn, attachedDup}
-  if c.fn.typ.len == 4:
+  if c.fn.typ.len == 3 + ord(c.kind == attachedAsgn):
     result = c.fn.typ.n.lastSon
     assert result.kind == nkSym
     assert result.sym.name.s == "cyclic"
@@ -307,27 +314,35 @@ proc newHookCall(c: var TLiftCtx; op: PSym; x, y: PNode): PNode =
   result.add newSymNode(op)
   if sfNeverRaises notin op.flags:
     c.canRaise = true
-  if op.typ.sons[1].kind == tyVar:
+  if op.typ.firstParamType.kind == tyVar:
     result.add genAddr(c, x)
   else:
     result.add x
   if y != nil:
     result.add y
-  if op.typ.len == 4:
+  if op.typ.signatureLen == 4:
     assert y != nil
-    if c.fn.typ.len == 4:
+    if c.fn.typ.signatureLen == 4:
       result.add getCycleParam(c)
     else:
       # assume the worst: A cycle is created:
       result.add boolLit(c.g, y.info, true)
 
 proc newOpCall(c: var TLiftCtx; op: PSym; x: PNode): PNode =
-  result = newNodeIT(nkCall, x.info, op.typ[0])
+  result = newNodeIT(nkCall, x.info, op.typ.returnType)
   result.add(newSymNode(op))
   result.add x
   if sfNeverRaises notin op.flags:
     c.canRaise = true
 
+  if c.kind == attachedDup and op.typ.len == 3:
+    assert x != nil
+    if c.fn.typ.len == 3:
+      result.add getCycleParam(c)
+    else:
+      # assume the worst: A cycle is created:
+      result.add boolLit(c.g, x.info, true)
+
 proc newDeepCopyCall(c: var TLiftCtx; op: PSym; x, y: PNode): PNode =
   result = newAsgnStmt(x, newOpCall(c, op, y))
 
@@ -372,6 +387,8 @@ proc considerAsgnOrSink(c: var TLiftCtx; t: PType; body, x, y: PNode;
       op = produceSym(c.g, c.c, t, c.kind, c.info, c.idgen)
       body.add newHookCall(c, op, x, y)
       result = true
+    else:
+      result = false
   elif tfHasAsgn in t.flags:
     var op: PSym
     if sameType(t, c.asgnForType):
@@ -401,6 +418,8 @@ proc considerAsgnOrSink(c: var TLiftCtx; t: PType; body, x, y: PNode;
     assert op.ast[genericParamsPos].kind == nkEmpty
     body.add newHookCall(c, op, x, y)
     result = true
+  else:
+    result = false
 
 proc addDestructorCall(c: var TLiftCtx; orig: PType; body, x: PNode) =
   let t = orig.skipTypes(abstractInst - {tyDistinct})
@@ -440,6 +459,8 @@ proc considerUserDefinedOp(c: var TLiftCtx; t: PType; body, x, y: PNode): bool =
       onUse(c.info, op)
       body.add destructorCall(c, op, x)
       result = true
+    else:
+      result = false
     #result = addDestructorCall(c, t, body, x)
   of attachedAsgn, attachedSink, attachedTrace:
     var op = getAttachedOp(c.g, t, c.kind)
@@ -460,6 +481,8 @@ proc considerUserDefinedOp(c: var TLiftCtx; t: PType; body, x, y: PNode): bool =
       onUse(c.info, op)
       body.add newDeepCopyCall(c, op, x, y)
       result = true
+    else:
+      result = false
 
   of attachedWasMoved:
     var op = getAttachedOp(c.g, t, attachedWasMoved)
@@ -474,6 +497,8 @@ proc considerUserDefinedOp(c: var TLiftCtx; t: PType; body, x, y: PNode): bool =
       onUse(c.info, op)
       body.add genWasMovedCall(c, op, x)
       result = true
+    else:
+      result = false
 
   of attachedDup:
     var op = getAttachedOp(c.g, t, attachedDup)
@@ -488,6 +513,8 @@ proc considerUserDefinedOp(c: var TLiftCtx; t: PType; body, x, y: PNode): bool =
       onUse(c.info, op)
       body.add newDupCall(c, op, x, y)
       result = true
+    else:
+      result = false
 
 proc declareCounter(c: var TLiftCtx; body: PNode; first: BiggestInt): PNode =
   var temp = newSym(skTemp, getIdent(c.g.cache, lowerings.genPrefix), c.idgen, c.fn, c.info)
@@ -518,18 +545,18 @@ proc newSeqCall(c: var TLiftCtx; x, y: PNode): PNode =
   # don't call genAddr(c, x) here:
   result = genBuiltin(c, mNewSeq, "newSeq", x)
   let lenCall = genBuiltin(c, mLengthSeq, "len", y)
-  lenCall.typ = getSysType(c.g, x.info, tyInt)
+  lenCall.typ() = getSysType(c.g, x.info, tyInt)
   result.add lenCall
 
 proc setLenStrCall(c: var TLiftCtx; x, y: PNode): PNode =
   let lenCall = genBuiltin(c, mLengthStr, "len", y)
-  lenCall.typ = getSysType(c.g, x.info, tyInt)
+  lenCall.typ() = getSysType(c.g, x.info, tyInt)
   result = genBuiltin(c, mSetLengthStr, "setLen", x) # genAddr(g, x))
   result.add lenCall
 
 proc setLenSeqCall(c: var TLiftCtx; t: PType; x, y: PNode): PNode =
   let lenCall = genBuiltin(c, mLengthSeq, "len", y)
-  lenCall.typ = getSysType(c.g, x.info, tyInt)
+  lenCall.typ() = getSysType(c.g, x.info, tyInt)
   var op = getSysMagic(c.g, x.info, "setLen", mSetLengthSeq)
   op = instantiateGeneric(c, op, t, t)
   result = newTree(nkCall, newSymNode(op, x.info), x, lenCall)
@@ -538,7 +565,7 @@ proc forallElements(c: var TLiftCtx; t: PType; body, x, y: PNode) =
   let counterIdx = body.len
   let i = declareCounter(c, body, toInt64(firstOrd(c.g.config, t)))
   let whileLoop = genWhileLoop(c, i, x)
-  let elemType = t.lastSon
+  let elemType = t.elementType
   let b = if c.kind == attachedTrace: y else: y.at(i, elemType)
   fillBody(c, elemType, whileLoop[1], x.at(i, elemType), b)
   if whileLoop[1].len > 0:
@@ -552,7 +579,7 @@ proc checkSelfAssignment(c: var TLiftCtx; t: PType; body, x, y: PNode) =
       newTreeIT(nkAddr, c.info, makePtrType(c.fn, x.typ, c.idgen), x),
       newTreeIT(nkAddr, c.info, makePtrType(c.fn, y.typ, c.idgen), y)
       )
-  cond.typ = getSysType(c.g, c.info, tyBool)
+  cond.typ() = getSysType(c.g, c.info, tyBool)
   body.add genIf(c, cond, newTreeI(nkReturnStmt, c.info, newNodeI(nkEmpty, c.info)))
 
 proc fillSeqOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
@@ -649,7 +676,7 @@ proc fillStrOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
 
 proc cyclicType*(g: ModuleGraph, t: PType): bool =
   case t.kind
-  of tyRef: result = types.canFormAcycle(g, t.lastSon)
+  of tyRef: result = types.canFormAcycle(g, t.elementType)
   of tyProc: result = t.callConv == ccClosure
   else: result = false
 
@@ -674,7 +701,7 @@ proc atomicRefOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
 
   ]#
   var actions = newNodeI(nkStmtList, c.info)
-  let elemType = t.lastSon
+  let elemType = t.elementType
 
   createTypeBoundOps(c.g, c.c, elemType, c.info, c.idgen)
   let isCyclic = c.g.config.selectedGC == gcOrc and types.canFormAcycle(c.g, elemType)
@@ -693,7 +720,7 @@ proc atomicRefOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
   if isFinal(elemType):
     addDestructorCall(c, elemType, actions, genDeref(tmp, nkDerefExpr))
     var alignOf = genBuiltin(c, mAlignOf, "alignof", newNodeIT(nkType, c.info, elemType))
-    alignOf.typ = getSysType(c.g, c.info, tyInt)
+    alignOf.typ() = getSysType(c.g, c.info, tyInt)
     actions.add callCodegenProc(c.g, "nimRawDispose", c.info, tmp, alignOf)
   else:
     addDestructorCall(c, elemType, newNodeI(nkStmtList, c.info), genDeref(tmp, nkDerefExpr))
@@ -703,7 +730,7 @@ proc atomicRefOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
   if isCyclic:
     if isFinal(elemType):
       let typInfo = genBuiltin(c, mGetTypeInfoV2, "getTypeInfoV2", newNodeIT(nkType, x.info, elemType))
-      typInfo.typ = getSysType(c.g, c.info, tyPointer)
+      typInfo.typ() = getSysType(c.g, c.info, tyPointer)
       cond = callCodegenProc(c.g, "nimDecRefIsLastCyclicStatic", c.info, tmp, typInfo)
     else:
       cond = callCodegenProc(c.g, "nimDecRefIsLastCyclicDyn", c.info, tmp)
@@ -711,7 +738,7 @@ proc atomicRefOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
     cond = callCodegenProc(c.g, "nimDecRefIsLastDyn", c.info, x)
   else:
     cond = callCodegenProc(c.g, "nimDecRefIsLast", c.info, x)
-  cond.typ = getSysType(c.g, x.info, tyBool)
+  cond.typ() = getSysType(c.g, x.info, tyBool)
 
   case c.kind
   of attachedSink:
@@ -738,7 +765,7 @@ proc atomicRefOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
     if isCyclic:
       if isFinal(elemType):
         let typInfo = genBuiltin(c, mGetTypeInfoV2, "getTypeInfoV2", newNodeIT(nkType, x.info, elemType))
-        typInfo.typ = getSysType(c.g, c.info, tyPointer)
+        typInfo.typ() = getSysType(c.g, c.info, tyPointer)
         body.add callCodegenProc(c.g, "nimTraceRef", c.info, genAddrOf(x, c.idgen), typInfo, y)
       else:
         # If the ref is polymorphic we have to account for this
@@ -759,7 +786,7 @@ proc atomicClosureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
   ## Closures are really like refs except they always use a virtual destructor
   ## and we need to do the refcounting only on the ref field which we call 'xenv':
   let xenv = genBuiltin(c, mAccessEnv, "accessEnv", x)
-  xenv.typ = getSysType(c.g, c.info, tyPointer)
+  xenv.typ() = getSysType(c.g, c.info, tyPointer)
 
   let isCyclic = c.g.config.selectedGC == gcOrc
   let tmp =
@@ -775,7 +802,7 @@ proc atomicClosureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
     if isCyclic: "nimDecRefIsLastCyclicDyn"
     else: "nimDecRefIsLast"
   let cond = callCodegenProc(c.g, decRefProc, c.info, tmp)
-  cond.typ = getSysType(c.g, x.info, tyBool)
+  cond.typ() = getSysType(c.g, x.info, tyBool)
 
   case c.kind
   of attachedSink:
@@ -787,7 +814,7 @@ proc atomicClosureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
       body.add newAsgnStmt(x, y)
   of attachedAsgn:
     let yenv = genBuiltin(c, mAccessEnv, "accessEnv", y)
-    yenv.typ = getSysType(c.g, c.info, tyPointer)
+    yenv.typ() = getSysType(c.g, c.info, tyPointer)
     if isCyclic:
       body.add genIf(c, yenv, callCodegenProc(c.g, "nimIncRefCyclic", c.info, yenv, getCycleParam(c)))
       body.add newAsgnStmt(x, y)
@@ -799,7 +826,7 @@ proc atomicClosureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
       body.add newAsgnStmt(x, y)
   of attachedDup:
     let yenv = genBuiltin(c, mAccessEnv, "accessEnv", y)
-    yenv.typ = getSysType(c.g, c.info, tyPointer)
+    yenv.typ() = getSysType(c.g, c.info, tyPointer)
     if isCyclic:
       body.add newAsgnStmt(x, y)
       body.add genIf(c, yenv, callCodegenProc(c.g, "nimIncRefCyclic", c.info, yenv, getCycleParam(c)))
@@ -844,14 +871,14 @@ proc weakrefOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
 proc ownedRefOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
   var actions = newNodeI(nkStmtList, c.info)
 
-  let elemType = t.lastSon
+  let elemType = t.skipModifier
   #fillBody(c, elemType, actions, genDeref(x), genDeref(y))
   #var disposeCall = genBuiltin(c, mDispose, "dispose", x)
 
   if isFinal(elemType):
     addDestructorCall(c, elemType, actions, genDeref(x, nkDerefExpr))
     var alignOf = genBuiltin(c, mAlignOf, "alignof", newNodeIT(nkType, c.info, elemType))
-    alignOf.typ = getSysType(c.g, c.info, tyInt)
+    alignOf.typ() = getSysType(c.g, c.info, tyInt)
     actions.add callCodegenProc(c.g, "nimRawDispose", c.info, x, alignOf)
   else:
     addDestructorCall(c, elemType, newNodeI(nkStmtList, c.info), genDeref(x, nkDerefExpr))
@@ -874,14 +901,14 @@ proc closureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
     # a big problem is that we don't know the environment's type here, so we
     # have to go through some indirection; we delegate this to the codegen:
     let call = newNodeI(nkCall, c.info, 2)
-    call.typ = t
+    call.typ() = t
     call[0] = newSymNode(createMagic(c.g, c.idgen, "deepCopy", mDeepCopy))
     call[1] = y
     body.add newAsgnStmt(x, call)
   elif (optOwnedRefs in c.g.config.globalOptions and
       optRefCheck in c.g.config.options) or c.g.config.selectedGC in {gcArc, gcAtomicArc, gcOrc}:
     let xx = genBuiltin(c, mAccessEnv, "accessEnv", x)
-    xx.typ = getSysType(c.g, c.info, tyPointer)
+    xx.typ() = getSysType(c.g, c.info, tyPointer)
     case c.kind
     of attachedSink:
       # we 'nil' y out afterwards so we *need* to take over its reference
@@ -890,13 +917,13 @@ proc closureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
       body.add newAsgnStmt(x, y)
     of attachedAsgn:
       let yy = genBuiltin(c, mAccessEnv, "accessEnv", y)
-      yy.typ = getSysType(c.g, c.info, tyPointer)
+      yy.typ() = getSysType(c.g, c.info, tyPointer)
       body.add genIf(c, yy, callCodegenProc(c.g, "nimIncRef", c.info, yy))
       body.add genIf(c, xx, callCodegenProc(c.g, "nimDecWeakRef", c.info, xx))
       body.add newAsgnStmt(x, y)
     of attachedDup:
       let yy = genBuiltin(c, mAccessEnv, "accessEnv", y)
-      yy.typ = getSysType(c.g, c.info, tyPointer)
+      yy.typ() = getSysType(c.g, c.info, tyPointer)
       body.add newAsgnStmt(x, y)
       body.add genIf(c, yy, callCodegenProc(c.g, "nimIncRef", c.info, yy))
     of attachedDestructor:
@@ -911,7 +938,7 @@ proc closureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
 
 proc ownedClosureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
   let xx = genBuiltin(c, mAccessEnv, "accessEnv", x)
-  xx.typ = getSysType(c.g, c.info, tyPointer)
+  xx.typ() = getSysType(c.g, c.info, tyPointer)
   var actions = newNodeI(nkStmtList, c.info)
   #discard addDestructorCall(c, elemType, newNodeI(nkStmtList, c.info), genDeref(xx))
   actions.add callCodegenProc(c.g, "nimDestroyAndDispose", c.info, xx)
@@ -1010,7 +1037,7 @@ proc fillBody(c: var TLiftCtx; t: PType; body, x, y: PNode) =
           fillBodyObjT(c, t, body, x, y)
   of tyDistinct:
     if not considerUserDefinedOp(c, t, body, x, y):
-      fillBody(c, t[0], body, x, y)
+      fillBody(c, t.elementType, body, x, y)
   of tyTuple:
     fillBodyTup(c, t, body, x, y)
   of tyVarargs, tyOpenArray:
@@ -1019,7 +1046,7 @@ proc fillBody(c: var TLiftCtx; t: PType; body, x, y: PNode) =
     else:
       discard "cannot copy openArray"
 
-  of tyFromExpr, tyProxy, tyBuiltInTypeClass, tyUserTypeClass,
+  of tyFromExpr, tyError, tyBuiltInTypeClass, tyUserTypeClass,
      tyUserTypeClassInst, tyCompositeTypeClass, tyAnd, tyOr, tyNot, tyAnything,
      tyGenericParam, tyGenericBody, tyNil, tyUntyped, tyTyped,
      tyTypeDesc, tyGenericInvocation, tyForward, tyStatic:
@@ -1027,14 +1054,14 @@ proc fillBody(c: var TLiftCtx; t: PType; body, x, y: PNode) =
     discard
   of tyOrdinal, tyRange, tyInferred,
      tyGenericInst, tyAlias, tySink:
-    fillBody(c, lastSon(t), body, x, y)
-  of tyConcept, tyIterable: doAssert false
+    fillBody(c, skipModifier(t), body, x, y)
+  of tyConcept, tyIterable: raiseAssert "unreachable"
 
 proc produceSymDistinctType(g: ModuleGraph; c: PContext; typ: PType;
                             kind: TTypeAttachedOp; info: TLineInfo;
                             idgen: IdGenerator): PSym =
   assert typ.kind == tyDistinct
-  let baseType = typ[0]
+  let baseType = typ.elementType
   if getAttachedOp(g, baseType, kind) == nil:
     # TODO: fixme `isDistinct` is a fix for #23552; remove it after
     # `-d:nimPreviewNonVarDestructor` becomes the default
@@ -1052,7 +1079,7 @@ proc symDupPrototype(g: ModuleGraph; typ: PType; owner: PSym; kind: TTypeAttache
   res.typ = typ
   src.typ = typ
 
-  result.typ = newType(tyProc, nextTypeId idgen, owner)
+  result.typ = newType(tyProc, idgen, owner)
   result.typ.n = newNodeI(nkFormalParams, info)
   rawAddSon(result.typ, res.typ)
   result.typ.n.add newNodeI(nkEffectList, info)
@@ -1077,7 +1104,7 @@ proc symDupPrototype(g: ModuleGraph; typ: PType; owner: PSym; kind: TTypeAttache
   incl result.flags, sfGeneratedOp
 
 proc symPrototype(g: ModuleGraph; typ: PType; owner: PSym; kind: TTypeAttachedOp;
-              info: TLineInfo; idgen: IdGenerator; isDistinct = false): PSym =
+              info: TLineInfo; idgen: IdGenerator; isDiscriminant = false; isDistinct = false): PSym =
   if kind == attachedDup:
     return symDupPrototype(g, typ, owner, kind, info, idgen)
 
@@ -1087,7 +1114,8 @@ proc symPrototype(g: ModuleGraph; typ: PType; owner: PSym; kind: TTypeAttachedOp
   let src = newSym(skParam, getIdent(g.cache, if kind == attachedTrace: "env" else: "src"),
                    idgen, result, info)
 
-  if kind == attachedDestructor and typ.kind in {tyRef, tyString, tySequence} and g.config.selectedGC in {gcArc, gcOrc, gcAtomicArc} and not isDistinct:
+  if kind == attachedDestructor and g.config.selectedGC in {gcArc, gcOrc, gcAtomicArc} and
+     ((g.config.isDefined("nimPreviewNonVarDestructor") and not isDiscriminant) or (typ.kind in {tyRef, tyString, tySequence} and not isDistinct)):
     dest.typ = typ
   else:
     dest.typ = makeVarType(typ.owner, typ, idgen)
@@ -1097,7 +1125,7 @@ proc symPrototype(g: ModuleGraph; typ: PType; owner: PSym; kind: TTypeAttachedOp
   else:
     src.typ = typ
 
-  result.typ = newProcType(info, nextTypeId(idgen), owner)
+  result.typ = newProcType(info, idgen, owner)
   result.typ.addParam dest
   if kind notin {attachedDestructor, attachedWasMoved}:
     result.typ.addParam src
@@ -1124,8 +1152,8 @@ proc symPrototype(g: ModuleGraph; typ: PType; owner: PSym; kind: TTypeAttachedOp
 proc genTypeFieldCopy(c: var TLiftCtx; t: PType; body, x, y: PNode) =
   let xx = genBuiltin(c, mAccessTypeField, "accessTypeField", x)
   let yy = genBuiltin(c, mAccessTypeField, "accessTypeField", y)
-  xx.typ = getSysType(c.g, c.info, tyPointer)
-  yy.typ = xx.typ
+  xx.typ() = getSysType(c.g, c.info, tyPointer)
+  yy.typ() = xx.typ
   body.add newAsgnStmt(xx, yy)
 
 proc produceSym(g: ModuleGraph; c: PContext; typ: PType; kind: TTypeAttachedOp;
@@ -1141,7 +1169,7 @@ proc produceSym(g: ModuleGraph; c: PContext; typ: PType; kind: TTypeAttachedOp;
                    fn: result)
 
   let dest = if kind == attachedDup: result.ast[resultPos].sym else: result.typ.n[1].sym
-  let d = if result.typ[1].kind == tyVar: newDeref(newSymNode(dest)) else: newSymNode(dest)
+  let d = if result.typ.firstParamType.kind == tyVar: newDeref(newSymNode(dest)) else: newSymNode(dest)
   let src = case kind
             of {attachedDestructor, attachedWasMoved}: newNodeIT(nkSym, info, getSysType(g, info, tyPointer))
             of attachedDup: newSymNode(result.typ.n[1].sym)
@@ -1154,7 +1182,7 @@ proc produceSym(g: ModuleGraph; c: PContext; typ: PType; kind: TTypeAttachedOp;
     ## compiler can use a combination of `=destroy` and memCopy for sink op
     dest.flags.incl sfCursor
     let op = getAttachedOp(g, typ, attachedDestructor)
-    result.ast[bodyPos].add newOpCall(a, op, if op.typ[1].kind == tyVar: d[0] else: d)
+    result.ast[bodyPos].add newOpCall(a, op, if op.typ.firstParamType.kind == tyVar: d[0] else: d)
     result.ast[bodyPos].add newAsgnStmt(d, src)
   else:
     var tk: TTypeKind
@@ -1173,14 +1201,20 @@ proc produceSym(g: ModuleGraph; c: PContext; typ: PType; kind: TTypeAttachedOp;
         # bug #19205: Do not forget to also copy the hidden type field:
         genTypeFieldCopy(a, typ, result.ast[bodyPos], d, src)
 
-  if not a.canRaise: incl result.flags, sfNeverRaises
+  if not a.canRaise:
+    incl result.flags, sfNeverRaises
+    result.ast[pragmasPos] = newNodeI(nkPragma, info)
+    result.ast[pragmasPos].add newTree(nkExprColonExpr,
+        newIdentNode(g.cache.getIdent("raises"),  info), newNodeI(nkBracket, info))
+
   completePartialOp(g, idgen.module, typ, kind, result)
 
 
 proc produceDestructorForDiscriminator*(g: ModuleGraph; typ: PType; field: PSym,
                                         info: TLineInfo; idgen: IdGenerator): PSym =
   assert(typ.skipTypes({tyAlias, tyGenericInst}).kind == tyObject)
-  result = symPrototype(g, field.typ, typ.owner, attachedDestructor, info, idgen)
+  # discrimantor assignments needs pointers to destroy fields; alas, we cannot use non-var destructor here
+  result = symPrototype(g, field.typ, typ.owner, attachedDestructor, info, idgen, isDiscriminant = true)
   var a = TLiftCtx(info: info, g: g, kind: attachedDestructor, asgnForType: typ, idgen: idgen,
                    fn: result)
   a.asgnForType = typ
@@ -1267,7 +1301,7 @@ proc createTypeBoundOps(g: ModuleGraph; c: PContext; orig: PType; info: TLineInf
   # bug #15122: We need to produce all prototypes before entering the
   # mind boggling recursion. Hacks like these imply we should rewrite
   # this module.
-  var generics: array[attachedWasMoved..attachedTrace, bool]
+  var generics: array[attachedWasMoved..attachedTrace, bool] = default(array[attachedWasMoved..attachedTrace, bool])
   for k in attachedWasMoved..lastAttached:
     generics[k] = getAttachedOp(g, canon, k) != nil
     if not generics[k]:

compiler/liftlocals.nim

@@ -10,9 +10,11 @@
 ## This module implements the '.liftLocals' pragma.
 
 import
-  strutils, options, ast, msgs,
+  options, ast, msgs,
   idents, renderer, types, lowerings, lineinfos
 
+import std/strutils
+
 from pragmas import getPragmaVal
 from wordrecg import wLiftLocals
 
@@ -30,12 +32,12 @@ proc interestingVar(s: PSym): bool {.inline.} =
 proc lookupOrAdd(c: var Ctx; s: PSym; info: TLineInfo): PNode =
   let field = addUniqueField(c.objType, s, c.cache, c.idgen)
   var deref = newNodeI(nkHiddenDeref, info)
-  deref.typ = c.objType
+  deref.typ() = c.objType
   deref.add(newSymNode(c.partialParam, info))
   result = newNodeI(nkDotExpr, info)
   result.add(deref)
   result.add(newSymNode(field))
-  result.typ = field.typ
+  result.typ() = field.typ
 
 proc liftLocals(n: PNode; i: int; c: var Ctx) =
   let it = n[i]
@@ -49,6 +51,7 @@ proc liftLocals(n: PNode; i: int; c: var Ctx) =
       liftLocals(it, i, c)
 
 proc lookupParam(params, dest: PNode): PSym =
+  result = nil
   if dest.kind != nkIdent: return nil
   for i in 1..<params.len:
     if params[i].kind == nkSym and params[i].sym.name.id == dest.ident.id:

compiler/lineinfos.nim

@@ -7,10 +7,11 @@
 #    distribution, for details about the copyright.
 #
 
-## This module contains the ``TMsgKind`` enum as well as the
-## ``TLineInfo`` object.
+## This module contains the `TMsgKind` enum as well as the
+## `TLineInfo` object.
 
-import ropes, tables, pathutils, hashes
+import ropes, pathutils
+import std/[hashes, tables]
 
 const
   explanationsBaseUrl* = "https://nim-lang.github.io/Nim"
@@ -91,8 +92,10 @@ type
     warnStmtListLambda = "StmtListLambda",
     warnBareExcept = "BareExcept",
     warnImplicitDefaultValue = "ImplicitDefaultValue",
-    warnGenericsIgnoredInjection = "GenericsIgnoredInjection",
+    warnIgnoredSymbolInjection = "IgnoredSymbolInjection",
+    warnStdPrefix = "StdPrefix"
     warnUser = "User",
+    warnGlobalVarConstructorTemporary = "GlobalVarConstructorTemporary",
     # hints
     hintSuccess = "Success", hintSuccessX = "SuccessX",
     hintCC = "CC",
@@ -105,7 +108,6 @@ type
     hintPattern = "Pattern", hintExecuting = "Exec", hintLinking = "Link", hintDependency = "Dependency",
     hintSource = "Source", hintPerformance = "Performance", hintStackTrace = "StackTrace",
     hintGCStats = "GCStats", hintGlobalVar = "GlobalVar", hintExpandMacro = "ExpandMacro",
-    hintAmbiguousEnum = "AmbiguousEnum",
     hintUser = "User", hintUserRaw = "UserRaw", hintExtendedContext = "ExtendedContext",
     hintMsgOrigin = "MsgOrigin", # since 1.3.5
     hintDeclaredLoc = "DeclaredLoc", # since 1.5.1
@@ -196,8 +198,10 @@ const
     warnStmtListLambda: "statement list expression assumed to be anonymous proc; this is deprecated, use `do (): ...` or `proc () = ...` instead",
     warnBareExcept: "$1",
     warnImplicitDefaultValue: "$1",
-    warnGenericsIgnoredInjection: "$1",
+    warnIgnoredSymbolInjection: "$1",
+    warnStdPrefix: "$1 needs the 'std' prefix",
     warnUser: "$1",
+    warnGlobalVarConstructorTemporary: "global variable '$1' initialization requires a temporary variable",
     hintSuccess: "operation successful: $#",
     # keep in sync with `testament.isSuccess`
     hintSuccessX: "$build\n$loc lines; ${sec}s; $mem; proj: $project; out: $output",
@@ -228,7 +232,6 @@ const
     hintGCStats: "$1",
     hintGlobalVar: "global variable declared here",
     hintExpandMacro: "expanded macro: $1",
-    hintAmbiguousEnum: "$1",
     hintUser: "$1",
     hintUserRaw: "$1",
     hintExtendedContext: "$1",
@@ -252,7 +255,8 @@ type
   TNoteKinds* = set[TNoteKind]
 
 proc computeNotesVerbosity(): array[0..3, TNoteKinds] =
-  result[3] = {low(TNoteKind)..high(TNoteKind)} - {warnObservableStores, warnResultUsed, warnAnyEnumConv, warnBareExcept}
+  result = default(array[0..3, TNoteKinds])
+  result[3] = {low(TNoteKind)..high(TNoteKind)} - {warnObservableStores, warnResultUsed, warnAnyEnumConv, warnBareExcept, warnStdPrefix}
   result[2] = result[3] - {hintStackTrace, hintExtendedContext, hintDeclaredLoc, hintProcessingStmt}
   result[1] = result[2] - {warnProveField, warnProveIndex,
     warnGcUnsafe, hintPath, hintDependency, hintCodeBegin, hintCodeEnd,
@@ -264,6 +268,7 @@ const
   NotesVerbosity* = computeNotesVerbosity()
   errXMustBeCompileTime* = "'$1' can only be used in compile-time context"
   errArgsNeedRunOption* = "arguments can only be given if the '--run' option is selected"
+  errFloatToString* = "cannot convert '$1' to '$2'"
 
 type
   TFileInfo* = object
@@ -314,7 +319,7 @@ proc `==`*(a, b: FileIndex): bool {.borrow.}
 proc hash*(i: TLineInfo): Hash =
   hash (i.line.int, i.col.int, i.fileIndex.int)
 
-proc raiseRecoverableError*(msg: string) {.noinline.} =
+proc raiseRecoverableError*(msg: string) {.noinline, noreturn.} =
   raise newException(ERecoverableError, msg)
 
 const
@@ -345,9 +350,8 @@ type
 
 
 proc initMsgConfig*(): MsgConfig =
-  result.msgContext = @[]
-  result.lastError = unknownLineInfo
-  result.filenameToIndexTbl = initTable[string, FileIndex]()
-  result.fileInfos = @[]
-  result.errorOutputs = {eStdOut, eStdErr}
+  result = MsgConfig(msgContext: @[], lastError: unknownLineInfo,
+                     filenameToIndexTbl: initTable[string, FileIndex](),
+                     fileInfos: @[], errorOutputs: {eStdOut, eStdErr}
+  )
   result.filenameToIndexTbl["???"] = FileIndex(-1)

compiler/linter.nim

@@ -12,17 +12,19 @@
 import std/strutils
 from std/sugar import dup
 
-import options, ast, msgs, idents, lineinfos, wordrecg, astmsgs, semdata, packages
+import options, ast, msgs, idents, lineinfos, wordrecg, astmsgs, semdata, packages, modulegraphs
 export packages
 
 const
   Letters* = {'a'..'z', 'A'..'Z', '0'..'9', '\x80'..'\xFF', '_'}
 
 proc identLen*(line: string, start: int): int =
+  result = 0
   while start+result < line.len and line[start+result] in Letters:
     inc result
 
 proc `=~`(s: string, a: openArray[string]): bool =
+  result = false
   for x in a:
     if s.startsWith(x): return true
 
@@ -95,7 +97,7 @@ template styleCheckDef*(ctx: PContext; info: TLineInfo; sym: PSym; k: TSymKind)
   if optStyleCheck in ctx.config.options and # ignore if styleChecks are off
      {optStyleHint, optStyleError} * ctx.config.globalOptions != {} and # check only if hint/error is enabled
      hintName in ctx.config.notes and # ignore if name checks are not requested
-     ctx.config.belongsToProjectPackage(sym) and # ignore foreign packages
+     ctx.config.belongsToProjectPackageMaybeNil(getModule(ctx.graph, info.fileIndex)) and # ignore foreign packages
      optStyleUsages notin ctx.config.globalOptions and # ignore if requested to only check name usage
      sym.kind != skResult and # ignore `result`
      sym.kind != skTemp and # ignore temporary variables created by the compiler
@@ -136,7 +138,7 @@ template styleCheckUse*(ctx: PContext; info: TLineInfo; sym: PSym) =
   ## Check symbol uses match their definition's style.
   if {optStyleHint, optStyleError} * ctx.config.globalOptions != {} and # ignore if styleChecks are off
      hintName in ctx.config.notes and # ignore if name checks are not requested
-     ctx.config.belongsToProjectPackage(sym) and # ignore foreign packages
+     ctx.config.belongsToProjectPackageMaybeNil(getModule(ctx.graph, info.fileIndex)) and # ignore foreign packages
      sym.kind != skTemp and # ignore temporary variables created by the compiler
      sym.name.s[0] in Letters and # ignore operators TODO: what about unicode symbols???
      sfAnon notin sym.flags: # ignore temporary variables created by the compiler
@@ -152,5 +154,5 @@ template checkPragmaUse*(ctx: PContext; info: TLineInfo; w: TSpecialWord; pragma
   ## Note: This only applies to builtin pragmas, not user pragmas.
   if {optStyleHint, optStyleError} * ctx.config.globalOptions != {} and # ignore if styleChecks are off
      hintName in ctx.config.notes and # ignore if name checks are not requested
-     (sym != nil and ctx.config.belongsToProjectPackage(sym)): # ignore foreign packages
+     ctx.config.belongsToProjectPackageMaybeNil(getModule(ctx.graph, info.fileIndex)): # ignore foreign packages
     checkPragmaUseImpl(ctx.config, info, w, pragmaName)

compiler/llstream.nim

@@ -19,7 +19,7 @@ when defined(nimPreviewSlimSystem):
 const hasRstdin = (defined(nimUseLinenoise) or defined(useLinenoise) or defined(useGnuReadline)) and
   not defined(windows)
 
-when hasRstdin: import rdstdin
+when hasRstdin: import std/rdstdin
 
 type
   TLLRepl* = proc (s: PLLStream, buf: pointer, bufLen: int): int
@@ -40,33 +40,22 @@ type
 
   PLLStream* = ref TLLStream
 
-proc llStreamOpen*(data: string): PLLStream =
-  new(result)
-  result.s = data
-  result.kind = llsString
+proc llStreamOpen*(data: sink string): PLLStream =
+  PLLStream(kind: llsString, s: data)
 
 proc llStreamOpen*(f: File): PLLStream =
-  new(result)
-  result.f = f
-  result.kind = llsFile
+  PLLStream(kind: llsFile, f: f)
 
 proc llStreamOpen*(filename: AbsoluteFile, mode: FileMode): PLLStream =
-  new(result)
-  result.kind = llsFile
+  result = PLLStream(kind: llsFile)
   if not open(result.f, filename.string, mode): result = nil
 
 proc llStreamOpen*(): PLLStream =
-  new(result)
-  result.kind = llsNone
+  PLLStream(kind: llsNone)
 
 proc llReadFromStdin(s: PLLStream, buf: pointer, bufLen: int): int
 proc llStreamOpenStdIn*(r: TLLRepl = llReadFromStdin, onPrompt: OnPrompt = nil): PLLStream =
-  new(result)
-  result.kind = llsStdIn
-  result.s = ""
-  result.lineOffset = -1
-  result.repl = r
-  result.onPrompt = onPrompt
+  PLLStream(kind: llsStdIn, s: "", lineOffset: -1, repl: r, onPrompt: onPrompt)
 
 proc llStreamClose*(s: PLLStream) =
   case s.kind
@@ -79,6 +68,7 @@ when not declared(readLineFromStdin):
   # fallback implementation:
   proc readLineFromStdin(prompt: string, line: var string): bool =
     stdout.write(prompt)
+    stdout.flushFile()
     result = readLine(stdin, line)
     if not result:
       stdout.write("\n")
@@ -89,6 +79,8 @@ proc endsWith*(x: string, s: set[char]): bool =
   while i >= 0 and x[i] == ' ': dec(i)
   if i >= 0 and x[i] in s:
     result = true
+  else:
+    result = false
 
 const
   LineContinuationOprs = {'+', '-', '*', '/', '\\', '<', '>', '!', '?', '^',
@@ -104,6 +96,7 @@ proc continueLine(line: string, inTripleString: bool): bool {.inline.} =
         line.endsWith(LineContinuationOprs+AdditionalLineContinuationOprs))
 
 proc countTriples(s: string): int =
+  result = 0
   var i = 0
   while i+2 < s.len:
     if s[i] == '"' and s[i+1] == '"' and s[i+2] == '"':

compiler/lookups.nim

@@ -14,8 +14,10 @@ when defined(nimPreviewSlimSystem):
   import std/assertions
 
 import
-  intsets, ast, astalgo, idents, semdata, types, msgs, options,
-  renderer, lineinfos, modulegraphs, astmsgs, sets, wordrecg
+  ast, astalgo, idents, semdata, types, msgs, options,
+  renderer, lineinfos, modulegraphs, astmsgs, wordrecg
+
+import std/[intsets, sets]
 
 proc ensureNoMissingOrUnusedSymbols(c: PContext; scope: PScope)
 
@@ -48,7 +50,7 @@ proc considerQuotedIdent*(c: PContext; n: PNode, origin: PNode = nil): PIdent =
         case x.kind
         of nkIdent: id.add(x.ident.s)
         of nkSym: id.add(x.sym.name.s)
-        of nkSymChoices:
+        of nkSymChoices, nkOpenSym:
           if x[0].kind == nkSym:
             id.add(x[0].sym.name.s)
           else:
@@ -61,6 +63,8 @@ proc considerQuotedIdent*(c: PContext; n: PNode, origin: PNode = nil): PIdent =
       result = n[0].sym.name
     else:
       handleError(n, origin)
+  of nkOpenSym:
+    result = considerQuotedIdent(c, n[0], origin)
   else:
     handleError(n, origin)
 
@@ -72,7 +76,7 @@ proc addUniqueSym*(scope: PScope, s: PSym): PSym =
 
 proc openScope*(c: PContext): PScope {.discardable.} =
   result = PScope(parent: c.currentScope,
-                  symbols: newStrTable(),
+                  symbols: initStrTable(),
                   depthLevel: c.scopeDepth + 1)
   c.currentScope = result
 
@@ -135,7 +139,7 @@ proc nextIdentIter(ti: var ModuleIter; marked: var IntSet; im: ImportedModule;
         return result
 
 iterator symbols(im: ImportedModule; marked: var IntSet; name: PIdent; g: ModuleGraph): PSym =
-  var ti: ModuleIter
+  var ti: ModuleIter = default(ModuleIter)
   var candidate = initIdentIter(ti, marked, im, name, g)
   while candidate != nil:
     yield candidate
@@ -148,7 +152,7 @@ iterator importedItems*(c: PContext; name: PIdent): PSym =
       yield s
 
 proc allPureEnumFields(c: PContext; name: PIdent): seq[PSym] =
-  var ti: TIdentIter
+  var ti: TIdentIter = default(TIdentIter)
   result = @[]
   var res = initIdentIter(ti, c.pureEnumFields, name)
   while res != nil:
@@ -220,7 +224,7 @@ proc debugScopes*(c: PContext; limit=0, max = int.high) {.deprecated.} =
 proc searchInScopesAllCandidatesFilterBy*(c: PContext, s: PIdent, filter: TSymKinds): seq[PSym] =
   result = @[]
   for scope in allScopes(c.currentScope):
-    var ti: TIdentIter
+    var ti: TIdentIter = default(TIdentIter)
     var candidate = initIdentIter(ti, scope.symbols, s)
     while candidate != nil:
       if candidate.kind in filter:
@@ -238,7 +242,7 @@ proc searchInScopesFilterBy*(c: PContext, s: PIdent, filter: TSymKinds): seq[PSy
   result = @[]
   block outer:
     for scope in allScopes(c.currentScope):
-      var ti: TIdentIter
+      var ti: TIdentIter = default(TIdentIter)
       var candidate = initIdentIter(ti, scope.symbols, s)
       while candidate != nil:
         if candidate.kind in filter:
@@ -254,11 +258,23 @@ proc searchInScopesFilterBy*(c: PContext, s: PIdent, filter: TSymKinds): seq[PSy
         if s.kind in filter:
           result.add s
 
+proc cmpScopes*(ctx: PContext, s: PSym): int =
+  # Do not return a negative number
+  if s.originatingModule == ctx.module:
+    result = 2
+    var owner = s
+    while true:
+      owner = owner.skipGenericOwner
+      if owner.kind == skModule: break
+      inc result
+  else:
+    result = 1
+
 proc isAmbiguous*(c: PContext, s: PIdent, filter: TSymKinds, sym: var PSym): bool =
   result = false
   block outer:
     for scope in allScopes(c.currentScope):
-      var ti: TIdentIter
+      var ti: TIdentIter = default(TIdentIter)
       var candidate = initIdentIter(ti, scope.symbols, s)
       var scopeHasCandidate = false
       while candidate != nil:
@@ -289,8 +305,16 @@ proc isAmbiguous*(c: PContext, s: PIdent, filter: TSymKinds, sym: var PSym): boo
     # imports had a candidate but wasn't ambiguous
     return false
 
-proc errorSym*(c: PContext, n: PNode): PSym =
+proc errorSym*(c: PContext, ident: PIdent, info: TLineInfo): PSym =
   ## creates an error symbol to avoid cascading errors (for IDE support)
+  result = newSym(skError, ident, c.idgen, getCurrOwner(c), info, {})
+  result.typ = errorType(c)
+  incl(result.flags, sfDiscardable)
+  # pretend it's from the top level scope to prevent cascading errors:
+  if c.config.cmd != cmdInteractive and c.compilesContextId == 0:
+    c.moduleScope.addSym(result)
+
+proc errorSym*(c: PContext, n: PNode): PSym =
   var m = n
   # ensure that 'considerQuotedIdent' can't fail:
   if m.kind == nkDotExpr: m = m[1]
@@ -298,12 +322,7 @@ proc errorSym*(c: PContext, n: PNode): PSym =
       considerQuotedIdent(c, m)
     else:
       getIdent(c.cache, "err:" & renderTree(m))
-  result = newSym(skError, ident, c.idgen, getCurrOwner(c), n.info, {})
-  result.typ = errorType(c)
-  incl(result.flags, sfDiscardable)
-  # pretend it's from the top level scope to prevent cascading errors:
-  if c.config.cmd != cmdInteractive and c.compilesContextId == 0:
-    c.moduleScope.addSym(result)
+  result = errorSym(c, ident, n.info)
 
 type
   TOverloadIterMode* = enum
@@ -330,10 +349,10 @@ proc getSymRepr*(conf: ConfigRef; s: PSym, getDeclarationPath = true): string =
 
 proc ensureNoMissingOrUnusedSymbols(c: PContext; scope: PScope) =
   # check if all symbols have been used and defined:
-  var it: TTabIter
+  var it: TTabIter = default(TTabIter)
   var s = initTabIter(it, scope.symbols)
   var missingImpls = 0
-  var unusedSyms: seq[tuple[sym: PSym, key: string]]
+  var unusedSyms: seq[tuple[sym: PSym, key: string]] = @[]
   while s != nil:
     if sfForward in s.flags and s.kind notin {skType, skModule}:
       # too many 'implementation of X' errors are annoying
@@ -439,7 +458,7 @@ proc openShadowScope*(c: PContext) =
   ## opens a shadow scope, just like any other scope except the depth is the
   ## same as the parent -- see `isShadowScope`.
   c.currentScope = PScope(parent: c.currentScope,
-                          symbols: newStrTable(),
+                          symbols: initStrTable(),
                           depthLevel: c.scopeDepth)
 
 proc closeShadowScope*(c: PContext) =
@@ -464,7 +483,7 @@ proc mergeShadowScope*(c: PContext) =
       c.addInterfaceDecl(sym)
 
 
-import std/editdistance, heapqueue
+import std/[editdistance, heapqueue]
 
 type SpellCandidate = object
   dist: int
@@ -485,7 +504,7 @@ proc mustFixSpelling(c: PContext): bool {.inline.} =
   result = c.config.spellSuggestMax != 0 and c.compilesContextId == 0
     # don't slowdown inside compiles()
 
-proc fixSpelling(c: PContext, n: PNode, ident: PIdent, result: var string) =
+proc fixSpelling(c: PContext, ident: PIdent, result: var string) =
   ## when we cannot find the identifier, suggest nearby spellings
   var list = initHeapQueue[SpellCandidate]()
   let name0 = ident.s.nimIdentNormalize
@@ -493,7 +512,7 @@ proc fixSpelling(c: PContext, n: PNode, ident: PIdent, result: var string) =
   for (sym, depth, isLocal) in allSyms(c):
     let depth = -depth - 1
     let dist = editDistance(name0, sym.name.s.nimIdentNormalize)
-    var msg: string
+    var msg: string = ""
     msg.add "\n ($1, $2): '$3'" % [$dist, $depth, sym.name.s]
     list.push SpellCandidate(dist: dist, depth: depth, msg: msg, sym: sym)
 
@@ -523,6 +542,7 @@ proc errorUseQualifier(c: PContext; info: TLineInfo; s: PSym; amb: var bool): PS
   var err = "ambiguous identifier: '" & s.name.s & "'"
   var i = 0
   var ignoredModules = 0
+  result = nil
   for candidate in importedItems(c, s.name):
     if i == 0: err.add " -- use one of the following:\n"
     else: err.add "\n"
@@ -540,26 +560,36 @@ proc errorUseQualifier(c: PContext; info: TLineInfo; s: PSym; amb: var bool): PS
     amb = false
 
 proc errorUseQualifier*(c: PContext; info: TLineInfo; s: PSym) =
-  var amb: bool
+  var amb: bool = false
   discard errorUseQualifier(c, info, s, amb)
 
-proc errorUseQualifier(c: PContext; info: TLineInfo; candidates: seq[PSym]; prefix = "use one of") =
-  var err = "ambiguous identifier: '" & candidates[0].name.s & "'"
+proc ambiguousIdentifierMsg*(candidates: seq[PSym], prefix = "use one of", indent = 0): string =
+  result = ""
+  for i in 0 ..< indent:
+    result.add(' ')
+  result.add "ambiguous identifier: '" & candidates[0].name.s & "'"
   var i = 0
   for candidate in candidates:
-    if i == 0: err.add " -- $1 the following:\n" % prefix
-    else: err.add "\n"
-    err.add "  " & candidate.owner.name.s & "." & candidate.name.s
-    err.add ": " & typeToString(candidate.typ)
+    if i == 0: result.add " -- $1 the following:\n" % prefix
+    else: result.add "\n"
+    for i in 0 ..< indent:
+      result.add(' ')
+    result.add "  " & candidate.owner.name.s & "." & candidate.name.s
+    result.add ": " & typeToString(candidate.typ)
     inc i
-  localError(c.config, info, errGenerated, err)
 
-proc errorUseQualifier*(c: PContext; info:TLineInfo; choices: PNode) =
+proc errorUseQualifier*(c: PContext; info: TLineInfo; candidates: seq[PSym]) =
+  localError(c.config, info, errGenerated, ambiguousIdentifierMsg(candidates))
+
+proc ambiguousIdentifierMsg*(choices: PNode, indent = 0): string =
   var candidates = newSeq[PSym](choices.len)
   let prefix = if choices[0].typ.kind != tyProc: "use one of" else: "you need a helper proc to disambiguate"
   for i, n in choices:
     candidates[i] = n.sym
-  errorUseQualifier(c, info, candidates, prefix)
+  result = ambiguousIdentifierMsg(candidates, prefix, indent)
+
+proc errorUseQualifier*(c: PContext; info:TLineInfo; choices: PNode) =
+  localError(c.config, info, errGenerated, ambiguousIdentifierMsg(choices))
 
 proc errorUndeclaredIdentifier*(c: PContext; info: TLineInfo; name: string, extra = "") =
   var err: string
@@ -578,11 +608,11 @@ proc errorUndeclaredIdentifier*(c: PContext; info: TLineInfo; name: string, extr
       c.recursiveDep = ""
   localError(c.config, info, errGenerated, err)
 
-proc errorUndeclaredIdentifierHint*(c: PContext; n: PNode, ident: PIdent): PSym =
+proc errorUndeclaredIdentifierHint*(c: PContext; ident: PIdent; info: TLineInfo): PSym =
   var extra = ""
-  if c.mustFixSpelling: fixSpelling(c, n, ident, extra)
-  errorUndeclaredIdentifier(c, n.info, ident.s, extra)
-  result = errorSym(c, n)
+  if c.mustFixSpelling: fixSpelling(c, ident, extra)
+  errorUndeclaredIdentifier(c, info, ident.s, extra)
+  result = errorSym(c, ident, info)
 
 proc lookUp*(c: PContext, n: PNode): PSym =
   # Looks up a symbol. Generates an error in case of nil.
@@ -590,16 +620,16 @@ proc lookUp*(c: PContext, n: PNode): PSym =
   case n.kind
   of nkIdent:
     result = searchInScopes(c, n.ident, amb)
-    if result == nil: result = errorUndeclaredIdentifierHint(c, n, n.ident)
+    if result == nil: result = errorUndeclaredIdentifierHint(c, n.ident, n.info)
   of nkSym:
     result = n.sym
   of nkAccQuoted:
     var ident = considerQuotedIdent(c, n)
     result = searchInScopes(c, ident, amb)
-    if result == nil: result = errorUndeclaredIdentifierHint(c, n, ident)
+    if result == nil: result = errorUndeclaredIdentifierHint(c, ident, n.info)
   else:
     internalError(c.config, n.info, "lookUp")
-    return
+    return nil
   if amb:
     #contains(c.ambiguousSymbols, result.id):
     result = errorUseQualifier(c, n.info, result, amb)
@@ -610,61 +640,78 @@ type
   TLookupFlag* = enum
     checkAmbiguity, checkUndeclared, checkModule, checkPureEnumFields
 
+const allExceptModule = {low(TSymKind)..high(TSymKind)} - {skModule, skPackage}
+
+proc lookUpCandidates*(c: PContext, ident: PIdent, filter: set[TSymKind],
+                       includePureEnum = false): seq[PSym] =
+  result = searchInScopesFilterBy(c, ident, filter)
+  if skEnumField in filter and (result.len == 0 or includePureEnum):
+    result.add allPureEnumFields(c, ident)
+
 proc qualifiedLookUp*(c: PContext, n: PNode, flags: set[TLookupFlag]): PSym =
-  const allExceptModule = {low(TSymKind)..high(TSymKind)} - {skModule, skPackage}
   case n.kind
   of nkIdent, nkAccQuoted:
     var amb = false
     var ident = considerQuotedIdent(c, n)
     if checkModule in flags:
       result = searchInScopes(c, ident, amb)
+      if result == nil:
+        let candidates = allPureEnumFields(c, ident)
+        if candidates.len > 0:
+          result = candidates[0]
+          amb = candidates.len > 1
+          if amb and checkAmbiguity in flags:
+            errorUseQualifier(c, n.info, candidates)
     else:
-      let candidates = searchInScopesFilterBy(c, ident, allExceptModule)
+      let candidates = lookUpCandidates(c, ident, allExceptModule)
       if candidates.len > 0:
         result = candidates[0]
         amb = candidates.len > 1
         if amb and checkAmbiguity in flags:
           errorUseQualifier(c, n.info, candidates)
-    if result == nil:
-      let candidates = allPureEnumFields(c, ident)
-      if candidates.len > 0:
-        result = candidates[0]
-        amb = candidates.len > 1
-        if amb and checkAmbiguity in flags:
-          errorUseQualifier(c, n.info, candidates)
-
+      else:
+        result = nil
     if result == nil and checkUndeclared in flags:
-      result = errorUndeclaredIdentifierHint(c, n, ident)
+      result = errorUndeclaredIdentifierHint(c, ident, n.info)
     elif checkAmbiguity in flags and result != nil and amb:
       result = errorUseQualifier(c, n.info, result, amb)
     c.isAmbiguous = amb
   of nkSym:
     result = n.sym
+  of nkOpenSym:
+    result = qualifiedLookUp(c, n[0], flags)
   of nkDotExpr:
     result = nil
     var m = qualifiedLookUp(c, n[0], (flags * {checkUndeclared}) + {checkModule})
     if m != nil and m.kind == skModule:
       var ident: PIdent = nil
-      if n[1].kind == nkIdent:
-        ident = n[1].ident
-      elif n[1].kind == nkAccQuoted:
+      if n[1].kind == nkAccQuoted:
         ident = considerQuotedIdent(c, n[1])
+      else:
+        # this includes sym and symchoice nodes, but since we are looking in
+        # a module, it shouldn't matter what was captured
+        ident = n[1].getPIdent
       if ident != nil:
         if m == c.module:
-          result = strTableGet(c.topLevelScope.symbols, ident)
+          var ti: TIdentIter = default(TIdentIter)
+          result = initIdentIter(ti, c.topLevelScope.symbols, ident)
+          if result != nil and nextIdentIter(ti, c.topLevelScope.symbols) != nil:
+            # another symbol exists with same name
+            c.isAmbiguous = true
         else:
+          var amb: bool = false
           if c.importModuleLookup.getOrDefault(m.name.id).len > 1:
-            var amb: bool
             result = errorUseQualifier(c, n.info, m, amb)
           else:
-            result = someSym(c.graph, m, ident)
+            result = someSymAmb(c.graph, m, ident, amb)
+            if amb: c.isAmbiguous = true
         if result == nil and checkUndeclared in flags:
-          result = errorUndeclaredIdentifierHint(c, n[1], ident)
+          result = errorUndeclaredIdentifierHint(c, ident, n[1].info)
       elif n[1].kind == nkSym:
         result = n[1].sym
         if result.owner != nil and result.owner != m and checkUndeclared in flags:
           # dotExpr in templates can end up here
-          result = errorUndeclaredIdentifierHint(c, n[1], considerQuotedIdent(c, n[1]))
+          result = errorUndeclaredIdentifierHint(c, result.name, n[1].info)
       elif checkUndeclared in flags and
            n[1].kind notin {nkOpenSymChoice, nkClosedSymChoice}:
         localError(c.config, n[1].info, "identifier expected, but got: " &
@@ -676,10 +723,15 @@ proc qualifiedLookUp*(c: PContext, n: PNode, flags: set[TLookupFlag]): PSym =
     if result != nil and result.kind == skStub: loadStub(result)
 
 proc initOverloadIter*(o: var TOverloadIter, c: PContext, n: PNode): PSym =
+  if n.kind == nkOpenSym:
+    # maybe the logic in semexprs should be mirrored here instead
+    # for now it only seems this is called for `pickSym` in `getTypeIdent` 
+    return initOverloadIter(o, c, n[0])
   o.importIdx = -1
   o.marked = initIntSet()
   case n.kind
   of nkIdent, nkAccQuoted:
+    result = nil
     var ident = considerQuotedIdent(c, n)
     var scope = c.currentScope
     o.mode = oimNoQualifier
@@ -703,6 +755,7 @@ proc initOverloadIter*(o: var TOverloadIter, c: PContext, n: PNode): PSym =
     result = n.sym
     o.mode = oimDone
   of nkDotExpr:
+    result = nil
     o.mode = oimOtherModule
     o.m = qualifiedLookUp(c, n[0], {checkUndeclared, checkModule})
     if o.m != nil and o.m.kind == skModule:
@@ -732,7 +785,7 @@ proc initOverloadIter*(o: var TOverloadIter, c: PContext, n: PNode): PSym =
     o.symChoiceIndex = 1
     o.marked = initIntSet()
     incl(o.marked, result.id)
-  else: discard
+  else: result = nil
   when false:
     if result != nil and result.kind == skStub: loadStub(result)
 
@@ -747,6 +800,7 @@ proc lastOverloadScope*(o: TOverloadIter): int =
   else: result = -1
 
 proc nextOverloadIterImports(o: var TOverloadIter, c: PContext, n: PNode): PSym =
+  result = nil
   assert o.currentScope == nil
   var idx = o.importIdx+1
   o.importIdx = c.imports.len # assume the other imported modules lack this symbol too
@@ -759,6 +813,7 @@ proc nextOverloadIterImports(o: var TOverloadIter, c: PContext, n: PNode): PSym
     inc idx
 
 proc symChoiceExtension(o: var TOverloadIter; c: PContext; n: PNode): PSym =
+  result = nil
   assert o.currentScope == nil
   while o.importIdx < c.imports.len:
     result = initIdentIter(o.mit, o.marked, c.imports[o.importIdx], o.it.name, c.graph)
@@ -821,6 +876,8 @@ proc nextOverloadIter*(o: var TOverloadIter, c: PContext, n: PNode): PSym =
           break
       if result != nil:
         incl o.marked, result.id
+    else:
+      result = nil
   of oimSymChoiceLocalLookup:
     if o.currentScope != nil:
       result = nextIdentExcluding(o.it, o.currentScope.symbols, o.marked)
@@ -844,13 +901,16 @@ proc nextOverloadIter*(o: var TOverloadIter, c: PContext, n: PNode): PSym =
       if result == nil:
         inc o.importIdx
         result = symChoiceExtension(o, c, n)
+    else:
+      result = nil
 
   when false:
     if result != nil and result.kind == skStub: loadStub(result)
 
 proc pickSym*(c: PContext, n: PNode; kinds: set[TSymKind];
               flags: TSymFlags = {}): PSym =
-  var o: TOverloadIter
+  result = nil
+  var o: TOverloadIter = default(TOverloadIter)
   var a = initOverloadIter(o, c, n)
   while a != nil:
     if a.kind in kinds and flags <= a.flags:

compiler/lowerings.nim

@@ -19,7 +19,7 @@ when defined(nimPreviewSlimSystem):
   import std/assertions
 
 proc newDeref*(n: PNode): PNode {.inline.} =
-  result = newNodeIT(nkHiddenDeref, n.info, n.typ[0])
+  result = newNodeIT(nkHiddenDeref, n.info, n.typ.elementType)
   result.add n
 
 proc newTupleAccess*(g: ModuleGraph; tup: PNode, i: int): PNode =
@@ -144,7 +144,7 @@ proc lowerSwap*(g: ModuleGraph; n: PNode; idgen: IdGenerator; owner: PSym): PNod
   result.add newFastAsgnStmt(n[2], tempAsNode)
 
 proc createObj*(g: ModuleGraph; idgen: IdGenerator; owner: PSym, info: TLineInfo; final=true): PType =
-  result = newType(tyObject, nextTypeId(idgen), owner)
+  result = newType(tyObject, idgen, owner)
   if final:
     rawAddSon(result, nil)
     incl result.flags, tfFinal
@@ -174,12 +174,12 @@ proc rawIndirectAccess*(a: PNode; field: PSym; info: TLineInfo): PNode =
   # returns a[].field as a node
   assert field.kind == skField
   var deref = newNodeI(nkHiddenDeref, info)
-  deref.typ = a.typ.skipTypes(abstractInst)[0]
+  deref.typ() = a.typ.skipTypes(abstractInst)[0]
   deref.add a
   result = newNodeI(nkDotExpr, info)
   result.add deref
   result.add newSymNode(field)
-  result.typ = field.typ
+  result.typ() = field.typ
 
 proc rawDirectAccess*(obj, field: PSym): PNode =
   # returns a.field as a node
@@ -187,7 +187,7 @@ proc rawDirectAccess*(obj, field: PSym): PNode =
   result = newNodeI(nkDotExpr, field.info)
   result.add newSymNode(obj)
   result.add newSymNode(field)
-  result.typ = field.typ
+  result.typ() = field.typ
 
 proc lookupInRecord(n: PNode, id: ItemId): PSym =
   result = nil
@@ -250,19 +250,19 @@ proc newDotExpr*(obj, b: PSym): PNode =
   assert field != nil, b.name.s
   result.add newSymNode(obj)
   result.add newSymNode(field)
-  result.typ = field.typ
+  result.typ() = field.typ
 
 proc indirectAccess*(a: PNode, b: ItemId, info: TLineInfo): PNode =
   # returns a[].b as a node
   var deref = newNodeI(nkHiddenDeref, info)
-  deref.typ = a.typ.skipTypes(abstractInst)[0]
+  deref.typ() = a.typ.skipTypes(abstractInst).elementType
   var t = deref.typ.skipTypes(abstractInst)
   var field: PSym
   while true:
     assert t.kind == tyObject
     field = lookupInRecord(t.n, b)
     if field != nil: break
-    t = t[0]
+    t = t.baseClass
     if t == nil: break
     t = t.skipTypes(skipPtrs)
   #if field == nil:
@@ -273,12 +273,12 @@ proc indirectAccess*(a: PNode, b: ItemId, info: TLineInfo): PNode =
   result = newNodeI(nkDotExpr, info)
   result.add deref
   result.add newSymNode(field)
-  result.typ = field.typ
+  result.typ() = field.typ
 
 proc indirectAccess*(a: PNode, b: string, info: TLineInfo; cache: IdentCache): PNode =
   # returns a[].b as a node
   var deref = newNodeI(nkHiddenDeref, info)
-  deref.typ = a.typ.skipTypes(abstractInst)[0]
+  deref.typ() = a.typ.skipTypes(abstractInst).elementType
   var t = deref.typ.skipTypes(abstractInst)
   var field: PSym
   let bb = getIdent(cache, b)
@@ -286,7 +286,7 @@ proc indirectAccess*(a: PNode, b: string, info: TLineInfo; cache: IdentCache): P
     assert t.kind == tyObject
     field = getSymFromList(t.n, bb)
     if field != nil: break
-    t = t[0]
+    t = t.baseClass
     if t == nil: break
     t = t.skipTypes(skipPtrs)
   #if field == nil:
@@ -297,7 +297,7 @@ proc indirectAccess*(a: PNode, b: string, info: TLineInfo; cache: IdentCache): P
   result = newNodeI(nkDotExpr, info)
   result.add deref
   result.add newSymNode(field)
-  result.typ = field.typ
+  result.typ() = field.typ
 
 proc getFieldFromObj*(t: PType; v: PSym): PSym =
   assert v.kind != skField
@@ -306,7 +306,7 @@ proc getFieldFromObj*(t: PType; v: PSym): PSym =
     assert t.kind == tyObject
     result = lookupInRecord(t.n, v.itemId)
     if result != nil: break
-    t = t[0]
+    t = t.baseClass
     if t == nil: break
     t = t.skipTypes(skipPtrs)
 
@@ -320,12 +320,12 @@ proc indirectAccess*(a, b: PSym, info: TLineInfo): PNode =
 proc genAddrOf*(n: PNode; idgen: IdGenerator; typeKind = tyPtr): PNode =
   result = newNodeI(nkAddr, n.info, 1)
   result[0] = n
-  result.typ = newType(typeKind, nextTypeId(idgen), n.typ.owner)
+  result.typ() = newType(typeKind, idgen, n.typ.owner)
   result.typ.rawAddSon(n.typ)
 
 proc genDeref*(n: PNode; k = nkHiddenDeref): PNode =
   result = newNodeIT(k, n.info,
-                     n.typ.skipTypes(abstractInst)[0])
+                     n.typ.skipTypes(abstractInst).elementType)
   result.add n
 
 proc callCodegenProc*(g: ModuleGraph; name: string;
@@ -344,18 +344,18 @@ proc callCodegenProc*(g: ModuleGraph; name: string;
     if optionalArgs != nil:
       for i in 1..<optionalArgs.len-2:
         result.add optionalArgs[i]
-    result.typ = sym.typ[0]
+    result.typ() = sym.typ.returnType
 
 proc newIntLit*(g: ModuleGraph; info: TLineInfo; value: BiggestInt): PNode =
   result = nkIntLit.newIntNode(value)
-  result.typ = getSysType(g, info, tyInt)
+  result.typ() = getSysType(g, info, tyInt)
 
 proc genHigh*(g: ModuleGraph; n: PNode): PNode =
   if skipTypes(n.typ, abstractVar).kind == tyArray:
     result = newIntLit(g, n.info, toInt64(lastOrd(g.config, skipTypes(n.typ, abstractVar))))
   else:
     result = newNodeI(nkCall, n.info, 2)
-    result.typ = getSysType(g, n.info, tyInt)
+    result.typ() = getSysType(g, n.info, tyInt)
     result[0] = newSymNode(getSysMagic(g, n.info, "high", mHigh))
     result[1] = n
 
@@ -364,7 +364,7 @@ proc genLen*(g: ModuleGraph; n: PNode): PNode =
     result = newIntLit(g, n.info, toInt64(lastOrd(g.config, skipTypes(n.typ, abstractVar)) + 1))
   else:
     result = newNodeI(nkCall, n.info, 2)
-    result.typ = getSysType(g, n.info, tyInt)
+    result.typ() = getSysType(g, n.info, tyInt)
     result[0] = newSymNode(getSysMagic(g, n.info, "len", mLengthSeq))
     result[1] = n
 

compiler/magicsys.nim

@@ -18,7 +18,7 @@ export createMagic
 proc nilOrSysInt*(g: ModuleGraph): PType = g.sysTypes[tyInt]
 
 proc newSysType(g: ModuleGraph; kind: TTypeKind, size: int): PType =
-  result = newType(kind, nextTypeId(g.idgen), g.systemModule)
+  result = newType(kind, g.idgen, g.systemModule)
   result.size = size
   result.align = size.int16
 
@@ -27,19 +27,20 @@ proc getSysSym*(g: ModuleGraph; info: TLineInfo; name: string): PSym =
   if result == nil:
     localError(g.config, info, "system module needs: " & name)
     result = newSym(skError, getIdent(g.cache, name), g.idgen, g.systemModule, g.systemModule.info, {})
-    result.typ = newType(tyError, nextTypeId(g.idgen), g.systemModule)
+    result.typ = newType(tyError, g.idgen, g.systemModule)
 
 proc getSysMagic*(g: ModuleGraph; info: TLineInfo; name: string, m: TMagic): PSym =
+  result = nil
   let id = getIdent(g.cache, name)
   for r in systemModuleSyms(g, id):
     if r.magic == m:
       # prefer the tyInt variant:
-      if r.typ[0] != nil and r.typ[0].kind == tyInt: return r
+      if r.typ.returnType != nil and r.typ.returnType.kind == tyInt: return r
       result = r
   if result != nil: return result
   localError(g.config, info, "system module needs: " & name)
   result = newSym(skError, id, g.idgen, g.systemModule, g.systemModule.info, {})
-  result.typ = newType(tyError, nextTypeId(g.idgen), g.systemModule)
+  result.typ = newType(tyError, g.idgen, g.systemModule)
 
 proc sysTypeFromName*(g: ModuleGraph; info: TLineInfo; name: string): PType =
   result = getSysSym(g, info, name).typ
@@ -80,8 +81,8 @@ proc getSysType*(g: ModuleGraph; info: TLineInfo; kind: TTypeKind): PType =
 
 proc resetSysTypes*(g: ModuleGraph) =
   g.systemModule = nil
-  initStrTable(g.compilerprocs)
-  initStrTable(g.exposed)
+  g.compilerprocs = initStrTable()
+  g.exposed = initStrTable()
   for i in low(g.sysTypes)..high(g.sysTypes):
     g.sysTypes[i] = nil
 
@@ -92,16 +93,23 @@ proc getFloatLitType*(g: ModuleGraph; literal: PNode): PType =
 
 proc skipIntLit*(t: PType; id: IdGenerator): PType {.inline.} =
   if t.n != nil and t.kind in {tyInt, tyFloat}:
-    result = copyType(t, nextTypeId(id), t.owner)
+    result = copyType(t, id, t.owner)
     result.n = nil
   else:
     result = t
 
 proc addSonSkipIntLit*(father, son: PType; id: IdGenerator) =
   let s = son.skipIntLit(id)
-  father.sons.add(s)
+  father.add(s)
   propagateToOwner(father, s)
 
+proc makeVarType*(owner: PSym; baseType: PType; idgen: IdGenerator; kind = tyVar): PType =
+  if baseType.kind == kind:
+    result = baseType
+  else:
+    result = newType(kind, idgen, owner)
+    addSonSkipIntLit(result, baseType, idgen)
+
 proc getCompilerProc*(g: ModuleGraph; name: string): PSym =
   let ident = getIdent(g.cache, name)
   result = strTableGet(g.compilerprocs, ident)
@@ -123,7 +131,7 @@ proc registerNimScriptSymbol*(g: ModuleGraph; s: PSym) =
 proc getNimScriptSymbol*(g: ModuleGraph; name: string): PSym =
   strTableGet(g.exposed, getIdent(g.cache, name))
 
-proc resetNimScriptSymbols*(g: ModuleGraph) = initStrTable(g.exposed)
+proc resetNimScriptSymbols*(g: ModuleGraph) = g.exposed = initStrTable()
 
 proc getMagicEqSymForType*(g: ModuleGraph; t: PType; info: TLineInfo): PSym =
   case t.kind
@@ -145,7 +153,17 @@ proc getMagicEqSymForType*(g: ModuleGraph; t: PType; info: TLineInfo): PSym =
   of tyProc:
     result = getSysMagic(g, info, "==", mEqProc)
   else:
+    result = nil
     globalError(g.config, info,
       "can't find magic equals operator for type kind " & $t.kind)
 
+proc makePtrType*(baseType: PType; idgen: IdGenerator): PType =
+  result = newType(tyPtr, idgen, baseType.owner)
+  addSonSkipIntLit(result, baseType, idgen)
 
+proc makeAddr*(n: PNode; idgen: IdGenerator): PNode =
+  if n.kind == nkHiddenAddr:
+    result = n
+  else:
+    result = newTree(nkHiddenAddr, n)
+    result.typ() = makePtrType(n.typ, idgen)

compiler/main.nim

@@ -26,8 +26,7 @@ import
 when defined(nimPreviewSlimSystem):
   import std/[syncio, assertions]
 
-import ic / [cbackend, integrity, navigator]
-from ic / ic import rodViewer
+import ic / [cbackend, integrity, navigator, ic]
 
 import ../dist/checksums/src/checksums/sha1
 
@@ -56,7 +55,7 @@ proc writeCMakeDepsFile(conf: ConfigRef) =
   for it in conf.toCompile: cfiles.add(it.cname.string)
   let fileset = cfiles.toCountTable()
   # read old cfiles list
-  var fl: File
+  var fl: File = default(File)
   var prevset = initCountTable[string]()
   if open(fl, fname.string, fmRead):
     for line in fl.lines: prevset.inc(line)
@@ -115,7 +114,7 @@ when not defined(leanCompiler):
       setPipeLinePass(graph, Docgen2JsonPass)
     of HtmlExt:
       setPipeLinePass(graph, Docgen2Pass)
-    else: doAssert false, $ext
+    else: raiseAssert $ext
     compilePipelineProject(graph)
 
 proc commandCompileToC(graph: ModuleGraph) =
@@ -195,9 +194,8 @@ proc commandScan(cache: IdentCache, config: ConfigRef) =
   var stream = llStreamOpen(f, fmRead)
   if stream != nil:
     var
-      L: Lexer
-      tok: Token
-    initToken(tok)
+      L: Lexer = default(Lexer)
+      tok: Token = default(Token)
     openLexer(L, f, stream, cache, config)
     while true:
       rawGetTok(L, tok)
@@ -267,7 +265,7 @@ proc mainCommand*(graph: ModuleGraph) =
         # and it has added this define implictly, so we must undo that here.
         # A better solution might be to fix system.nim
         undefSymbol(conf.symbols, "useNimRtl")
-    of backendInvalid: doAssert false
+    of backendInvalid: raiseAssert "unreachable"
 
   proc compileToBackend() =
     customizeForBackend(conf.backend)
@@ -277,7 +275,7 @@ proc mainCommand*(graph: ModuleGraph) =
     of backendCpp: commandCompileToC(graph)
     of backendObjc: commandCompileToC(graph)
     of backendJs: commandCompileToJS(graph)
-    of backendInvalid: doAssert false
+    of backendInvalid: raiseAssert "unreachable"
 
   template docLikeCmd(body) =
     when defined(leanCompiler):
@@ -297,14 +295,18 @@ proc mainCommand*(graph: ModuleGraph) =
     # so by default should not end up in $PWD nor in $projectPath.
     var ret = if optUseNimcache in conf.globalOptions: getNimcacheDir(conf)
               else: conf.projectPath
-    doAssert ret.string.isAbsolute # `AbsoluteDir` is not a real guarantee
+    if not ret.string.isAbsolute: # `AbsoluteDir` is not a real guarantee
+      rawMessage(conf, errCannotOpenFile, ret.string & "/")
     if conf.cmd in cmdDocLike + {cmdRst2html, cmdRst2tex, cmdMd2html, cmdMd2tex}:
       ret = ret / htmldocsDir
     conf.outDir = ret
 
   ## process all commands
   case conf.cmd
-  of cmdBackends: compileToBackend()
+  of cmdBackends:
+    compileToBackend()
+    when BenchIC:
+      echoTimes graph.packed
   of cmdTcc:
     when hasTinyCBackend:
       extccomp.setCC(conf, "tcc", unknownLineInfo)
@@ -400,6 +402,10 @@ proc mainCommand*(graph: ModuleGraph) =
       for it in conf.searchPaths: msgWriteln(conf, it.string)
   of cmdCheck:
     commandCheck(graph)
+  of cmdM:
+    graph.config.symbolFiles = v2Sf
+    setUseIc(graph.config.symbolFiles != disabledSf)
+    commandCheck(graph)
   of cmdParse:
     wantMainModule(conf)
     discard parseFile(conf.projectMainIdx, cache, conf)

compiler/mangleutils.nim

@@ -0,0 +1,59 @@
+import std/strutils
+import ast, modulegraphs
+
+proc mangle*(name: string): string =
+  result = newStringOfCap(name.len)
+  var start = 0
+  if name[0] in Digits:
+    result.add("X" & name[0])
+    start = 1
+  var requiresUnderscore = false
+  template special(x) =
+    result.add x
+    requiresUnderscore = true
+  for i in start..<name.len:
+    let c = name[i]
+    case c
+    of 'a'..'z', '0'..'9', 'A'..'Z':
+      result.add(c)
+    of '_':
+      # we generate names like 'foo_9' for scope disambiguations and so
+      # disallow this here:
+      if i > 0 and i < name.len-1 and name[i+1] in Digits:
+        discard
+      else:
+        result.add(c)
+    of '$': special "dollar"
+    of '%': special "percent"
+    of '&': special "amp"
+    of '^': special "roof"
+    of '!': special "emark"
+    of '?': special "qmark"
+    of '*': special "star"
+    of '+': special "plus"
+    of '-': special "minus"
+    of '/': special "slash"
+    of '\\': special "backslash"
+    of '=': special "eq"
+    of '<': special "lt"
+    of '>': special "gt"
+    of '~': special "tilde"
+    of ':': special "colon"
+    of '.': special "dot"
+    of '@': special "at"
+    of '|': special "bar"
+    else:
+      result.add("X" & toHex(ord(c), 2))
+      requiresUnderscore = true
+  if requiresUnderscore:
+    result.add "_"
+
+proc mangleParamExt*(s: PSym): string =
+  result = "_p"
+  result.addInt s.position
+
+proc mangleProcNameExt*(graph: ModuleGraph, s: PSym): string =
+  result = "__"
+  result.add graph.ifaces[s.itemId.module].uniqueName
+  result.add "_u"
+  result.addInt s.itemId.item # s.disamb #

compiler/modulegraphs.nim

@@ -11,11 +11,12 @@
 ## represents a complete Nim project. Single modules can either be kept in RAM
 ## or stored in a rod-file.
 
-import std/[intsets, tables, hashes, strtabs]
+import std/[intsets, tables, hashes, strtabs, algorithm, os, strutils, parseutils]
 import ../dist/checksums/src/checksums/md5
-import ast, astalgo, options, lineinfos,idents, btrees, ropes, msgs, pathutils, packages
+import ast, astalgo, options, lineinfos,idents, btrees, ropes, msgs, pathutils, packages, suggestsymdb
 import ic / [packed_ast, ic]
 
+
 when defined(nimPreviewSlimSystem):
   import std/assertions
 
@@ -54,11 +55,6 @@ type
     concreteTypes*: seq[FullId]
     inst*: PInstantiation
 
-  SymInfoPair* = object
-    sym*: PSym
-    info*: TLineInfo
-    isDecl*: bool
-
   PipelinePass* = enum
     NonePass
     SemPass
@@ -79,8 +75,9 @@ type
     typeInstCache*: Table[ItemId, seq[LazyType]] # A symbol's ItemId.
     procInstCache*: Table[ItemId, seq[LazyInstantiation]] # A symbol's ItemId.
     attachedOps*: array[TTypeAttachedOp, Table[ItemId, LazySym]] # Type ID, destructors, etc.
-    methodsPerType*: Table[ItemId, seq[(int, LazySym)]] # Type ID, attached methods
-    memberProcsPerType*: Table[ItemId, seq[PSym]] # Type ID, attached member procs (only c++, virtual and ctor so far)
+    methodsPerGenericType*: Table[ItemId, seq[(int, LazySym)]] # Type ID, attached methods
+    memberProcsPerType*: Table[ItemId, seq[PSym]] # Type ID, attached member procs (only c++, virtual,member and ctor so far).
+    initializersPerType*: Table[ItemId, PNode] # Type ID, AST call to the default ctor (c++ only)
     enumToStringProcs*: Table[ItemId, LazySym]
     emittedTypeInfo*: Table[string, FileIndex]
 
@@ -90,6 +87,8 @@ type
     importDeps*: Table[FileIndex, seq[FileIndex]] # explicit import module dependencies
     suggestMode*: bool # whether we are in nimsuggest mode or not.
     invalidTransitiveClosure: bool
+    interactive*: bool
+    withinSystem*: bool # in system.nim or a module imported by system.nim
     inclToMod*: Table[FileIndex, FileIndex] # mapping of include file to the
                                             # first module that included it
     importStack*: seq[FileIndex]  # The current import stack. Used for detecting recursive
@@ -99,12 +98,18 @@ type
     cache*: IdentCache
     vm*: RootRef # unfortunately the 'vm' state is shared project-wise, this will
                  # be clarified in later compiler implementations.
+    repl*: RootRef # REPL state is shared project-wise.
     doStopCompile*: proc(): bool {.closure.}
     usageSym*: PSym # for nimsuggest
     owners*: seq[PSym]
-    suggestSymbols*: Table[FileIndex, seq[SymInfoPair]]
+    suggestSymbols*: SuggestSymbolDatabase
     suggestErrors*: Table[FileIndex, seq[Suggest]]
     methods*: seq[tuple[methods: seq[PSym], dispatcher: PSym]] # needs serialization!
+    bucketTable*: CountTable[ItemId]
+    objectTree*: Table[ItemId, seq[tuple[depth: int, value: PType]]]
+    methodsPerType*: Table[ItemId, seq[LazySym]]
+    dispatchers*: seq[LazySym]
+
     systemModule*: PSym
     sysTypes*: array[TTypeKind, PType]
     compilerprocs*: TStrTable
@@ -145,13 +150,15 @@ type
                  isFrontend: bool]
 
 proc resetForBackend*(g: ModuleGraph) =
-  initStrTable(g.compilerprocs)
+  g.compilerprocs = initStrTable()
   g.typeInstCache.clear()
   g.procInstCache.clear()
   for a in mitems(g.attachedOps):
     a.clear()
-  g.methodsPerType.clear()
+  g.methodsPerGenericType.clear()
   g.enumToStringProcs.clear()
+  g.dispatchers.setLen(0)
+  g.methodsPerType.clear()
 
 const
   cb64 = [
@@ -199,8 +206,8 @@ template semtabAll*(g: ModuleGraph, m: PSym): TStrTable =
   g.ifaces[m.position].interfHidden
 
 proc initStrTables*(g: ModuleGraph, m: PSym) =
-  initStrTable(semtab(g, m))
-  initStrTable(semtabAll(g, m))
+  semtab(g, m) = initStrTable()
+  semtabAll(g, m) = initStrTable()
 
 proc strTableAdds*(g: ModuleGraph, m: PSym, s: PSym) =
   strTableAdd(semtab(g, m), s)
@@ -209,10 +216,10 @@ proc strTableAdds*(g: ModuleGraph, m: PSym, s: PSym) =
 proc isCachedModule(g: ModuleGraph; module: int): bool {.inline.} =
   result = module < g.packed.len and g.packed[module].status == loaded
 
-proc isCachedModule(g: ModuleGraph; m: PSym): bool {.inline.} =
+proc isCachedModule*(g: ModuleGraph; m: PSym): bool {.inline.} =
   isCachedModule(g, m.position)
 
-proc simulateCachedModule*(g: ModuleGraph; moduleSym: PSym; m: PackedModule) =
+proc simulateCachedModule(g: ModuleGraph; moduleSym: PSym; m: PackedModule) =
   when false:
     echo "simulating ", moduleSym.name.s, " ", moduleSym.position
   simulateLoadedModule(g.packed, g.config, g.cache, moduleSym, m)
@@ -251,7 +258,7 @@ proc nextModuleIter*(mi: var ModuleIter; g: ModuleGraph): PSym =
 iterator allSyms*(g: ModuleGraph; m: PSym): PSym =
   let importHidden = optImportHidden in m.options
   if isCachedModule(g, m):
-    var rodIt: RodIter
+    var rodIt: RodIter = default(RodIter)
     var r = initRodIterAllSyms(rodIt, g.config, g.cache, g.packed, FileIndex m.position, importHidden)
     while r != nil:
       yield r
@@ -268,11 +275,30 @@ proc someSym*(g: ModuleGraph; m: PSym; name: PIdent): PSym =
   else:
     result = strTableGet(g.ifaces[m.position].interfSelect(importHidden), name)
 
+proc someSymAmb*(g: ModuleGraph; m: PSym; name: PIdent; amb: var bool): PSym =
+  let importHidden = optImportHidden in m.options
+  if isCachedModule(g, m):
+    result = nil
+    for s in interfaceSymbols(g.config, g.cache, g.packed, FileIndex(m.position), name, importHidden):
+      if result == nil:
+        # set result to the first symbol
+        result = s
+      else:
+        # another symbol found
+        amb = true
+        break
+  else:
+    var ti: TIdentIter = default(TIdentIter)
+    result = initIdentIter(ti, g.ifaces[m.position].interfSelect(importHidden), name)
+    if result != nil and nextIdentIter(ti, g.ifaces[m.position].interfSelect(importHidden)) != nil:
+      # another symbol exists with same name
+      amb = true
+
 proc systemModuleSym*(g: ModuleGraph; name: PIdent): PSym =
   result = someSym(g, g.systemModule, name)
 
 iterator systemModuleSyms*(g: ModuleGraph; name: PIdent): PSym =
-  var mi: ModuleIter
+  var mi: ModuleIter = default(ModuleIter)
   var r = initModuleIter(mi, g, g.systemModule, name)
   while r != nil:
     yield r
@@ -303,7 +329,7 @@ proc resolveInst(g: ModuleGraph; t: var LazyInstantiation): PInstantiation =
     t.inst = result
   assert result != nil
 
-proc resolveAttachedOp(g: ModuleGraph; t: var LazySym): PSym =
+proc resolveAttachedOp*(g: ModuleGraph; t: var LazySym): PSym =
   result = t.sym
   if result == nil:
     result = loadSymFromId(g.config, g.cache, g.packed, t.id.module, t.id.packed)
@@ -322,6 +348,7 @@ iterator procInstCacheItems*(g: ModuleGraph; s: PSym): PInstantiation =
     for t in mitems(x[]):
       yield resolveInst(g, t)
 
+
 proc getAttachedOp*(g: ModuleGraph; t: PType; op: TTypeAttachedOp): PSym =
   ## returns the requested attached operation for type `t`. Can return nil
   ## if no such operation exists.
@@ -345,6 +372,27 @@ proc completePartialOp*(g: ModuleGraph; module: int; t: PType; op: TTypeAttached
     toPackedGeneratedProcDef(value, g.encoders[module], g.packed[module].fromDisk)
     #storeAttachedProcDef(t, op, value, g.encoders[module], g.packed[module].fromDisk)
 
+iterator getDispatchers*(g: ModuleGraph): PSym =
+  for i in g.dispatchers.mitems:
+    yield resolveSym(g, i)
+
+proc addDispatchers*(g: ModuleGraph, value: PSym) =
+  # TODO: add it for packed modules
+  g.dispatchers.add LazySym(sym: value)
+
+iterator resolveLazySymSeq(g: ModuleGraph, list: var seq[LazySym]): PSym =
+  for it in list.mitems:
+    yield resolveSym(g, it)
+
+proc setMethodsPerType*(g: ModuleGraph; id: ItemId, methods: seq[LazySym]) =
+  # TODO: add it for packed modules
+  g.methodsPerType[id] = methods
+
+iterator getMethodsPerType*(g: ModuleGraph; t: PType): PSym =
+  if g.methodsPerType.contains(t.itemId):
+    for it in mitems g.methodsPerType[t.itemId]:
+      yield resolveSym(g, it)
+
 proc getToStringProc*(g: ModuleGraph; t: PType): PSym =
   result = resolveSym(g, g.enumToStringProcs[t.itemId])
   assert result != nil
@@ -353,12 +401,12 @@ proc setToStringProc*(g: ModuleGraph; t: PType; value: PSym) =
   g.enumToStringProcs[t.itemId] = LazySym(sym: value)
 
 iterator methodsForGeneric*(g: ModuleGraph; t: PType): (int, PSym) =
-  if g.methodsPerType.contains(t.itemId):
-    for it in mitems g.methodsPerType[t.itemId]:
+  if g.methodsPerGenericType.contains(t.itemId):
+    for it in mitems g.methodsPerGenericType[t.itemId]:
       yield (it[0], resolveSym(g, it[1]))
 
 proc addMethodToGeneric*(g: ModuleGraph; module: int; t: PType; col: int; m: PSym) =
-  g.methodsPerType.mgetOrPut(t.itemId, @[]).add (col, LazySym(sym: m))
+  g.methodsPerGenericType.mgetOrPut(t.itemId, @[]).add (col, LazySym(sym: m))
 
 proc hasDisabledAsgn*(g: ModuleGraph; t: PType): bool =
   let op = getAttachedOp(g, t, attachedAsgn)
@@ -371,10 +419,11 @@ proc copyTypeProps*(g: ModuleGraph; module: int; dest, src: PType) =
       setAttachedOp(g, module, dest, k, op)
 
 proc loadCompilerProc*(g: ModuleGraph; name: string): PSym =
+  result = nil
   if g.config.symbolFiles == disabledSf: return nil
 
   # slow, linear search, but the results are cached:
-  for module in 0..high(g.packed):
+  for module in 0..<len(g.packed):
     #if isCachedModule(g, module):
     let x = searchForCompilerproc(g.packed[module], name)
     if x >= 0:
@@ -423,6 +472,49 @@ proc createMagic*(g: ModuleGraph; idgen: IdGenerator; name: string, m: TMagic):
 proc createMagic(g: ModuleGraph; name: string, m: TMagic): PSym =
   result = createMagic(g, g.idgen, name, m)
 
+proc uniqueModuleName*(conf: ConfigRef; m: PSym): string =
+  ## The unique module name is guaranteed to only contain {'A'..'Z', 'a'..'z', '0'..'9', '_'}
+  ## so that it is useful as a C identifier snippet.
+  let fid = FileIndex(m.position)
+  let path = AbsoluteFile toFullPath(conf, fid)
+  var isLib = false
+  var rel = ""
+  if path.string.startsWith(conf.libpath.string):
+    isLib = true
+    rel = relativeTo(path, conf.libpath).string
+  else:
+    rel = relativeTo(path, conf.projectPath).string
+
+  if not isLib and not belongsToProjectPackage(conf, m):
+    # special handlings for nimble packages
+    when DirSep == '\\':
+      let rel2 = replace(rel, '\\', '/')
+    else:
+      let rel2 = rel
+    const pkgs2 = "pkgs2/"
+    var start = rel2.find(pkgs2)
+    if start >= 0:
+      start += pkgs2.len
+      start += skipUntil(rel2, {'/'}, start)
+      if start+1 < rel2.len:
+        rel = "pkg/" & rel2[start+1..<rel.len] # strips paths
+
+  let trunc = if rel.endsWith(".nim"): rel.len - len(".nim") else: rel.len
+  result = newStringOfCap(trunc)
+  for i in 0..<trunc:
+    let c = rel[i]
+    case c
+    of 'a'..'z', '0'..'9':
+      result.add c
+    of {os.DirSep, os.AltSep}:
+      result.add 'Z' # because it looks a bit like '/'
+    of '.':
+      result.add 'O' # a circle
+    else:
+      # We mangle upper letters too so that there cannot
+      # be clashes with our special meanings of 'Z' and 'O'
+      result.addInt ord(c)
+
 proc registerModule*(g: ModuleGraph; m: PSym) =
   assert m != nil
   assert m.kind == skModule
@@ -431,10 +523,10 @@ proc registerModule*(g: ModuleGraph; m: PSym) =
     setLen(g.ifaces, m.position + 1)
 
   if m.position >= g.packed.len:
-    setLen(g.packed, m.position + 1)
+    setLen(g.packed.pm, m.position + 1)
 
   g.ifaces[m.position] = Iface(module: m, converters: @[], patterns: @[],
-                               uniqueName: rope(uniqueModuleName(g.config, FileIndex(m.position))))
+                               uniqueName: rope(uniqueModuleName(g.config, m)))
   initStrTables(g, m)
 
 proc registerModuleById*(g: ModuleGraph; m: FileIndex) =
@@ -443,37 +535,39 @@ proc registerModuleById*(g: ModuleGraph; m: FileIndex) =
 proc initOperators*(g: ModuleGraph): Operators =
   # These are safe for IC.
   # Public because it's used by DrNim.
-  result.opLe = createMagic(g, "<=", mLeI)
-  result.opLt = createMagic(g, "<", mLtI)
-  result.opAnd = createMagic(g, "and", mAnd)
-  result.opOr = createMagic(g, "or", mOr)
-  result.opIsNil = createMagic(g, "isnil", mIsNil)
-  result.opEq = createMagic(g, "==", mEqI)
-  result.opAdd = createMagic(g, "+", mAddI)
-  result.opSub = createMagic(g, "-", mSubI)
-  result.opMul = createMagic(g, "*", mMulI)
-  result.opDiv = createMagic(g, "div", mDivI)
-  result.opLen = createMagic(g, "len", mLengthSeq)
-  result.opNot = createMagic(g, "not", mNot)
-  result.opContains = createMagic(g, "contains", mInSet)
+  result = Operators(
+    opLe: createMagic(g, "<=", mLeI),
+    opLt: createMagic(g, "<", mLtI),
+    opAnd: createMagic(g, "and", mAnd),
+    opOr: createMagic(g, "or", mOr),
+    opIsNil: createMagic(g, "isnil", mIsNil),
+    opEq: createMagic(g, "==", mEqI),
+    opAdd: createMagic(g, "+", mAddI),
+    opSub: createMagic(g, "-", mSubI),
+    opMul: createMagic(g, "*", mMulI),
+    opDiv: createMagic(g, "div", mDivI),
+    opLen: createMagic(g, "len", mLengthSeq),
+    opNot: createMagic(g, "not", mNot),
+    opContains: createMagic(g, "contains", mInSet)
+  )
 
 proc initModuleGraphFields(result: ModuleGraph) =
   # A module ID of -1 means that the symbol is not attached to a module at all,
   # but to the module graph:
   result.idgen = IdGenerator(module: -1'i32, symId: 0'i32, typeId: 0'i32)
-  initStrTable(result.packageSyms)
+  result.packageSyms = initStrTable()
   result.deps = initIntSet()
   result.importDeps = initTable[FileIndex, seq[FileIndex]]()
   result.ifaces = @[]
   result.importStack = @[]
   result.inclToMod = initTable[FileIndex, FileIndex]()
   result.owners = @[]
-  result.suggestSymbols = initTable[FileIndex, seq[SymInfoPair]]()
+  result.suggestSymbols = initTable[FileIndex, SuggestFileSymbolDatabase]()
   result.suggestErrors = initTable[FileIndex, seq[Suggest]]()
   result.methods = @[]
-  initStrTable(result.compilerprocs)
-  initStrTable(result.exposed)
-  initStrTable(result.packageTypes)
+  result.compilerprocs = initStrTable()
+  result.exposed = initStrTable()
+  result.packageTypes = initStrTable()
   result.emptyNode = newNode(nkEmpty)
   result.cacheSeqs = initTable[string, PNode]()
   result.cacheCounters = initTable[string, BiggestInt]()
@@ -491,7 +585,7 @@ proc newModuleGraph*(cache: IdentCache; config: ConfigRef): ModuleGraph =
   initModuleGraphFields(result)
 
 proc resetAllModules*(g: ModuleGraph) =
-  initStrTable(g.packageSyms)
+  g.packageSyms = initStrTable()
   g.deps = initIntSet()
   g.ifaces = @[]
   g.importStack = @[]
@@ -499,11 +593,12 @@ proc resetAllModules*(g: ModuleGraph) =
   g.usageSym = nil
   g.owners = @[]
   g.methods = @[]
-  initStrTable(g.compilerprocs)
-  initStrTable(g.exposed)
+  g.compilerprocs = initStrTable()
+  g.exposed = initStrTable()
   initModuleGraphFields(g)
 
 proc getModule*(g: ModuleGraph; fileIdx: FileIndex): PSym =
+  result = nil
   if fileIdx.int32 >= 0:
     if isCachedModule(g, fileIdx.int32):
       result = g.packed[fileIdx.int32].module
@@ -609,6 +704,7 @@ proc markClientsDirty*(g: ModuleGraph; fileIdx: FileIndex) =
 
 proc needsCompilation*(g: ModuleGraph): bool =
   # every module that *depends* on this file is also dirty:
+  result = false
   for i in 0i32..<g.ifaces.len.int32:
     let m = g.ifaces[i].module
     if m != nil:
@@ -616,6 +712,7 @@ proc needsCompilation*(g: ModuleGraph): bool =
         return true
 
 proc needsCompilation*(g: ModuleGraph, fileIdx: FileIndex): bool =
+  result = false
   let module = g.getModule(fileIdx)
   if module != nil and g.isDirty(module):
     return true
@@ -637,12 +734,12 @@ proc moduleFromRodFile*(g: ModuleGraph; fileIdx: FileIndex;
   ## Returns 'nil' if the module needs to be recompiled.
   if g.config.symbolFiles in {readOnlySf, v2Sf, stressTest}:
     result = moduleFromRodFile(g.packed, g.config, g.cache, fileIdx, cachedModules)
+  else:
+    result = nil
 
 proc configComplete*(g: ModuleGraph) =
   rememberStartupConfig(g.startupPackedConfig, g.config)
 
-from std/strutils import repeat, `%`
-
 proc onProcessing*(graph: ModuleGraph, fileIdx: FileIndex, moduleStatus: string, fromModule: PSym, ) =
   let conf = graph.config
   let isNimscript = conf.isDefined("nimscript")
@@ -668,16 +765,14 @@ func belongsToStdlib*(graph: ModuleGraph, sym: PSym): bool =
   ## Check if symbol belongs to the 'stdlib' package.
   sym.getPackageSymbol.getPackageId == graph.systemModule.getPackageId
 
-proc `==`*(a, b: SymInfoPair): bool =
-  result = a.sym == b.sym and a.info.exactEquals(b.info)
-
-proc fileSymbols*(graph: ModuleGraph, fileIdx: FileIndex): seq[SymInfoPair] =
-  result = graph.suggestSymbols.getOrDefault(fileIdx, @[])
+proc fileSymbols*(graph: ModuleGraph, fileIdx: FileIndex): SuggestFileSymbolDatabase =
+  result = graph.suggestSymbols.getOrDefault(fileIdx, newSuggestFileSymbolDatabase(fileIdx, optIdeExceptionInlayHints in graph.config.globalOptions))
+  doAssert(result.fileIndex == fileIdx)
 
 iterator suggestSymbolsIter*(g: ModuleGraph): SymInfoPair =
   for xs in g.suggestSymbols.values:
-    for x in xs:
-      yield x
+    for i in xs.lineInfo.low..xs.lineInfo.high:
+      yield xs.getSymInfoPair(i)
 
 iterator suggestErrorsIter*(g: ModuleGraph): Suggest =
   for xs in g.suggestErrors.values:

compiler/modulepaths.nim

@@ -7,9 +7,11 @@
 #    distribution, for details about the copyright.
 #
 
-import ast, renderer, strutils, msgs, options, idents, os, lineinfos,
+import ast, renderer, msgs, options, idents, lineinfos,
   pathutils
 
+import std/[strutils, os]
+
 proc getModuleName*(conf: ConfigRef; n: PNode): string =
   # This returns a short relative module name without the nim extension
   # e.g. like "system", "importer" or "somepath/module"

compiler/modules.nim

@@ -25,7 +25,7 @@ template getModuleIdent(graph: ModuleGraph, filename: AbsoluteFile): PIdent =
 
 proc partialInitModule*(result: PSym; graph: ModuleGraph; fileIdx: FileIndex; filename: AbsoluteFile) =
   let packSym = getPackage(graph, fileIdx)
-  result.owner = packSym
+  setOwner(result, packSym)
   result.position = int fileIdx
 
 proc newModule*(graph: ModuleGraph; fileIdx: FileIndex): PSym =

compiler/msgs.nim

@@ -61,14 +61,12 @@ proc makeCString*(s: string): Rope =
   result.add('\"')
 
 proc newFileInfo(fullPath: AbsoluteFile, projPath: RelativeFile): TFileInfo =
-  result.fullPath = fullPath
-  #shallow(result.fullPath)
-  result.projPath = projPath
-  #shallow(result.projPath)
-  result.shortName = fullPath.extractFilename
+  result = TFileInfo(fullPath: fullPath, projPath: projPath,
+                    shortName: fullPath.extractFilename,
+                    quotedFullName: fullPath.string.makeCString,
+                    lines: @[]
+  )
   result.quotedName = result.shortName.makeCString
-  result.quotedFullName = fullPath.string.makeCString
-  result.lines = @[]
   when defined(nimpretty):
     if not result.fullPath.isEmpty:
       try:
@@ -125,18 +123,18 @@ proc fileInfoIdx*(conf: ConfigRef; filename: AbsoluteFile; isKnownFile: var bool
     conf.m.filenameToIndexTbl[canon2] = result
 
 proc fileInfoIdx*(conf: ConfigRef; filename: AbsoluteFile): FileIndex =
-  var dummy: bool
+  var dummy: bool = false
   result = fileInfoIdx(conf, filename, dummy)
 
 proc fileInfoIdx*(conf: ConfigRef; filename: RelativeFile; isKnownFile: var bool): FileIndex =
   fileInfoIdx(conf, AbsoluteFile expandFilename(filename.string), isKnownFile)
 
 proc fileInfoIdx*(conf: ConfigRef; filename: RelativeFile): FileIndex =
-  var dummy: bool
+  var dummy: bool = false
   fileInfoIdx(conf, AbsoluteFile expandFilename(filename.string), dummy)
 
 proc newLineInfo*(fileInfoIdx: FileIndex, line, col: int): TLineInfo =
-  result.fileIndex = fileInfoIdx
+  result = TLineInfo(fileIndex: fileInfoIdx)
   if line < int high(uint16):
     result.line = uint16(line)
   else:
@@ -294,9 +292,11 @@ proc toColumn*(info: TLineInfo): int {.inline.} =
   result = info.col
 
 proc toFileLineCol(info: InstantiationInfo): string {.inline.} =
+  result = ""
   result.toLocation(info.filename, info.line, info.column + ColOffset)
 
 proc toFileLineCol*(conf: ConfigRef; info: TLineInfo): string {.inline.} =
+  result = ""
   result.toLocation(toMsgFilename(conf, info), info.line.int, info.col.int + ColOffset)
 
 proc `$`*(conf: ConfigRef; info: TLineInfo): string = toFileLineCol(conf, info)
@@ -408,7 +408,7 @@ proc getMessageStr(msg: TMsgKind, arg: string): string = msgKindToString(msg) %
 type TErrorHandling* = enum doNothing, doAbort, doRaise
 
 proc log*(s: string) =
-  var f: File
+  var f: File = default(File)
   if open(f, getHomeDir() / "nimsuggest.log", fmAppend):
     f.writeLine(s)
     close(f)
@@ -507,6 +507,8 @@ proc getSurroundingSrc(conf: ConfigRef; info: TLineInfo): string =
     result = "\n" & indent & $sourceLine(conf, info)
     if info.col >= 0:
       result.add "\n" & indent & spaces(info.col) & '^'
+  else:
+    result = ""
 
 proc formatMsg*(conf: ConfigRef; info: TLineInfo, msg: TMsgKind, arg: string): string =
   let title = case msg
@@ -627,7 +629,7 @@ proc warningDeprecated*(conf: ConfigRef, info: TLineInfo = gCmdLineInfo, msg = "
   message(conf, info, warnDeprecated, msg)
 
 proc internalErrorImpl(conf: ConfigRef; info: TLineInfo, errMsg: string, info2: InstantiationInfo) =
-  if conf.cmd == cmdIdeTools and conf.structuredErrorHook.isNil: return
+  if conf.cmd in {cmdIdeTools, cmdCheck} and conf.structuredErrorHook.isNil: return
   writeContext(conf, info)
   liMessage(conf, info, errInternal, errMsg, doAbort, info2)
 
@@ -667,31 +669,6 @@ template listMsg(title, r) =
 proc listWarnings*(conf: ConfigRef) = listMsg("Warnings:", warnMin..warnMax)
 proc listHints*(conf: ConfigRef) = listMsg("Hints:", hintMin..hintMax)
 
-proc uniqueModuleName*(conf: ConfigRef; fid: FileIndex): string =
-  ## The unique module name is guaranteed to only contain {'A'..'Z', 'a'..'z', '0'..'9', '_'}
-  ## so that it is useful as a C identifier snippet.
-  let path = AbsoluteFile toFullPath(conf, fid)
-  let rel =
-    if path.string.startsWith(conf.libpath.string):
-      relativeTo(path, conf.libpath).string
-    else:
-      relativeTo(path, conf.projectPath).string
-  let trunc = if rel.endsWith(".nim"): rel.len - len(".nim") else: rel.len
-  result = newStringOfCap(trunc)
-  for i in 0..<trunc:
-    let c = rel[i]
-    case c
-    of 'a'..'z':
-      result.add c
-    of {os.DirSep, os.AltSep}:
-      result.add 'Z' # because it looks a bit like '/'
-    of '.':
-      result.add 'O' # a circle
-    else:
-      # We mangle upper letters and digits too so that there cannot
-      # be clashes with our special meanings of 'Z' and 'O'
-      result.addInt ord(c)
-
 proc genSuccessX*(conf: ConfigRef) =
   let mem =
     when declared(system.getMaxMem): formatSize(getMaxMem()) & " peakmem"
@@ -730,6 +707,8 @@ proc genSuccessX*(conf: ConfigRef) =
   elif conf.outFile.isEmpty and conf.cmd notin {cmdJsonscript} + cmdDocLike + cmdBackends:
     # for some cmd we expect a valid absOutFile
     output = "unknownOutput"
+  elif optStdout in conf.globalOptions:
+    output = "stdout"
   else:
     output = $conf.absOutFile
   if conf.filenameOption != foAbs: output = output.AbsoluteFile.extractFilename

compiler/ndi.nim

@@ -29,7 +29,7 @@ proc doWrite(f: var NdiFile; s: PSym; conf: ConfigRef) =
   f.buf.add "\t"
   f.buf.addInt s.info.col.int
   f.f.write(s.name.s, "\t")
-  f.f.writeRope(s.loc.r)
+  f.f.writeRope(s.loc.snippet)
   f.f.writeLine("\t", toFullPath(conf, s.info), "\t", f.buf)
 
 template writeMangledName*(f: NdiFile; s: PSym; conf: ConfigRef) =

compiler/nilcheck.nim

@@ -7,8 +7,8 @@
 #    distribution, for details about the copyright.
 #
 
-import ast, renderer, intsets, tables, msgs, options, lineinfos, strformat, idents, treetab, hashes
-import sequtils, strutils, sets
+import ast, renderer, msgs, options, lineinfos, idents, treetab
+import std/[intsets, tables, sequtils, strutils, sets, strformat, hashes]
 
 when defined(nimPreviewSlimSystem):
   import std/assertions
@@ -309,6 +309,7 @@ proc symbol(n: PNode): Symbol =
   # echo "symbol ", n, " ", n.kind, " ", result.int
 
 func `$`(map: NilMap): string =
+  result = ""
   var now = map
   var stack: seq[NilMap] = @[]
   while not now.isNil:
@@ -416,7 +417,7 @@ proc moveOut(ctx: NilCheckerContext, map: NilMap, target: PNode) =
   if targetSetIndex != noSetIndex:
     var targetSet = map.sets[targetSetIndex]
     if targetSet.len > 1:
-      var other: ExprIndex
+      var other: ExprIndex = default(ExprIndex)
 
       for element in targetSet:
         if element.ExprIndex != targetIndex:
@@ -497,7 +498,7 @@ proc checkCall(n, ctx, map): Check =
   # check args and handle possible mutations
 
   var isNew = false
-  result.map = map
+  result = Check(map: map)
   for i, child in n:
     discard check(child, ctx, map)
 
@@ -506,7 +507,7 @@ proc checkCall(n, ctx, map): Check =
       # as it might have been mutated
       # TODO similar for normal refs and fields: find dependent exprs: brackets
 
-      if child.kind == nkHiddenAddr and not child.typ.isNil and child.typ.kind == tyVar and child.typ[0].kind == tyRef:
+      if child.kind == nkHiddenAddr and not child.typ.isNil and child.typ.kind == tyVar and child.typ.elementType.kind == tyRef:
         if not isNew:
           result.map = newNilMap(map)
           isNew = true
@@ -561,7 +562,7 @@ proc derefWarning(n, ctx, map; kind: Nilability) =
   if n.info in ctx.warningLocations:
     return
   ctx.warningLocations.incl(n.info)
-  var a: seq[History]
+  var a: seq[History] = @[]
   if n.kind == nkSym:
     a = history(map, ctx.index(n))
   var res = ""
@@ -752,6 +753,7 @@ proc checkReturn(n, ctx, map): Check =
 
 proc checkIf(n, ctx, map): Check =
   ## check branches based on condition
+  result = default(Check)
   var mapIf: NilMap = map
 
   # first visit the condition
@@ -765,7 +767,7 @@ proc checkIf(n, ctx, map): Check =
   # the state of the conditions: negating conditions before the current one
   var layerHistory = newNilMap(mapIf)
   # the state after branch effects
-  var afterLayer: NilMap
+  var afterLayer: NilMap = nil
   # the result nilability for expressions
   var nilability = Safe
 
@@ -824,7 +826,7 @@ proc checkFor(n, ctx, map): Check =
   var check2 = check(n.sons[2], ctx, m)
   var map2 = check2.map
 
-  result.map = ctx.union(map0, m)
+  result = Check(map: ctx.union(map0, m))
   result.map = ctx.union(result.map, map2)
   result.nilability = Safe
 
@@ -852,7 +854,7 @@ proc checkWhile(n, ctx, map): Check =
   var check2 = check(n.sons[1], ctx, m)
   var map2 = check2.map
 
-  result.map = ctx.union(map0, map1)
+  result = Check(map: ctx.union(map0, map1))
   result.map = ctx.union(result.map, map2)
   result.nilability = Safe
 
@@ -862,9 +864,10 @@ proc checkInfix(n, ctx, map): Check =
   ##   a or b : map is an union of a and b's
   ##   a == b : use checkCondition
   ##   else: no change, just check args
+  result = default(Check)
   if n[0].kind == nkSym:
-    var mapL: NilMap
-    var mapR: NilMap
+    var mapL: NilMap = nil
+    var mapR: NilMap = nil
     if n[0].sym.magic notin {mAnd, mEqRef}:
       mapL = checkCondition(n[1], ctx, map, false, false)
       mapR = checkCondition(n[2], ctx, map, false, false)
@@ -897,7 +900,7 @@ proc checkInfix(n, ctx, map): Check =
 proc checkIsNil(n, ctx, map; isElse: bool = false): Check =
   ## check isNil calls
   ## update the map depending on if it is not isNil or isNil
-  result.map = newNilMap(map)
+  result = Check(map: newNilMap(map))
   let value = n[1]
   result.map.store(ctx, ctx.index(n[1]), if not isElse: Nil else: Safe, TArg, n.info, n)
 
@@ -916,7 +919,7 @@ proc infix(ctx: NilCheckerContext, l: PNode, r: PNode, magic: TMagic): PNode =
     newSymNode(op, r.info),
     l,
     r)
-  result.typ = newType(tyBool, nextTypeId ctx.idgen, nil)
+  result.typ() = newType(tyBool, ctx.idgen, nil)
 
 proc prefixNot(ctx: NilCheckerContext, node: PNode): PNode =
   var cache = newIdentCache()
@@ -926,7 +929,7 @@ proc prefixNot(ctx: NilCheckerContext, node: PNode): PNode =
   result = nkPrefix.newTree(
     newSymNode(op, node.info),
     node)
-  result.typ = newType(tyBool, nextTypeId ctx.idgen, nil)
+  result.typ() = newType(tyBool, ctx.idgen, nil)
 
 proc infixEq(ctx: NilCheckerContext, l: PNode, r: PNode): PNode =
   infix(ctx, l, r, mEqRef)
@@ -945,9 +948,9 @@ proc checkCase(n, ctx, map): Check =
   #   c2
   # also a == true is a , a == false is not a
   let base = n[0]
-  result.map = map.copyMap()
+  result = Check(map: map.copyMap())
   result.nilability = Safe
-  var a: PNode
+  var a: PNode = nil
   for child in n:
     case child.kind:
     of nkOfBranch:
@@ -1217,12 +1220,12 @@ proc check(n: PNode, ctx: NilCheckerContext, map: NilMap): Check =
     result = check(n.sons[1], ctx, map)
   of nkStmtList, nkStmtListExpr, nkChckRangeF, nkChckRange64, nkChckRange,
      nkBracket, nkCurly, nkPar, nkTupleConstr, nkClosure, nkObjConstr, nkElse:
-    result.map = map
+    result = Check(map: map)
     if n.kind in {nkObjConstr, nkTupleConstr}:
       # TODO deeper nested elements?
       # A(field: B()) #
       # field: Safe ->
-      var elements: seq[(PNode, Nilability)]
+      var elements: seq[(PNode, Nilability)] = @[]
       for i, child in n:
         result = check(child, ctx, result.map)
         if i > 0:
@@ -1244,10 +1247,10 @@ proc check(n: PNode, ctx: NilCheckerContext, map: NilMap): Check =
     result = checkIf(n, ctx, map)
   of nkAsgn, nkFastAsgn, nkSinkAsgn:
     result = checkAsgn(n[0], n[1], ctx, map)
-  of nkVarSection:
-    result.map = map
+  of nkVarSection, nkLetSection:
+    result = Check(map: map)
     for child in n:
-      result = checkAsgn(child[0], child[2], ctx, result.map)
+      result = checkAsgn(child[0].skipPragmaExpr, child[2], ctx, result.map)
   of nkForStmt:
     result = checkFor(n, ctx, map)
   of nkCaseStmt:
@@ -1271,8 +1274,7 @@ proc check(n: PNode, ctx: NilCheckerContext, map: NilMap): Check =
   else:
 
     var elementMap = map.copyMap()
-    var elementCheck: Check
-    elementCheck.map = elementMap
+    var elementCheck = Check(map: elementMap)
     for element in n:
       elementCheck = check(element, ctx, elementCheck.map)
 
@@ -1333,7 +1335,7 @@ proc preVisit(ctx: NilCheckerContext, s: PSym, body: PNode, conf: ConfigRef) =
   ctx.symbolIndices = {resultId: resultExprIndex}.toTable()
   var cache = newIdentCache()
   ctx.expressions = SeqOfDistinct[ExprIndex, PNode](@[newIdentNode(cache.getIdent("result"), s.ast.info)])
-  var emptySet: IntSet # set[ExprIndex]
+  var emptySet: IntSet = initIntSet() # set[ExprIndex]
   ctx.dependants = SeqOfDistinct[ExprIndex, IntSet](@[emptySet])
   for i, arg in s.typ.n.sons:
     if i > 0:
@@ -1365,7 +1367,7 @@ proc checkNil*(s: PSym; body: PNode; conf: ConfigRef, idgen: IdGenerator) =
         continue
       map.store(context, context.index(child), typeNilability(child.typ), TArg, child.info, child)
 
-  map.store(context, resultExprIndex, if not s.typ[0].isNil and s.typ[0].kind == tyRef: Nil else: Safe, TResult, s.ast.info)
+  map.store(context, resultExprIndex, if not s.typ.returnType.isNil and s.typ.returnType.kind == tyRef: Nil else: Safe, TResult, s.ast.info)
 
   # echo "checking ", s.name.s, " ", filename
 
@@ -1381,5 +1383,5 @@ proc checkNil*(s: PSym; body: PNode; conf: ConfigRef, idgen: IdGenerator) =
   # (ANotNil, BNotNil) :
   # do we check on asgn nilability at all?
 
-  if not s.typ[0].isNil and s.typ[0].kind == tyRef and tfNotNil in s.typ[0].flags:
+  if not s.typ.returnType.isNil and s.typ.returnType.kind == tyRef and tfNotNil in s.typ.returnType.flags:
     checkResult(s.ast, context, res.map)

compiler/nim.cfg

@@ -4,11 +4,11 @@ hint[XDeclaredButNotUsed]:off
 
 define:booting
 define:nimcore
-define:nimPreviewFloatRoundtrip
 define:nimPreviewSlimSystem
 define:nimPreviewCstringConversion
 define:nimPreviewProcConversion
 define:nimPreviewRangeDefault
+define:nimPreviewNonVarDestructor
 threads:off
 
 #import:"$projectpath/testability"
@@ -41,5 +41,22 @@ define:useStdoutAsStdmsg
 @end
 
 @if nimHasWarnBareExcept:
+  warning[BareExcept]:on
   warningAserror[BareExcept]:on
 @end
+
+
+@if nimUseStrictDefs:
+  experimental:strictDefs
+  warningAsError[Uninit]:on
+  warningAsError[ProveInit]:on
+@end
+
+@if nimHasWarnStdPrefix:
+  warning[StdPrefix]:on
+  warningAsError[StdPrefix]:on
+@end
+
+@if nimHasVtables:
+  experimental:vtables
+@end

compiler/nim.nim

@@ -28,7 +28,7 @@ import
   commands, options, msgs, extccomp, main, idents, lineinfos, cmdlinehelper,
   pathutils, modulegraphs
 
-from browsers import openDefaultBrowser
+from std/browsers import openDefaultBrowser
 from nodejs import findNodeJs
 
 when hasTinyCBackend:
@@ -91,6 +91,9 @@ proc getNimRunExe(conf: ConfigRef): string =
   if conf.isDefined("mingw"):
     if conf.isDefined("i386"): result = "wine"
     elif conf.isDefined("amd64"): result = "wine64"
+    else: result = ""
+  else:
+    result = ""
 
 proc handleCmdLine(cache: IdentCache; conf: ConfigRef) =
   let self = NimProg(
@@ -113,7 +116,9 @@ proc handleCmdLine(cache: IdentCache; conf: ConfigRef) =
     conf.backend = backendC
 
   if conf.selectedGC == gcUnselected:
-    if conf.backend in {backendC, backendCpp, backendObjc}:
+    if conf.backend in {backendC, backendCpp, backendObjc} or
+        (conf.cmd in cmdDocLike and conf.backend != backendJs) or
+        conf.cmd == cmdGendepend:
       initOrcDefines(conf)
 
   mainCommand(graph)
@@ -137,7 +142,7 @@ proc handleCmdLine(cache: IdentCache; conf: ConfigRef) =
         # tasyncjs_fail` would fail, refs https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode
         if cmdPrefix.len == 0: cmdPrefix = findNodeJs().quoteShell
         cmdPrefix.add " --unhandled-rejections=strict"
-      else: doAssert false, $conf.backend
+      else: raiseAssert $conf.backend
       if cmdPrefix.len > 0: cmdPrefix.add " "
         # without the `cmdPrefix.len > 0` check, on windows you'd get a cryptic:
         # `The parameter is incorrect`

compiler/nimblecmd.nim

@@ -9,8 +9,9 @@
 
 ## Implements some helper procs for Nimble (Nim's package manager) support.
 
-import parseutils, strutils, os, options, msgs, sequtils, lineinfos, pathutils,
-  tables
+import options, msgs, lineinfos, pathutils
+
+import std/[parseutils, strutils, os, tables, sequtils]
 
 when defined(nimPreviewSlimSystem):
   import std/[syncio, assertions]
@@ -37,11 +38,16 @@ proc isSpecial(ver: Version): bool =
 
 proc isValidVersion(v: string): bool =
   if v.len > 0:
-    if v[0] in {'#'} + Digits: return true
+    if v[0] in {'#'} + Digits:
+      result = true
+    else:
+      result = false
+  else:
+    result = false
 
 proc `<`*(ver: Version, ver2: Version): bool =
   ## This is synced from Nimble's version module.
-
+  result = false
   # Handling for special versions such as "#head" or "#branch".
   if ver.isSpecial or ver2.isSpecial:
     if ver2.isSpecial and ($ver2).normalize == "#head":
@@ -73,6 +79,8 @@ proc getPathVersionChecksum*(p: string): tuple[name, version, checksum: string]
   ## ``/home/user/.nimble/pkgs/package-0.1-febadeaea2345e777f0f6f8433f7f0a52edd5d1b`` into
   ## ``("/home/user/.nimble/pkgs/package", "0.1", "febadeaea2345e777f0f6f8433f7f0a52edd5d1b")``
 
+  result = ("", "", "")
+
   const checksumSeparator = '-'
   const versionSeparator = '-'
   const specialVersionSepartator = "-#"
@@ -145,7 +153,7 @@ proc addNimblePath(conf: ConfigRef; p: string, info: TLineInfo) =
     conf.lazyPaths.insert(AbsoluteDir path, 0)
 
 proc addPathRec(conf: ConfigRef; dir: string, info: TLineInfo) =
-  var packages: PackageInfo
+  var packages: PackageInfo = initTable[string, tuple[version, checksum: string]]()
   var pos = dir.len-1
   if dir[pos] in {DirSep, AltSep}: inc(pos)
   for k,p in os.walkDir(dir):