merge upstream code

Merge remote-tracking branch 'upstream/araq-nir' into pr_ast2ir
NIR: implemented builtin
2026-08-31 10:53:40 +00:00 · 2023-10-04 15:07:11 +08:00 · 2023-10-04 15:03:36 +08:00 · 2023-10-03 23:57:38 +02:00 · 2023-10-03 22:27:19 +08:00 · 2023-10-03 09:08:20 +02:00
1337 changed files with 24566 additions and 58488 deletions
--- a/.github/ISSUE_TEMPLATE/bug_report.yml
+++ b/.github/ISSUE_TEMPLATE/bug_report.yml
@@ -7,26 +7,25 @@ body:
 - type: markdown
  attributes:
    value: |
-      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: nim-version
-  attributes:
-    label: Nim Version
-    description: |
-      Can be obtained from `nim -v` on the command line along with the OS/architecture.
-      For development versions, including the commit hash may help.
-  validations:
-    required: true
+      - **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.

 - type: textarea
  id: description
  attributes:
    label: Description
    description: |
-      Describe the problem. Code example can be given here.
-    placeholder: Bug reports with reproducible code or detailed information will be fixed faster.
+      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.
+  validations:
+    required: true
+    
+- type: textarea
+  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.
  validations:
    required: true

@@ -35,7 +34,7 @@ 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 or detailed information will be fixed faster.
+    placeholder: Bug reports with reproducible code and detailed information will be fixed faster.
    render: text

 - type: textarea
@@ -43,14 +42,14 @@ 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 or detailed information will be fixed faster.
+    placeholder: Bug reports with reproducible code and detailed information will be fixed faster.
    render: text

 - type: textarea
-  id: known-workarounds
+  id: possible-solution
  attributes:
-    label: Known Workarounds
-    description: Provide any known workarounds.
+    label: Possible Solution
+    description: Propose a possible solution.
  validations:
    required: false

@@ -65,9 +64,13 @@ body:
 - type: markdown
  attributes:
    value: |
-      - 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).
+      - 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).
      - 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 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).
+      - 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 (e.g. `choosenim 2.0.0`). The Nim repo also supports online bisecting
+        via making a comment, which contains a code block starting by `!nim c`, `!nim js` etc. , see [nimrun-action](https://github.com/juancarlospaco/nimrun-action).
      - [Please, consider a Donation for the Nim project.](https://nim-lang.org/donate.html)
--- a/.github/workflows/bisects.yml
+++ b/.github/workflows/bisects.yml
@@ -5,34 +5,19 @@ on:
    types: created

 jobs:
-  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 }}
+  test:
+    runs-on: ubuntu-latest
    steps:
-      - uses: actions/checkout@v5
+    - uses: actions/checkout@v4

-      - name: Install OpenSSL (Windows)
-        if: |
-          runner.os == 'Windows'
-        run: choco install openssl.light --version=1.1.1.0  # OpenSSL 3.x removed SSL_library_init
-        shell: 'powershell'
+    # nimrun-action requires Nim installed.
+    - uses: jiro4989/setup-nim-action@v1
+      with:
+        nim-version: 'devel'

-      # v2 wont work here, because uses "hardcoded" nim versions, action "dynamically" finds version with bug.
-      - 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
-        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 }}
+    - uses: juancarlospaco/nimrun-action@nim
+      with:
+        github-token: ${{ secrets.GITHUB_TOKEN }}
--- a/.github/workflows/ci_bench.yml
+++ b/.github/workflows/ci_bench.yml
@@ -0,0 +1,115 @@
+name: Benchmarks CI
+on:
+  pull_request:
+  push:
+    branches:
+      - 'devel'
+
+jobs:
+  build:
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-20.04]
+        cpu: [amd64]
+    name: '${{ matrix.os }}'
+    runs-on: ${{ matrix.os }}
+    timeout-minutes: 60 # refs bug #18178
+    steps:
+      - name: 'Checkout'
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 2
+
+      - name: 'Install node.js 16.x'
+        uses: actions/setup-node@v3
+        with:
+          node-version: '16.x'
+
+      - name: 'Install dependencies (Linux amd64)'
+        if: runner.os == 'Linux' && matrix.cpu == 'amd64'
+        run: |
+          sudo apt-fast update -qq
+          DEBIAN_FRONTEND='noninteractive' \
+            sudo apt-fast install --no-install-recommends -yq \
+              libcurl4-openssl-dev libgc-dev libsdl1.2-dev libsfml-dev \
+              valgrind libc6-dbg libblas-dev xorg-dev
+
+      - name: 'Add build binaries to PATH'
+        shell: bash
+        run: echo "${{ 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@v4
+        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
--- a/.github/workflows/ci_docs.yml
+++ b/.github/workflows/ci_docs.yml
@@ -41,11 +41,11 @@ jobs:
        target: [linux, windows, osx]
        include:
          - target: linux
-            os: ubuntu-22.04
+            os: ubuntu-20.04
          - target: windows
-            os: windows-latest
+            os: windows-2019
          - target: osx
-            os: macos-15
+            os: macos-11

    name: ${{ matrix.target }}
    runs-on: ${{ matrix.os }}
@@ -109,7 +109,7 @@ jobs:
        if: |
          github.event_name == 'push' && github.ref == 'refs/heads/devel' &&
          matrix.target == 'linux'
-        uses: crazy-max/ghaction-github-pages@v4
+        uses: crazy-max/ghaction-github-pages@v3
        with:
          build_dir: doc/html
        env:
--- a/.github/workflows/ci_packages.yml
+++ b/.github/workflows/ci_packages.yml
@@ -4,7 +4,6 @@ on:
  push:
    branches:
      - 'devel'
-      - 'version-2-2'
      - 'version-2-0'
      - 'version-1-6'
      - 'version-1-2'
@@ -18,13 +17,9 @@ jobs:
    strategy:
      fail-fast: false
      matrix:
-        os: [ubuntu-latest, macos-14]
+        os: [ubuntu-20.04, macos-11]
+        cpu: [amd64]
        batch: ["allowed_failures", "0_3", "1_3", "2_3"] # list of `index_num`
-        include:
-          - os: ubuntu-latest
-            cpu: amd64
-          - os: macos-14
-            cpu: arm64
    name: '${{ matrix.os }} (batch: ${{ matrix.batch }})'
    runs-on: ${{ matrix.os }}
    timeout-minutes: 60 # refs bug #18178
@@ -37,23 +32,22 @@ jobs:
        with:
          fetch-depth: 2

-      - name: 'Install node.js 20.x'
-        uses: actions/setup-node@v4
+      - name: 'Install node.js 16.x'
+        uses: actions/setup-node@v3
        with:
-          node-version: '20.x'
+          node-version: '16.x'

      - name: 'Install dependencies (Linux amd64)'
        if: runner.os == 'Linux' && matrix.cpu == 'amd64'
        run: |
-          sudo apt-get update -qq
+          sudo apt-fast update -qq
          DEBIAN_FRONTEND='noninteractive' \
-            sudo apt-get install --no-install-recommends -yq \
+            sudo apt-fast install --no-install-recommends -yq \
              libcurl4-openssl-dev libgc-dev libsdl1.2-dev libsfml-dev \
-              valgrind libc6-dbg libblas-dev liblapack-dev libpcre3 xorg-dev
+              valgrind libc6-dbg libblas-dev xorg-dev
      - 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
--- a/.github/workflows/ci_publish.yml
+++ b/.github/workflows/ci_publish.yml
@@ -11,7 +11,7 @@ jobs:
    strategy:
      fail-fast: false
      matrix:
-        os: [ubuntu-22.04]
+        os: [ubuntu-20.04]
        cpu: [amd64]
    name: '${{ matrix.os }}'
    runs-on: ${{ matrix.os }}
@@ -21,10 +21,10 @@ jobs:
        with:
          fetch-depth: 2

-      - name: 'Install node.js'
-        uses: actions/setup-node@v4
+      - name: 'Install node.js 16.x'
+        uses: actions/setup-node@v3
        with:
-          node-version: ''
+          node-version: '16.x'

      - name: 'Install dependencies (Linux amd64)'
        if: runner.os == 'Linux' && matrix.cpu == 'amd64'
@@ -34,6 +34,17 @@ jobs:
            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: '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
@@ -60,7 +71,7 @@ jobs:
        run: nim c -r -d:release ci/action.nim

      - name: 'Comment'
-        uses: actions/github-script@v7
+        uses: actions/github-script@v6
        with:
          script: |
            const fs = require('fs');
--- a/.github/workflows/stale.yml
+++ b/.github/workflows/stale.yml
@@ -9,7 +9,7 @@ jobs:
  stale:
    runs-on: ubuntu-latest
    steps:
-      - uses: actions/stale@v9
+      - uses: actions/stale@v8
        with:
          days-before-pr-stale:    365
          days-before-pr-close:    30
--- a/.gitignore
+++ b/.gitignore
@@ -68,7 +68,6 @@ testament.db
 /csources
 /csources_v1
 /csources_v2
-/csources_v3

 /dist/
 # /lib/fusion # fusion is now unbundled; `git status` should reveal if it's there so users can act on it
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -20,7 +20,7 @@ jobs:
  strategy:
    matrix:
      Linux_amd64:
-        vmImage: 'ubuntu-24.04'
+        vmImage: 'ubuntu-20.04'
        CPU: amd64
      # regularly breaks, refs bug #17325
 #       Linux_i386:
@@ -28,24 +28,24 @@ jobs:
 #         # g++-multilib : Depends: gcc-multilib (>= 4:5.3.1-1ubuntu1) but it is not going to be installed
 #         vmImage: 'ubuntu-18.04'
 #         CPU: i386
-      OSX_arm64:
-        vmImage: 'macos-15'
-        CPU: arm64
-      OSX_arm64_cpp:
-        vmImage: 'macos-15'
-        CPU: arm64
+      OSX_amd64:
+        vmImage: 'macOS-11'
+        CPU: amd64
+      OSX_amd64_cpp:
+        vmImage: 'macOS-11'
+        CPU: amd64
        NIM_COMPILE_TO_CPP: true
      Windows_amd64_batch0_3:
-        vmImage: 'windows-2025'
+        vmImage: 'windows-2019'
        CPU: amd64
        # see also: `NIM_TEST_PACKAGES`
        NIM_TESTAMENT_BATCH: "0_3"
      Windows_amd64_batch1_3:
-        vmImage: 'windows-2025'
+        vmImage: 'windows-2019'
        CPU: amd64
        NIM_TESTAMENT_BATCH: "1_3"
      Windows_amd64_batch2_3:
-        vmImage: 'windows-2025'
+        vmImage: 'windows-2019'
        CPU: amd64
        NIM_TESTAMENT_BATCH: "2_3"

@@ -73,19 +73,17 @@ jobs:

    - task: NodeTool@0
      inputs:
-        versionSpec: '20.x'
-      displayName: 'Install node.js 20.x'
+        versionSpec: '16.x'
+      displayName: 'Install node.js 16.x'
      condition: and(succeeded(), eq(variables['skipci'], 'false'))

    - bash: |
        set -e
        . ci/funs.sh
-        echo_run sudo add-apt-repository universe
-        echo_run sudo apt-get update -qq
+        echo_run sudo apt-fast update -qq
        DEBIAN_FRONTEND='noninteractive' \
-          echo_run sudo apt-get install --no-install-recommends -yq \
-            gcc-14 g++-14 libpcre3 liblapack-dev libpcre3 liblapack-dev libcurl4-openssl-dev libgc-dev libsdl1.2-dev libsfml-dev valgrind libc6-dbg
-        echo_run sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-14 60 --slave /usr/bin/g++ g++ /usr/bin/g++-14
+          echo_run sudo apt-fast install --no-install-recommends -yq \
+            libcurl4-openssl-dev libgc-dev libsdl1.2-dev libsfml-dev valgrind libc6-dbg
      displayName: 'Install dependencies (amd64 Linux)'
      condition: and(succeeded(), eq(variables['skipci'], 'false'), eq(variables['Agent.OS'], 'Linux'), eq(variables['CPU'], 'amd64'))

@@ -102,16 +100,15 @@ jobs:
        Pin-Priority: 1001
        EOF

-        # echo_run sudo apt-get update -qq
-        echo_run sudo apt-get update -qq || echo "failed, see bug #17343"
+        # echo_run sudo apt-fast update -qq
+        echo_run sudo apt-fast update -qq || echo "failed, see bug #17343"
        # `:i386` (e.g. in `libffi-dev:i386`) is needed otherwise you may get:
        # `could not load: libffi.so` during dynamic loading.
        DEBIAN_FRONTEND='noninteractive' \
-          echo_run sudo apt-get install --no-install-recommends --allow-downgrades -yq \
+          echo_run sudo apt-fast install --no-install-recommends --allow-downgrades -yq \
            g++-multilib gcc-multilib libcurl4-openssl-dev:i386 libgc-dev:i386 \
            libsdl1.2-dev:i386 libsfml-dev:i386 libglib2.0-dev:i386 libffi-dev:i386

-
        cat << EOF > bin/gcc
        #!/bin/bash

@@ -133,7 +130,6 @@ 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
--- a/build_all.bat
+++ b/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
--- a/changelog.md
+++ b/changelog.md
@@ -1,119 +1,33 @@
-# v2.x.x - yyyy-mm-dd
+# v2.2.0 - 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.
-
- With `-d:nimPreviewCheckedClose`, the `close` function in the `std/syncio` module now raises an IO exception in case of an error.
-
- Unknown warnings and hints now gives warnings `warnUnknownNotes` instead of
-errors.
-
- With `-d:nimPreviewAsmSemSymbol`, backticked symbols are type checked in the `asm/emit` statements.
-
- The bare `except:` now panics on `Defect`. Use `except Exception:` or `except Defect:` to catch `Defect`. `--legacy:noPanicOnExcept` is provided for a transition period.
-
- With `-d:nimPreviewCStringComparisons`, comparsions (`<`, `>`, `<=`, `>=`) between cstrings switch from reference semantics to value semantics like `==` and `!=`.
-
- `std/parsesql` has been moved to a nimble package, use `nimble` or `atlas` to install it.
-
- With `-d:nimPreviewDuplicateModuleError`, importing two modules that share the same name becomes a compile-time error. This includes importing the same module more than once. Use `import foo as foo1` (or other aliases) to avoid collisions.
-
- Adds the switch `--mangle:nim|cpp`, which selects `nim` or `cpp` style name mangling when used with `debuginfo` on, defaults to `cpp`.
-
- The second parameter of `succ`, `pred`, `inc`, and `dec` in `system` now accepts `SomeInteger` (previously `Ordinal`).
-
- Bitshift operators (`shl`, `shr`, `ashr`) now apply bitmasking to the right operand in the C/C++/VM/JS backends.

 ## Standard library additions and 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.
- `strutils.multiReplace` overload for character set replacements in a single pass.
-	Useful for string sanitation. Follows existing multiReplace semantics.
-
- `std/files` adds:
-  - Exports `CopyFlag` enum and `FilePermission` type for fine-grained control of file operations
-  - New file operation procs with `Path` support:
-    - `getFilePermissions`, `setFilePermissions` for managing permissions
-    - `tryRemoveFile` for file deletion
-    - `copyFile` with configurable buffer size and symlink handling
-    - `copyFileWithPermissions` to preserve file attributes
-    - `copyFileToDir` for copying files into directories
-
- `std/dirs` adds:
-  - New directory operation procs with `Path` support:
-    - `copyDir` with special file handling options
-    - `copyDirWithPermissions` to recursively preserve attributes
-
- `system.setLenUninit` now supports refc, JS and VM backends.
-
 [//]: # "Changes:"

- `std/math` The `^` symbol now supports floating-point as exponent in addition to the Natural type.
- `min`, `max`, and `sequtils`' `minIndex`, `maxIndex` and `minmax` for `openArray`s now accept a comparison function.
- `system.substr` implementation now uses `copymem` (wrapped C `memcpy`) for copying data, if available at compilation.
- `system.newStringUninit` is now considered free of side-effects allowing it to be used with `--experimental:strictFuncs`.
+
+[//]: # "Additions:"
+
+- Added `newStringUninit` to system, which creates a new string of length `len` like `newString` but with uninitialized content.
+- Added `hasDefaultValue` to `std/typetraits` to check if a type has a valid default value.
+
+[//]: # "Deprecations:"
+
+
+[//]: # "Removals:"
+

 ## Language changes

- An experimental option `--experimental:typeBoundOps` has been added that
-  implements the RFC https://github.com/nim-lang/RFCs/issues/380.
-  This makes the behavior of interfaces like `hash`, `$`, `==` etc. more
-  reliable for nominal types across indirect/restricted imports.

-  ```nim
-  # objs.nim
-  import std/hashes
-
-  type
-    Obj* = object
-      x*, y*: int
-      z*: string # to be ignored for equality
-
-  proc `==`*(a, b: Obj): bool =
-    a.x == b.x and a.y == b.y
-
-  proc hash*(a: Obj): Hash =
-    $!(hash(a.x) &! hash(a.y))
-  ```
-
-  ```nim
-  # main.nim
-  {.experimental: "typeBoundOps".}
-  from objs import Obj # objs.hash, objs.`==` not imported
-  import std/tables
-
-  var t: Table[Obj, int]
-  t[Obj(x: 3, y: 4, z: "debug")] = 34
-  echo t[Obj(x: 3, y: 4, z: "ignored")] # 34
-  ```
-
-  See the [experimental manual](https://nim-lang.github.io/Nim/manual_experimental.html#typeminusbound-overloads)
-  for more information.

 ## Compiler changes

- Fixed a bug where `sizeof(T)` inside a `typedesc` template called from a generic type's
-  `when` clause would error with "'sizeof' requires '.importc' types to be '.completeStruct'".
-  The issue was that `hasValuelessStatics` in `semtypinst.nim` didn't recognize
-  `tyTypeDesc(tyGenericParam)` as an unresolved generic parameter.

 ## Tool changes

- Added `--stdinfile` flag to name of the file used when running program from stdin (defaults to `stdinfile.nim`)
+- koch now allows bootstrapping with `-d:nimHasLibFFI`, replacing the older option of building the compiler directly w/ the `libffi` nimble package in tow.

-## Documentation changes
-
- Added documentation for the `completeStruct` pragma in the manual.
--- a/changelogs/changelog_0_18_1.md
+++ b/changelogs/changelog_0_18_1.md
@@ -53,7 +53,7 @@
  - [``joyent_http_parser``](https://github.com/nim-lang/joyent_http_parser)

 - Proc [toCountTable](https://nim-lang.org/docs/tables.html#toCountTable,openArray[A])
-  now produces a `CountTable` with values corresponding to the number of occurrences
+  now produces a `CountTable` with values correspoding to the number of occurrences
  of the key in the input. It used to produce a table with all values set to `1`.

  Counting occurrences in a sequence used to be:
@@ -339,7 +339,7 @@ for i in a..b:

 - Fixed "ReraiseError when using try/except within finally block"
  ([#5871](https://github.com/nim-lang/Nim/issues/5871))
- Fixed "Range type inference leads to counter-intuitive behaviour"
+- Fixed "Range type inference leads to counter-intuitive behvaiour"
  ([#5854](https://github.com/nim-lang/Nim/issues/5854))
 - Fixed "JSON % operator can fail in extern procs with dynamic types"
  ([#6385](https://github.com/nim-lang/Nim/issues/6385))
@@ -403,7 +403,7 @@ for i in a..b:
  ([#6589](https://github.com/nim-lang/Nim/issues/6589))
 - Fixed "Generated c code calls function twice"
  ([#6292](https://github.com/nim-lang/Nim/issues/6292))
- Fixed "Range type inference leads to counter-intuitive behaviour"
+- Fixed "Range type inference leads to counter-intuitive behvaiour"
  ([#5854](https://github.com/nim-lang/Nim/issues/5854))
 - Fixed "New backward indexing is too limited"
  ([#6631](https://github.com/nim-lang/Nim/issues/6631))
--- a/changelogs/changelog_1_0_0.md
+++ b/changelogs/changelog_1_0_0.md
@@ -22,7 +22,7 @@

 - We removed `unicode.Rune16` without any deprecation period as the name
  was wrong (see the [RFC](https://github.com/nim-lang/RFCs/issues/151) for details)
-  and we didn't find any usage of it in the wild. If you still need it, add this
+  and we didn't find any usages of it in the wild. If you still need it, add this
  piece of code to your project:
 ```nim
 type
--- a/changelogs/changelog_1_0_2.md
+++ b/changelogs/changelog_1_0_2.md
@@ -11,7 +11,7 @@
 * Fixed "Assertion error when running `nim check` on compiler/nim.nim" [#12281](https://github.com/nim-lang/Nim/issues/12281)
 * Fixed "Compiler crash with empty array and generic instantiation with int as parameter" [#12264](https://github.com/nim-lang/Nim/issues/12264)
 * Fixed "Regression in JS backend codegen "Error: request to generate code for .compileTime proc"" [#12240](https://github.com/nim-lang/Nim/issues/12240)
-* Fix how `relativePath` handles case sensitivity
+* Fix how `relativePath` handle case sensitiviy
 * Fixed "SIGSEGV in compiler when using generic types and seqs" [#12336](https://github.com/nim-lang/Nim/issues/12336)
 * Fixed "[1.0.0] weird interaction between `import os` and casting integer to char on macosx trigger bad codegen" [#12291](https://github.com/nim-lang/Nim/issues/12291)
 * VM: no special casing for big endian machines
@@ -43,7 +43,7 @@
 * threadpool: fix link in docs (#12258)
 * Fix spellings (#12277)
 * fix #12278, don't expose internal PCRE documentation
-* Fixed "Documentation of quitprocs is wrong" [#12279](https://github.com/nim-lang/Nim/issues/12279)
+* Fixed "Documentation of quitprocs is wrong" [#12279(https://github.com/nim-lang/Nim/issues/12279)
 * Fix typo in docs
 * Fix reference to parseSpec proc in readme
 * [doc/tut1] removed discard discussion in comments
--- a/changelogs/changelog_1_2_0.md
+++ b/changelogs/changelog_1_2_0.md
@@ -169,7 +169,7 @@ echo f
 - The Nim compiler now supports a new pragma called ``.localPassc`` to
  pass specific compiler options to the C(++) backend for the C(++) file
  that was produced from the current Nim module.
- The compiler now infers "sink parameters". To disable this for a specific routine,
+- The compiler now inferes "sink parameters". To disable this for a specific routine,
  annotate it with `.nosinks`. To disable it for a section of code, use
  `{.push sinkInference: off.}`...`{.pop.}`.
 - The compiler now supports a new switch `--panics:on` that turns runtime
@@ -261,7 +261,7 @@ echo f
  ([#12812](https://github.com/nim-lang/Nim/issues/12812))
 - Fixed "Produce static/const initializations for variables when possible"
  ([#12216](https://github.com/nim-lang/Nim/issues/12216))
- Fixed "Assigning discriminator field leads to internal assert with --gc:destructors"
+- Fixed "Assigning descriminator field leads to internal assert with --gc:destructors"
  ([#12821](https://github.com/nim-lang/Nim/issues/12821))
 - Fixed "nimsuggest `use` command does not return all instances of symbol"
  ([#12832](https://github.com/nim-lang/Nim/issues/12832))
--- a/changelogs/changelog_2_0_0.md
+++ b/changelogs/changelog_2_0_0.md
@@ -283,7 +283,7 @@ The definition of `"strictFuncs"` was changed.
 The old definition was roughly: "A store to a ref/ptr deref is forbidden unless it's coming from a `var T` parameter".
 The new definition is: "A store to a ref/ptr deref is forbidden."

-This new definition is much easier to understand, the price is some expressiveness. The following code used to be
+This new definition is much easier to understand, the price is some expressitivity. The following code used to be
 accepted:

 ```nim
--- a/changelogs/changelog_2_0_0_details.md
+++ b/changelogs/changelog_2_0_0_details.md
@@ -72,7 +72,7 @@
 - `shallowCopy` and `shallow` are removed for ARC/ORC. Use `move` when possible or combine assignment and
 `sink` for optimization purposes.

- The experimental `nimPreviewDotLikeOps` switch is going to be removed or deprecated because it didn't fulfill its promises.
+- The experimental `nimPreviewDotLikeOps` switch is going to be removed or deprecated because it didn't fullfill its promises.

 - The `{.this.}` pragma, deprecated since 0.19, has been removed.
 - `nil` literals can no longer be directly assigned to variables or fields of `distinct` pointer types. They must be converted instead.
@@ -205,7 +205,7 @@
  proc prc(): int =
    123

-  iterator iter(): int {.closure.} =
+  iterator iter(): int =
    yield 123

  proc takesProc[T: proc](x: T) = discard
--- a/changelogs/changelog_2_2_0.md
+++ b/changelogs/changelog_2_2_0.md
@@ -1,248 +1,12 @@
-# v2.2.0 - 2024-10-02
-
+# v2.2.0 - 2023-mm-dd

 ## 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.
--- a/changelogs/changelog_X_XX_X.md
+++ b/changelogs/changelog_X_XX_X.md
@@ -1,4 +1,4 @@
-# v2.xx.x - yyyy-mm-dd
+# v1.xx.x - yyyy-mm-dd

 This is an example file.
 The changes should go to changelog.md!
--- a/compiler/aliases.nim
+++ b/compiler/aliases.nim
@@ -10,9 +10,7 @@
 ## Simple alias analysis for the HLO and the code generators.

 import
-  ast, astalgo, types, trees
-
-import std/intsets
+  ast, astalgo, types, trees, intsets

 when defined(nimPreviewSlimSystem):
  import std/assertions
@@ -51,16 +49,14 @@ proc isPartOfAux(a, b: PType, marker: var IntSet): TAnalysisResult =
  if compareTypes(a, b, dcEqIgnoreDistinct): return arYes
  case a.kind
  of tyObject:
-    if a.baseClass != nil:
-      result = isPartOfAux(a.baseClass.skipTypes(skipPtrs), b, marker)
+    if a[0] != nil:
+      result = isPartOfAux(a[0].skipTypes(skipPtrs), b, marker)
    if result == arNo: result = isPartOfAux(a.n, b, marker)
  of tyGenericInst, tyDistinct, tyAlias, tySink:
-    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)
+    result = isPartOfAux(lastSon(a), b, marker)
+  of tyArray, tySet, tyTuple:
+    for i in 0..<a.len:
+      result = isPartOfAux(a[i], b, marker)
      if result == arYes: return
  else: discard

--- a/compiler/ast.nim
+++ b/compiler/ast.nim
--- a/compiler/ast2nif.nim
+++ b/compiler/ast2nif.nim
--- a/compiler/astalgo.nim
+++ b/compiler/astalgo.nim
@@ -12,18 +12,23 @@
 # the data structures here are used in various places of the compiler.

 import
-  ast, astyaml, options, lineinfos, idents, rodutils,
+  ast, hashes, intsets, options, lineinfos, ropes, idents, rodutils,
  msgs

-import std/[hashes, intsets]
-import std/strutils except addf
-
-export astyaml.treeToYaml, astyaml.typeToYaml, astyaml.symToYaml, astyaml.lineInfoToStr
+import strutils except addf

 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:
@@ -31,6 +36,15 @@ 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)
@@ -65,9 +79,21 @@ 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
+proc mustRehash*(length, counter: int): bool
+proc nextTry*(h, maxHash: Hash): Hash {.inline.}

 # ------------- table[int, int] ---------------------------------------------
 const
@@ -214,7 +240,175 @@ proc getNamedParamFromList*(list: PNode, ident: PIdent): PSym =
 proc hashNode(p: RootRef): Hash =
  result = hash(cast[pointer](p))

-import std/tables
+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:
+    result = ""
+    sonsRope = rope("null")
+  elif containsOrIncl(marker, n.id):
+    result = ""
+    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

 const backrefStyle = "\e[90m"
 const enumStyle = "\e[34m"
@@ -378,12 +572,14 @@ proc value(this: var DebugPrinter; value: PType) =
    this.key "n"
    this.value value.n

-  this.key "sons"
-  this.openBracket
-  for i, a in value.ikids:
-    if i > 0: this.comma
-    this.value a
-  this.closeBracket
+  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

  if value.n != nil:
    this.key "n"
@@ -452,32 +648,35 @@ proc value(this: var DebugPrinter; value: PNode) =


 proc debug(n: PSym; conf: ConfigRef) =
-  var this = DebugPrinter(
-    visited: initTable[pointer, int](),
-    renderSymType: true,
-    useColor: not defined(windows)
-  )
+  var this: DebugPrinter
+  this.visited = initTable[pointer, int]()
+  this.renderSymType = true
+  this.useColor = not defined(windows)
  this.value(n)
  echo($this.res)

 proc debug(n: PType; conf: ConfigRef) =
-  var this = DebugPrinter(
-    visited: initTable[pointer, int](),
-    renderSymType: true,
-    useColor: not defined(windows)
-  )
+  var this: DebugPrinter
+  this.visited = initTable[pointer, int]()
+  this.renderSymType = true
+  this.useColor = not defined(windows)
  this.value(n)
  echo($this.res)

 proc debug(n: PNode; conf: ConfigRef) =
-  var this = DebugPrinter(
-    visited: initTable[pointer, int](),
-    renderSymType: false,
-    useColor: not defined(windows)
-  )
+  var this: DebugPrinter
+  this.visited = initTable[pointer, int]()
+  #this.renderSymType = true
+  this.useColor = not defined(windows)
  this.value(n)
  echo($this.res)

+proc nextTry(h, maxHash: Hash): Hash =
+  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
+  # random-number generation for proof).
+
 proc objectSetContains*(t: TObjectSet, obj: RootRef): bool =
  # returns true whether n is in t
  var h: Hash = hashNode(obj) and high(t.data) # start with real hash value
@@ -525,6 +724,95 @@ proc objectSetContainsOrIncl*(t: var TObjectSet, obj: RootRef): bool =
  inc(t.counter)
  result = false

+proc strTableContains*(t: TStrTable, n: PSym): bool =
+  var h: Hash = n.name.h and high(t.data) # start with real hash value
+  while t.data[h] != nil:
+    if (t.data[h] == n):
+      return true
+    h = nextTry(h, high(t.data))
+  result = false
+
+proc strTableRawInsert(data: var seq[PSym], n: PSym) =
+  var h: Hash = n.name.h and high(data)
+  while data[h] != nil:
+    if data[h] == n:
+      # allowed for 'export' feature:
+      #InternalError(n.info, "StrTableRawInsert: " & n.name.s)
+      return
+    h = nextTry(h, high(data))
+  assert(data[h] == nil)
+  data[h] = n
+
+proc symTabReplaceRaw(data: var seq[PSym], prevSym: PSym, newSym: PSym) =
+  assert prevSym.name.h == newSym.name.h
+  var h: Hash = prevSym.name.h and high(data)
+  while data[h] != nil:
+    if data[h] == prevSym:
+      data[h] = newSym
+      return
+    h = nextTry(h, high(data))
+  assert false
+
+proc symTabReplace*(t: var TStrTable, prevSym: PSym, newSym: PSym) =
+  symTabReplaceRaw(t.data, prevSym, newSym)
+
+proc strTableEnlarge(t: var TStrTable) =
+  var n: seq[PSym]
+  newSeq(n, t.data.len * GrowthFactor)
+  for i in 0..high(t.data):
+    if t.data[i] != nil: strTableRawInsert(n, t.data[i])
+  swap(t.data, n)
+
+proc strTableAdd*(t: var TStrTable, n: PSym) =
+  if mustRehash(t.data.len, t.counter): strTableEnlarge(t)
+  strTableRawInsert(t.data, n)
+  inc(t.counter)
+
+proc strTableInclReportConflict*(t: var TStrTable, n: PSym;
+                                 onConflictKeepOld = false): PSym =
+  # if `t` has a conflicting symbol (same identifier as `n`), return it
+  # otherwise return `nil`. Incl `n` to `t` unless `onConflictKeepOld = true`
+  # and a conflict was found.
+  assert n.name != nil
+  var h: Hash = n.name.h and high(t.data)
+  var replaceSlot = -1
+  while true:
+    var it = t.data[h]
+    if it == nil: break
+    # Semantic checking can happen multiple times thanks to templates
+    # and overloading: (var x=@[]; x).mapIt(it).
+    # So it is possible the very same sym is added multiple
+    # times to the symbol table which we allow here with the 'it == n' check.
+    if it.name.id == n.name.id:
+      if it == n: return nil
+      replaceSlot = h
+    h = nextTry(h, high(t.data))
+  if replaceSlot >= 0:
+    result = t.data[replaceSlot] # found it
+    if not onConflictKeepOld:
+      t.data[replaceSlot] = n # overwrite it with newer definition!
+    return result # but return the old one
+  elif mustRehash(t.data.len, t.counter):
+    strTableEnlarge(t)
+    strTableRawInsert(t.data, n)
+  else:
+    assert(t.data[h] == nil)
+    t.data[h] = n
+  inc(t.counter)
+  result = nil
+
+proc strTableIncl*(t: var TStrTable, n: PSym;
+                   onConflictKeepOld = false): bool {.discardable.} =
+  result = strTableInclReportConflict(t, n, onConflictKeepOld) != nil
+
+proc strTableGet*(t: TStrTable, name: PIdent): PSym =
+  var h: Hash = name.h and high(t.data)
+  while true:
+    result = t.data[h]
+    if result == nil: break
+    if result.name.id == name.id: break
+    h = nextTry(h, high(t.data))
+

 type
  TIdentIter* = object # iterator over all syms with same identifier
@@ -606,75 +894,124 @@ proc initTabIter*(ti: var TTabIter, tab: TStrTable): PSym =
    result = nextIter(ti, tab)

 iterator items*(tab: TStrTable): PSym =
-  var it: TTabIter = default(TTabIter)
+  var it: TTabIter
  var s = initTabIter(it, tab)
  while s != nil:
    yield s
    s = nextIter(it, tab)

-proc isNil(x: ItemId): bool {.inline.} =
-  x.module == 0 and x.item == 0
-
-proc hasEmptySlot[T](data: TIdPairSeq[T]): bool =
+proc hasEmptySlot(data: TIdPairSeq): bool =
  for h in 0..high(data):
-    if isNil(data[h].key):
+    if data[h].key == nil:
      return true
  result = false

-proc idTableRawGet[T](t: TIdTable[T], key: int): int =
+proc idTableRawGet(t: TIdTable, key: int): int =
  var h: Hash
  h = key and high(t.data)    # start with real hash value
-  while not isNil(t.data[h].key):
-    if toId(t.data[h].key) == key:
+  while t.data[h].key != nil:
+    if t.data[h].key.id == key:
      return h
    h = nextTry(h, high(t.data))
  result = - 1

-proc getOrDefault*[T](t: TIdTable[T], key: ItemId): T =
-  var index = idTableRawGet(t, toId(key))
+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 = default(T)
+  else: result = nil

-template idTableGet*[T](t: TIdTable[T], key: PType | PSym): T =
-  getOrDefault(t, key.itemId)
+proc idTableGet(t: TIdTable, key: int): RootRef =
+  var index = idTableRawGet(t, key)
+  if index >= 0: result = t.data[index].val
+  else: result = nil

-proc idTableRawInsert[T](data: var TIdPairSeq[T], key: ItemId, val: T) =
+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
-  let keyId = toId(key)
-  h = keyId and high(data)
-  while not isNil(data[h].key):
-    assert(toId(data[h].key) != keyId)
+  h = key.id and high(data)
+  while data[h].key != nil:
+    assert(data[h].key.id != key.id)
    h = nextTry(h, high(data))
-  assert(isNil(data[h].key))
+  assert(data[h].key == nil)
  data[h].key = key
  data[h].val = val

-proc `[]=`*[T](t: var TIdTable[T], key: ItemId, val: T) =
+proc idTablePut(t: var TIdTable, key: PIdObj, val: RootRef) =
  var
    index: int
-    n: TIdPairSeq[T]
-  index = idTableRawGet(t, toId(key))
+    n: TIdPairSeq
+  index = idTableRawGet(t, key.id)
  if index >= 0:
-    assert(not isNil(t.data[index].key))
+    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 not isNil(t.data[i].key):
+        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)

-template idTablePut*[T](t: var TIdTable[T], key: PType | PSym, val: T) =
-  t[key.itemId] = val
-
-iterator idTablePairs*[T](t: TIdTable[T]): tuple[key: ItemId, val: T] =
+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)
+    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
@@ -721,6 +1058,14 @@ 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:
--- a/compiler/astdef.nim
+++ b/compiler/astdef.nim
--- a/compiler/astmsgs.nim
+++ b/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.genericHead.sym
+    result = t[0].sym

 proc addDeclaredLoc*(result: var string, conf: ConfigRef; sym: PSym) =
  result.add " [$1 declared in $2]" % [sym.kind.toHumanStr, toFileLineCol(conf, sym.info)]
@@ -24,12 +24,6 @@ proc addDeclaredLoc*(result: var string, conf: ConfigRef; typ: PType) =
    result.add " declared in " & toFileLineCol(conf, typ.sym.info)
  result.add "]"

-proc addTypeNodeDeclaredLoc*(result: var string, conf: ConfigRef; typ: PType) =
-  result.add " [$1" % typ.kind.toHumanStr
-  if typ.sym != nil:
-    result.add " declared in " & toFileLineCol(conf, typ.sym.info)
-  result.add "]"
-
 proc addDeclaredLocMaybe*(result: var string, conf: ConfigRef; typ: PType) =
  if optDeclaredLocs in conf.globalOptions: addDeclaredLoc(result, conf, typ)

--- a/compiler/astyaml.nim
+++ b/compiler/astyaml.nim
@@ -1,154 +0,0 @@
-#
-#
-#           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)
--- a/compiler/backendpragmas.nim
+++ b/compiler/backendpragmas.nim
@@ -0,0 +1,25 @@
+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)
--- a/compiler/bitsets.nim
+++ b/compiler/bitsets.nim
@@ -90,8 +90,3 @@ 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))
--- a/compiler/cbuilderbase.nim
+++ b/compiler/cbuilderbase.nim
@@ -1,164 +0,0 @@
-import ropes, int128
-
-type
-  Snippet* = string
-  Builder* = object
-    buf*: string
-    indents*: int
-
-template newBuilder*(s: string): Builder =
-  Builder(buf: s)
-
-proc extract*(builder: Builder): Snippet =
-  builder.buf
-
-proc add*(builder: var Builder, s: string) =
-  builder.buf.add(s)
-
-proc add*(builder: var Builder, s: char) =
-  builder.buf.add(s)
-
-proc addNewline*(builder: var Builder) =
-  builder.add('\n')
-  for i in 0 ..< builder.indents:
-    builder.add('\t')
-
-proc addLineEnd*(builder: var Builder, s: string) =
-  builder.add(s)
-  builder.addNewline()
-
-proc addLineEndIndent*(builder: var Builder, s: string) =
-  inc builder.indents
-  builder.add(s)
-  builder.addNewline()
-
-proc addDedent*(builder: var Builder, s: string) =
-  if builder.buf.len > 0 and builder.buf[^1] == '\t':
-    builder.buf.setLen(builder.buf.len - 1)
-  builder.add(s)
-  dec builder.indents
-
-proc addLineEndDedent*(builder: var Builder, s: string) =
-  builder.addDedent(s)
-  builder.addNewline()
-
-proc addLineComment*(builder: var Builder, comment: string) =
-  # probably no-op on nifc
-  builder.add("// ")
-  builder.add(comment)
-  builder.addNewline()
-
-proc addIntValue*(builder: var Builder, val: int) =
-  builder.buf.addInt(val)
-
-proc addIntValue*(builder: var Builder, val: int64) =
-  builder.buf.addInt(val)
-
-proc addIntValue*(builder: var Builder, val: uint64) =
-  builder.buf.addInt(val)
-
-proc addIntValue*(builder: var Builder, val: Int128) =
-  builder.buf.addInt128(val)
-
-template cIntValue*(val: int): Snippet = $val
-template cIntValue*(val: int64): Snippet = $val
-template cIntValue*(val: uint64): Snippet = $val
-template cIntValue*(val: Int128): Snippet = $val
-
-template cUintValue*(val: uint): Snippet = $val & "U"
-
-import std/formatfloat
-
-proc addFloatValue*(builder: var Builder, val: float) =
-  builder.buf.addFloat(val)
-
-template cFloatValue*(val: float): Snippet = $val
-
-proc addInt64Literal*(result: var Builder; i: BiggestInt) =
-  if i > low(int64):
-    result.add "IL64($1)" % [rope(i)]
-  else:
-    result.add "(IL64(-9223372036854775807) - IL64(1))"
-
-proc addUint64Literal*(result: var Builder; i: uint64) =
-  result.add rope($i & "ULL")
-
-proc addIntLiteral*(result: var Builder; i: BiggestInt) =
-  if i > low(int32) and i <= high(int32):
-    result.addIntValue(i)
-  elif i == low(int32):
-    # Nim has the same bug for the same reasons :-)
-    result.add "(-2147483647 -1)"
-  elif i > low(int64):
-    result.add "IL64($1)" % [rope(i)]
-  else:
-    result.add "(IL64(-9223372036854775807) - IL64(1))"
-
-proc addIntLiteral*(result: var Builder; i: Int128) =
-  addIntLiteral(result, toInt64(i))
-
-proc cInt64Literal*(i: BiggestInt): Snippet =
-  if i > low(int64):
-    result = "IL64($1)" % [rope(i)]
-  else:
-    result = "(IL64(-9223372036854775807) - IL64(1))"
-
-proc cUint64Literal*(i: uint64): Snippet =
-  result = $i & "ULL"
-
-proc cIntLiteral*(i: BiggestInt): Snippet =
-  if i > low(int32) and i <= high(int32):
-    result = rope(i)
-  elif i == low(int32):
-    # Nim has the same bug for the same reasons :-)
-    result = "(-2147483647 -1)"
-  elif i > low(int64):
-    result = "IL64($1)" % [rope(i)]
-  else:
-    result = "(IL64(-9223372036854775807) - IL64(1))"
-
-proc cIntLiteral*(i: Int128): Snippet =
-  result = cIntLiteral(toInt64(i))
-
-const
-  NimInt* = "NI"
-  NimInt8* = "NI8"
-  NimInt16* = "NI16"
-  NimInt32* = "NI32"
-  NimInt64* = "NI64"
-  CInt* = "int"
-  NimUint* = "NU"
-  NimUint8* = "NU8"
-  NimUint16* = "NU16"
-  NimUint32* = "NU32"
-  NimUint64* = "NU64"
-  NimFloat* = "NF"
-  NimFloat32* = "NF32"
-  NimFloat64* = "NF64"
-  NimFloat128* = "NF128" # not actually defined
-  NimNan* = "NAN"
-  NimInf* = "INF"
-  NimBool* = "NIM_BOOL"
-  NimTrue* = "NIM_TRUE"
-  NimFalse* = "NIM_FALSE"
-  NimChar* = "NIM_CHAR"
-  CChar* = "char"
-  NimCstring* = "NCSTRING"
-  NimNil* = "NIM_NIL"
-  CNil* = "NULL"
-  NimStrlitFlag* = "NIM_STRLIT_FLAG"
-  CVoid* = "void"
-  CPointer* = "void*"
-  CConstPointer* = "NIM_CONST void*"
-
-proc cIntType*(bits: BiggestInt): Snippet =
-  "NI" & $bits
-
-proc cUintType*(bits: BiggestInt): Snippet =
-  "NU" & $bits
-
-type
-  IfBuilderState* = enum
-    WaitingIf, WaitingElseIf, InBlock
-  IfBuilder* = object
-    state*: IfBuilderState
--- a/compiler/cbuilderdecls.nim
+++ b/compiler/cbuilderdecls.nim
@@ -1,668 +0,0 @@
-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.addLineEnd(";")
-
-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.addLineEnd(";")
-
-template addVarWithInitializer(builder: var Builder, kind: VarKind = Local, name: string,
-                               typ: Snippet, initializerBody: typed) =
-  ## adds a variable declaration to the builder, with
-  ## `initializerBody` building the initializer. initializer must be provided
-  builder.addVarHeader(kind)
-  builder.add(typ)
-  builder.add(" ")
-  builder.add(name)
-  builder.add(" = ")
-  initializerBody
-  builder.addLineEnd(";")
-
-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.addLineEnd(";")
-
-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.addIntValue(len)
-  builder.add("]")
-  if initializer.len != 0:
-    builder.add(" = ")
-    builder.add(initializer)
-  builder.addLineEnd(";")
-
-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.addIntValue(len)
-  builder.add("] = ")
-  body
-  builder.addLineEnd(";")
-
-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.addLineEnd(";")
-
-proc addProcTypedef(builder: var Builder, callConv: TCallingConvention, name: string, rettype, params: Snippet) =
-  builder.add("typedef ")
-  builder.add(CallingConvToStr[callConv])
-  builder.add("_PTR(")
-  builder.add(rettype)
-  builder.add(", ")
-  builder.add(name)
-  builder.add(")")
-  builder.add(params)
-  builder.addLineEnd(";")
-
-template addArrayTypedef(builder: var Builder, name: string, len: BiggestInt, 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.addIntValue(len)
-  builder.addLineEnd("];")
-
-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:
-    # positional init - name not used in output (empty allowed for anonymous unions)
-    valueBody
-  of siNamedStruct:
-    # designated init - empty name for anonymous unions (skips .name = prefix)
-    if name.len != 0:
-      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.addIntValue(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.addIntValue(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.addIntValue(field.bitsize)
-  if initializer.len != 0:
-    obj.add(initializer)
-  obj.add(";\n")
-
-proc addProcField(obj: var Builder, callConv: TCallingConvention, name: string, rettype, params: Snippet) =
-  obj.add(CallingConvToStr[callConv])
-  obj.add("_PTR(")
-  obj.add(rettype)
-  obj.add(", ")
-  obj.add(name)
-  obj.add(")")
-  obj.add(params)
-  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.buf.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.buf.len:
-    # no fields were added, add dummy field
-    obj.addField(name = "dummy", typ = CChar)
-  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.buf.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 = CChar)
-  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.buf.len and
-      t.itemId notin m.g.graph.memberProcsPerType:
-    # no fields were added, add dummy field
-    obj.addField(name = "dummy", typ = CChar)
-  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:
-    obj.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")
-
-template addUnionType(obj: var Builder; body: typed) =
-  ## adds a union type i.e. `union { ... }` with fields according to `body`
-  obj.add "union{\n"
-  body
-  obj.add("}")
-
-type DeclVisibility = enum
-  None
-  Extern
-  ExternC
-  ImportLib
-  ExportLib
-  ExportLibVar
-  Private
-  StaticProc
-
-proc addVisibilityPrefix(builder: var Builder, visibility: DeclVisibility) =
-  # internal proc
-  case visibility
-  of None: discard
-  of Extern:
-    builder.add("extern ")
-  of ExternC:
-    builder.add("NIM_EXTERNC ")
-  of ImportLib:
-    builder.add("N_LIB_IMPORT ")
-  of ExportLib:
-    builder.add("N_LIB_EXPORT ")
-  of ExportLibVar:
-    builder.add("N_LIB_EXPORT_VAR ")
-  of Private:
-    builder.add("N_LIB_PRIVATE ")
-  of StaticProc:
-    builder.add("static ")
-
-template addDeclWithVisibility(builder: var Builder, visibility: DeclVisibility, declBody: typed) =
-  ## adds a declaration as in `declBody` with the given visibility
-  builder.addVisibilityPrefix(visibility)
-  declBody
-
-type ProcParamBuilder = object
-  needsComma: bool
-
-proc initProcParamBuilder(builder: var Builder): ProcParamBuilder =
-  result = ProcParamBuilder(needsComma: false)
-  builder.add("(")
-
-proc finishProcParamBuilder(builder: var Builder, params: ProcParamBuilder) =
-  if params.needsComma:
-    builder.add(")")
-  else:
-    builder.add("void)")
-
-template cgDeclFrmt*(s: PSym): string =
-  s.constraint.strVal
-
-proc addParam(builder: var Builder, params: var ProcParamBuilder, name: string, typ: Snippet) =
-  if params.needsComma:
-    builder.add(", ")
-  else:
-    params.needsComma = true
-  builder.add(typ)
-  builder.add(" ")
-  builder.add(name)
-
-proc addParam(builder: var Builder, params: var ProcParamBuilder, param: PSym, typ: Snippet) =
-  if params.needsComma:
-    builder.add(", ")
-  else:
-    params.needsComma = true
-  var modifiedTyp = typ
-  if sfNoalias in param.flags:
-    modifiedTyp.add(" NIM_NOALIAS")
-  if sfCodegenDecl notin param.flags:
-    builder.add(modifiedTyp)
-    builder.add(" ")
-    builder.add(param.loc.snippet)
-  else:
-    builder.add runtimeFormat(param.cgDeclFrmt, [modifiedTyp, param.loc.snippet])
-
-proc addUnnamedParam(builder: var Builder, params: var ProcParamBuilder, typ: Snippet) =
-  if params.needsComma:
-    builder.add(", ")
-  else:
-    params.needsComma = true
-  builder.add(typ)
-
-proc addProcTypedParam(builder: var Builder, paramBuilder: var ProcParamBuilder, callConv: TCallingConvention, name: string, rettype, params: Snippet) =
-  if paramBuilder.needsComma:
-    builder.add(", ")
-  else:
-    paramBuilder.needsComma = true
-  builder.add(CallingConvToStr[callConv])
-  builder.add("_PTR(")
-  builder.add(rettype)
-  builder.add(", ")
-  builder.add(name)
-  builder.add(")")
-  builder.add(params)
-
-proc addVarargsParam(builder: var Builder, params: var ProcParamBuilder) =
-  # does not exist in NIFC, needs to be proc pragma
-  if params.needsComma:
-    builder.add(", ")
-  else:
-    params.needsComma = true
-  builder.add("...")
-
-template addProcParams(builder: var Builder, params: out ProcParamBuilder, body: typed) =
-  params = initProcParamBuilder(builder)
-  body
-  finishProcParamBuilder(builder, params)
-
-type SimpleProcParam = tuple
-  name, typ: string
-
-proc cProcParams(params: varargs[SimpleProcParam]): Snippet =
-  if params.len == 0: return "(void)"
-  result = "("
-  for i in 0 ..< params.len:
-    if i != 0: result.add(", ")
-    result.add(params[i].typ)
-    if params[i].name.len != 0:
-      result.add(" ")
-      result.add(params[i].name)
-  result.add(")")
-
-template addProcHeaderWithParams(builder: var Builder, callConv: TCallingConvention,
-                                 name: string, rettype: Snippet, paramBuilder: typed) =
-  # on nifc should build something like (proc name params type pragmas
-  # with no body given
-  # or enforce this with secondary builder object
-  builder.add(CallingConvToStr[callConv])
-  builder.add("(")
-  builder.add(rettype)
-  builder.add(", ")
-  builder.add(name)
-  builder.add(")")
-  paramBuilder
-
-proc addProcHeader(builder: var Builder, callConv: TCallingConvention,
-                   name: string, rettype, params: Snippet) =
-  # on nifc should build something like (proc name params type pragmas
-  # with no body given
-  # or enforce this with secondary builder object
-  addProcHeaderWithParams(builder, callConv, name, rettype):
-    builder.add(params)
-
-proc addProcHeader(builder: var Builder, name: string, rettype, params: Snippet, isConstructor = false) =
-  # no callconv
-  builder.add(rettype)
-  builder.add(" ")
-  if isConstructor:
-    builder.add("__attribute__((constructor)) ")
-  builder.add(name)
-  builder.add(params)
-
-proc addProcHeader(builder: var Builder, m: BModule, prc: PSym, name: string, params, rettype: Snippet, addAttributes: bool) =
-  # on nifc should build something like (proc name params type pragmas
-  # with no body given
-  # or enforce this with secondary builder object
-  let noreturn = isNoReturn(m, prc)
-  if sfPure in prc.flags and hasDeclspec in extccomp.CC[m.config.cCompiler].props:
-    builder.add("__declspec(naked) ")
-  if noreturn and hasDeclspec in extccomp.CC[m.config.cCompiler].props:
-    builder.add("__declspec(noreturn) ")
-  builder.add(CallingConvToStr[prc.typ.callConv])
-  builder.add("(")
-  builder.add(rettype)
-  builder.add(", ")
-  builder.add(name)
-  builder.add(")")
-  builder.add(params)
-  if addAttributes:
-    if sfPure in prc.flags and hasAttribute in extccomp.CC[m.config.cCompiler].props:
-      builder.add(" __attribute__((naked))")
-    if noreturn and hasAttribute in extccomp.CC[m.config.cCompiler].props:
-      builder.add(" __attribute__((noreturn))")
-
-proc finishProcHeaderAsProto(builder: var Builder) =
-  builder.addLineEnd(";")
-
-template finishProcHeaderWithBody(builder: var Builder, body: typed) =
-  builder.addLineEndIndent(" {")
-  body
-  builder.addLineEndDedent("}")
-  builder.addNewline
-
-proc addProcVar(builder: var Builder, m: BModule, prc: PSym, name: string, params, rettype: Snippet,
-                isStatic = false, ignoreAttributes = false) =
-  # on nifc, builds full variable
-  if isStatic:
-    builder.add("static ")
-  let noreturn = isNoReturn(m, prc)
-  if not ignoreAttributes:
-    if sfPure in prc.flags and hasDeclspec in extccomp.CC[m.config.cCompiler].props:
-      builder.add("__declspec(naked) ")
-    if noreturn and hasDeclspec in extccomp.CC[m.config.cCompiler].props:
-      builder.add("__declspec(noreturn) ")
-  builder.add(CallingConvToStr[prc.typ.callConv])
-  builder.add("_PTR(")
-  builder.add(rettype)
-  builder.add(", ")
-  builder.add(name)
-  builder.add(")")
-  builder.add(params)
-  if not ignoreAttributes:
-    if sfPure in prc.flags and hasAttribute in extccomp.CC[m.config.cCompiler].props:
-      builder.add(" __attribute__((naked))")
-    if noreturn and hasAttribute in extccomp.CC[m.config.cCompiler].props:
-      builder.add(" __attribute__((noreturn))")
-  # ensure we are just adding a variable:
-  builder.addLineEnd(";")
-
-proc addProcVar(builder: var Builder, callConv: TCallingConvention,
-                name: string, params, rettype: Snippet,
-                isStatic = false, isVolatile = false) =
-  # on nifc, builds full variable
-  if isStatic:
-    builder.add("static ")
-  builder.add(CallingConvToStr[callConv])
-  builder.add("_PTR(")
-  builder.add(rettype)
-  builder.add(", ")
-  if isVolatile:
-    builder.add("volatile ")
-  builder.add(name)
-  builder.add(")")
-  builder.add(params)
-  # ensure we are just adding a variable:
-  builder.addLineEnd(";")
-
-proc addProcVar(builder: var Builder,
-                name: string, params, rettype: Snippet,
-                isStatic = false, isVolatile = false) =
-  # no callconv
-  if isStatic:
-    builder.add("static ")
-  builder.add(rettype)
-  builder.add(" (*")
-  if isVolatile:
-    builder.add("volatile ")
-  builder.add(name)
-  builder.add(")")
-  builder.add(params)
-  # ensure we are just adding a variable:
-  builder.addLineEnd(";")
-
-type VarInitializerKind = enum
-  Assignment, CppConstructor
-
-proc addVar(builder: var Builder, m: BModule, s: PSym, name: string, typ: Snippet, kind = Local, visibility: DeclVisibility = None, initializer: Snippet = "", initializerKind: VarInitializerKind = Assignment) =
-  if sfCodegenDecl in s.flags:
-    builder.add(runtimeFormat(s.cgDeclFrmt, [typ, name]))
-    if initializer.len != 0:
-      if initializerKind == Assignment:
-        builder.add(" = ")
-      builder.add(initializer)
-    builder.addLineEnd(";")
-    return
-  if s.kind in {skLet, skVar, skField, skForVar} and s.alignment > 0:
-    builder.add("NIM_ALIGN(" & $s.alignment & ") ")
-  builder.addVisibilityPrefix(visibility)
-  if kind == Threadvar:
-    if optThreads in m.config.globalOptions:
-      let sym = s.typ.sym
-      if sym != nil and sfCppNonPod in sym.flags:
-        builder.add("NIM_THREAD_LOCAL ")
-      else: builder.add("NIM_THREADVAR ")
-  else:
-    builder.addVarHeader(kind)
-  builder.add(typ)
-  if sfRegister in s.flags: builder.add(" register")
-  if sfVolatile in s.flags: builder.add(" volatile")
-  if sfNoalias in s.flags: builder.add(" NIM_NOALIAS")
-  builder.add(" ")
-  builder.add(name)
-  if initializer.len != 0:
-    if initializerKind == Assignment:
-      builder.add(" = ")
-    builder.add(initializer)
-  builder.addLineEnd(";")
-
-proc addInclude(builder: var Builder, value: Snippet) =
-  builder.addLineEnd("#include " & value)
--- a/compiler/cbuilderexprs.nim
+++ b/compiler/cbuilderexprs.nim
@@ -1,259 +0,0 @@
-proc constType(t: Snippet): Snippet =
-  # needs manipulation of `t` in nifc
-  "NIM_CONST " & t
-
-proc constPtrType(t: Snippet): Snippet =
-  t & "* NIM_CONST"
-
-proc ptrConstType(t: Snippet): Snippet =
-  "NIM_CONST " & t & "*"
-
-proc ptrType(t: Snippet): Snippet =
-  t & "*"
-
-proc cppRefType(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 procPtrTypeUnnamed(rettype, params: Snippet): Snippet =
-  rettype & "(*)" & params
-
-proc procPtrTypeUnnamedNimCall(rettype, params: Snippet): Snippet =
-  rettype & "(N_RAW_NIMCALL*)" & params
-
-proc procPtrTypeUnnamed(callConv: TCallingConvention, rettype, params: Snippet): Snippet =
-  CallingConvToStr[callConv] & "_PTR(" & rettype & ", )" & params
-
-type CppCaptureKind = enum None, ByReference, ByCopy
-
-template addCppLambda(builder: var Builder, captures: CppCaptureKind, params: Snippet, body: typed) =
-  builder.add("[")
-  case captures
-  of None: discard
-  of ByReference: builder.add("&")
-  of ByCopy: builder.add("=")
-  builder.add("] ")
-  builder.add(params)
-  builder.addLineEndIndent(" {")
-  body
-  builder.addLineEndDedent("}")
-
-proc cCast(typ, value: Snippet): Snippet =
-  "((" & typ & ") " & value & ")"
-
-proc wrapPar(value: Snippet): Snippet =
-  # used for expression group, no-op on sexp
-  "(" & value & ")"
-
-proc removeSinglePar(value: Snippet): Snippet =
-  # removes a single paren layer expected to exist, to silence Wparentheses-equality
-  assert value[0] == '(' and value[^1] == ')'
-  value[1..^2]
-
-template addCast(builder: var Builder, typ: Snippet, valueBody: typed) =
-  ## adds a cast to `typ` with value built by `valueBody`
-  builder.add "(("
-  builder.add typ
-  builder.add ") "
-  valueBody
-  builder.add ")"
-
-proc cAddr(value: Snippet): Snippet =
-  "(&" & value & ")"
-
-proc cLabelAddr(value: TLabel): Snippet =
-  "&&" & value
-
-proc cDeref(value: Snippet): Snippet =
-  "(*" & value & ")"
-
-proc subscript(a, b: Snippet): Snippet =
-  a & "[" & b & "]"
-
-proc dotField(a, b: Snippet): Snippet =
-  a & "." & b
-
-proc derefField(a, b: Snippet): Snippet =
-  a & "->" & b
-
-type CallBuilder = object
-  needsComma: bool
-
-proc initCallBuilder(builder: var Builder, callee: Snippet): CallBuilder =
-  result = CallBuilder(needsComma: false)
-  builder.add(callee)
-  builder.add("(")
-
-const cArgumentSeparator = ", "
-
-proc addArgumentSeparator(builder: var Builder) =
-  # no-op on NIFC
-  # used by "single argument" builders
-  builder.add(cArgumentSeparator)
-
-template addArgument(builder: var Builder, call: var CallBuilder, valueBody: typed) =
-  if call.needsComma:
-    builder.addArgumentSeparator()
-  else:
-    call.needsComma = true
-  valueBody
-
-proc finishCallBuilder(builder: var Builder, call: CallBuilder) =
-  builder.add(")")
-
-template addCall(builder: var Builder, call: out CallBuilder, callee: Snippet, body: typed) =
-  call = initCallBuilder(builder, callee)
-  body
-  finishCallBuilder(builder, call)
-
-proc addCall(builder: var Builder, callee: Snippet, args: varargs[Snippet]) =
-  builder.add(callee)
-  builder.add("(")
-  if args.len != 0:
-    builder.add(args[0])
-    for i in 1 ..< args.len:
-      builder.add(", ")
-      builder.add(args[i])
-  builder.add(")")
-
-proc cCall(callee: Snippet, args: varargs[Snippet]): Snippet =
-  result = callee
-  result.add("(")
-  if args.len != 0:
-    result.add(args[0])
-    for i in 1 ..< args.len:
-      result.add(", ")
-      result.add(args[i])
-  result.add(")")
-
-proc addSizeof(builder: var Builder, val: Snippet) =
-  builder.add("sizeof(")
-  builder.add(val)
-  builder.add(")")
-
-proc addAlignof(builder: var Builder, val: Snippet) =
-  builder.add("NIM_ALIGNOF(")
-  builder.add(val)
-  builder.add(")")
-
-proc addOffsetof(builder: var Builder, val, member: Snippet) =
-  builder.add("offsetof(")
-  builder.add(val)
-  builder.add(", ")
-  builder.add(member)
-  builder.add(")")
-
-template cSizeof(val: Snippet): Snippet =
-  "sizeof(" & val & ")"
-
-template cAlignof(val: Snippet): Snippet =
-  "NIM_ALIGNOF(" & val & ")"
-
-template cOffsetof(val, member: Snippet): Snippet =
-  "offsetof(" & val & ", " & member & ")"
-
-type TypedBinaryOp = enum
-  Add, Sub, Mul, Div, Mod
-  Shr, Shl, BitAnd, BitOr, BitXor
-
-const typedBinaryOperators: array[TypedBinaryOp, string] = [
-  Add: "+",
-  Sub: "-",
-  Mul: "*",
-  Div: "/",
-  Mod: "%",
-  Shr: ">>",
-  Shl: "<<",
-  BitAnd: "&",
-  BitOr: "|",
-  BitXor: "^"
-]
-
-type TypedUnaryOp = enum
-  Neg, BitNot
-
-const typedUnaryOperators: array[TypedUnaryOp, string] = [
-  Neg: "-",
-  BitNot: "~",
-]
-
-type UntypedBinaryOp = enum
-  LessEqual, LessThan, GreaterEqual, GreaterThan, Equal, NotEqual
-  And, Or
-
-const untypedBinaryOperators: array[UntypedBinaryOp, string] = [
-  LessEqual: "<=",
-  LessThan: "<",
-  GreaterEqual: ">=",
-  GreaterThan: ">",
-  Equal: "==",
-  NotEqual: "!=",
-  And: "&&",
-  Or: "||"
-]
-
-type UntypedUnaryOp = enum
-  Not
-
-const untypedUnaryOperators: array[UntypedUnaryOp, string] = [
-  Not: "!"
-]
-
-proc addOp(builder: var Builder, binOp: TypedBinaryOp, t: Snippet, a, b: Snippet) =
-  builder.add('(')
-  builder.add(a)
-  builder.add(' ')
-  builder.add(typedBinaryOperators[binOp])
-  builder.add(' ')
-  builder.add(b)
-  builder.add(')')
-
-proc addOp(builder: var Builder, unOp: TypedUnaryOp, t: Snippet, a: Snippet) =
-  builder.add('(')
-  builder.add(typedUnaryOperators[unOp])
-  builder.add('(')
-  builder.add(a)
-  builder.add("))")
-
-proc addOp(builder: var Builder, binOp: UntypedBinaryOp, a, b: Snippet) =
-  builder.add('(')
-  builder.add(a)
-  builder.add(' ')
-  builder.add(untypedBinaryOperators[binOp])
-  builder.add(' ')
-  builder.add(b)
-  builder.add(')')
-
-proc addOp(builder: var Builder, unOp: UntypedUnaryOp, a: Snippet) =
-  builder.add('(')
-  builder.add(untypedUnaryOperators[unOp])
-  builder.add('(')
-  builder.add(a)
-  builder.add("))")
-
-template cOp(binOp: TypedBinaryOp, t: Snippet, a, b: Snippet): Snippet =
-  '(' & a & ' ' & typedBinaryOperators[binOp] & ' ' & b & ')'
-
-template cOp(binOp: TypedUnaryOp, t: Snippet, a: Snippet): Snippet =
-  '(' & typedUnaryOperators[binOp] & '(' & a & "))"
-
-template cOp(binOp: UntypedBinaryOp, a, b: Snippet): Snippet =
-  '(' & a & ' ' & untypedBinaryOperators[binOp] & ' ' & b & ')'
-
-template cOp(binOp: UntypedUnaryOp, a: Snippet): Snippet =
-  '(' & untypedUnaryOperators[binOp] & '(' & a & "))"
-
-template cIfExpr(cond, a, b: Snippet): Snippet =
-  # XXX used for `min` and `max`, maybe add nifc primitives for these
-  "(" & cond & " ? " & a & " : " & b & ")"
-
-template cUnlikely(val: Snippet): Snippet =
-  "NIM_UNLIKELY(" & val & ")"
--- a/compiler/cbuilderstmts.nim
+++ b/compiler/cbuilderstmts.nim
@@ -1,329 +0,0 @@
-template addAssignmentWithValue(builder: var Builder, lhs: Snippet, valueBody: typed) =
-  builder.add(lhs)
-  builder.add(" = ")
-  valueBody
-  builder.addLineEnd(";")
-
-template addFieldAssignmentWithValue(builder: var Builder, lhs: Snippet, name: string, valueBody: typed) =
-  builder.add(lhs)
-  builder.add("." & name & " = ")
-  valueBody
-  builder.addLineEnd(";")
-
-template addAssignment(builder: var Builder, lhs, rhs: Snippet) =
-  builder.addAssignmentWithValue(lhs):
-    builder.add(rhs)
-
-template addFieldAssignment(builder: var Builder, lhs: Snippet, name: string, rhs: Snippet) =
-  builder.addFieldAssignmentWithValue(lhs, name):
-    builder.add(rhs)
-
-template addMutualFieldAssignment(builder: var Builder, lhs, rhs: Snippet, name: string) =
-  builder.addFieldAssignmentWithValue(lhs, name):
-    builder.add(rhs)
-    builder.add("." & name)
-
-template addAssignment(builder: var Builder, lhs: Snippet, rhs: int | int64 | uint64 | Int128) =
-  builder.addAssignmentWithValue(lhs):
-    builder.addIntValue(rhs)
-
-template addFieldAssignment(builder: var Builder, lhs: Snippet, name: string, rhs: int | int64 | uint64 | Int128) =
-  builder.addFieldAssignmentWithValue(lhs, name):
-    builder.addIntValue(rhs)
-
-template addDerefFieldAssignment(builder: var Builder, lhs: Snippet, name: string, rhs: Snippet) =
-  builder.add(lhs)
-  builder.add("->" & name & " = ")
-  builder.add(rhs)
-  builder.addLineEnd(";")
-
-template addSubscriptAssignment(builder: var Builder, lhs: Snippet, index: Snippet, rhs: Snippet) =
-  builder.add(lhs)
-  builder.add("[" & index & "] = ")
-  builder.add(rhs)
-  builder.addLineEnd(";")
-
-template addStmt(builder: var Builder, stmtBody: typed) =
-  ## makes an expression built by `stmtBody` into a statement
-  stmtBody
-  builder.addLineEnd(";")
-
-proc addCallStmt(builder: var Builder, callee: Snippet, args: varargs[Snippet]) =
-  builder.addStmt():
-    builder.addCall(callee, args)
-
-# XXX blocks need indent tracker in `Builder` object
-
-template addSingleIfStmt(builder: var Builder, cond: Snippet, body: typed) =
-  builder.add("if (")
-  builder.add(cond)
-  builder.addLineEndIndent(") {")
-  body
-  builder.addLineEndDedent("}")
-
-template addSingleIfStmtWithCond(builder: var Builder, condBody: typed, body: typed) =
-  builder.add("if (")
-  condBody
-  builder.addLineEndIndent(") {")
-  body
-  builder.addLineEndDedent("}")
-
-proc initIfStmt(builder: var Builder): IfBuilder =
-  IfBuilder(state: WaitingIf)
-
-proc finishIfStmt(builder: var Builder, stmt: IfBuilder) =
-  assert stmt.state != InBlock
-  builder.addNewline()
-
-template addIfStmt(builder: var Builder, stmt: out IfBuilder, body: typed) =
-  stmt = initIfStmt(builder)
-  body
-  finishIfStmt(builder, stmt)
-
-proc initElifBranch(builder: var Builder, stmt: var IfBuilder, cond: Snippet) =
-  case stmt.state
-  of WaitingIf:
-    builder.add("if (")
-  of WaitingElseIf:
-    builder.add(" else if (")
-  else: assert false, $stmt.state
-  builder.add(cond)
-  builder.addLineEndIndent(") {")
-  stmt.state = InBlock
-
-proc initElseBranch(builder: var Builder, stmt: var IfBuilder) =
-  assert stmt.state == WaitingElseIf, $stmt.state
-  builder.addLineEndIndent(" else {")
-  stmt.state = InBlock
-
-proc finishBranch(builder: var Builder, stmt: var IfBuilder) =
-  builder.addDedent("}")
-  stmt.state = WaitingElseIf
-
-template addElifBranch(builder: var Builder, stmt: var IfBuilder, cond: Snippet, body: typed) =
-  initElifBranch(builder, stmt, cond)
-  body
-  finishBranch(builder, stmt)
-
-template addElseBranch(builder: var Builder, stmt: var IfBuilder, body: typed) =
-  initElseBranch(builder, stmt)
-  body
-  finishBranch(builder, stmt)
-
-proc initForRange(builder: var Builder, i, start, bound: Snippet, inclusive: bool = false) =
-  builder.add("for (")
-  builder.add(i)
-  builder.add(" = ")
-  builder.add(start)
-  builder.add("; ")
-  builder.add(i)
-  if inclusive:
-    builder.add(" <= ")
-  else:
-    builder.add(" < ")
-  builder.add(bound)
-  builder.add("; ")
-  builder.add(i)
-  builder.addLineEndIndent("++) {")
-
-proc initForStep(builder: var Builder, i, start, bound, step: Snippet, inclusive: bool = false) =
-  builder.add("for (")
-  builder.add(i)
-  builder.add(" = ")
-  builder.add(start)
-  builder.add("; ")
-  builder.add(i)
-  if inclusive:
-    builder.add(" <= ")
-  else:
-    builder.add(" < ")
-  builder.add(bound)
-  builder.add("; ")
-  builder.add(i)
-  builder.add(" += ")
-  builder.add(step)
-  builder.addLineEndIndent(") {")
-
-proc finishFor(builder: var Builder) {.inline.} =
-  builder.addLineEndDedent("}")
-
-template addForRangeExclusive(builder: var Builder, i, start, bound: Snippet, body: typed) =
-  initForRange(builder, i, start, bound, false)
-  body
-  finishFor(builder)
-
-template addForRangeInclusive(builder: var Builder, i, start, bound: Snippet, body: typed) =
-  initForRange(builder, i, start, bound, true)
-  body
-  finishFor(builder)
-
-template addSwitchStmt(builder: var Builder, val: Snippet, body: typed) =
-  builder.add("switch (")
-  builder.add(val)
-  builder.addLineEnd(") {") # no indent
-  body
-  builder.addLineEnd("}")
-
-template addSingleSwitchCase(builder: var Builder, val: Snippet, body: typed) =
-  builder.add("case ")
-  builder.add(val)
-  builder.addLineEndIndent(":")
-  body
-  builder.addLineEndDedent("")
-
-type
-  SwitchCaseState = enum
-    None, Of, Else, Finished
-  SwitchCaseBuilder = object
-    state: SwitchCaseState
-
-proc addCase(builder: var Builder, info: var SwitchCaseBuilder, val: Snippet) =
-  if info.state != Of:
-    assert info.state == None
-    info.state = Of
-  builder.add("case ")
-  builder.add(val)
-  builder.addLineEndIndent(":")
-
-proc addCaseRange(builder: var Builder, info: var SwitchCaseBuilder, first, last: Snippet) =
-  if info.state != Of:
-    assert info.state == None
-    info.state = Of
-  builder.add("case ")
-  builder.add(first)
-  builder.add(" ... ")
-  builder.add(last)
-  builder.addLineEndIndent(":")
-
-proc addCaseElse(builder: var Builder, info: var SwitchCaseBuilder) =
-  assert info.state == None
-  info.state = Else
-  builder.addLineEndIndent("default:")
-
-template addSwitchCase(builder: var Builder, info: out SwitchCaseBuilder, caseBody, body: typed) =
-  info = SwitchCaseBuilder(state: None)
-  caseBody
-  info.state = Finished
-  body
-  builder.addLineEndDedent("")
-
-template addSwitchElse(builder: var Builder, body: typed) =
-  builder.addLineEndIndent("default:")
-  body
-  builder.addLineEndDedent("")
-
-proc addBreak(builder: var Builder) =
-  builder.addLineEnd("break;")
-
-type ScopeBuilder = object
-  inside: bool
-
-proc initScope(builder: var Builder): ScopeBuilder =
-  builder.addLineEndIndent("{")
-  result = ScopeBuilder(inside: true)
-
-proc finishScope(builder: var Builder, scope: var ScopeBuilder) =
-  assert scope.inside, "scope not inited"
-  builder.addLineEndDedent("}")
-  scope.inside = false
-
-template addScope(builder: var Builder, body: typed) =
-  builder.addLineEndIndent("{")
-  body
-  builder.addLineEndDedent("}")
-
-type WhileBuilder = object
-  inside: bool
-
-proc initWhileStmt(builder: var Builder, cond: Snippet): WhileBuilder =
-  builder.add("while (")
-  builder.add(cond)
-  builder.addLineEndIndent(") {")
-  result = WhileBuilder(inside: true)
-
-proc finishWhileStmt(builder: var Builder, stmt: var WhileBuilder) =
-  assert stmt.inside, "while stmt not inited"
-  builder.addLineEndDedent("}")
-  stmt.inside = false
-
-template addWhileStmt(builder: var Builder, cond: Snippet, body: typed) =
-  builder.add("while (")
-  builder.add(cond)
-  builder.addLineEndIndent(") {")
-  body
-  builder.addLineEndDedent("}")
-
-proc addLabel(builder: var Builder, name: TLabel) =
-  builder.add(name)
-  builder.addLineEnd(": ;")
-
-proc addReturn(builder: var Builder) =
-  builder.addLineEnd("return;")
-
-proc addReturn(builder: var Builder, value: Snippet) =
-  builder.add("return ")
-  builder.add(value)
-  builder.addLineEnd(";")
-
-proc addGoto(builder: var Builder, label: TLabel) =
-  builder.add("goto ")
-  builder.add(label)
-  builder.addLineEnd(";")
-
-proc addComputedGoto(builder: var Builder, value: Snippet) =
-  builder.add("goto *")
-  builder.add(value)
-  builder.addLineEnd(";")
-
-proc addIncr(builder: var Builder, val: Snippet) =
-  builder.add(val)
-  builder.addLineEnd("++;")
-
-proc addDecr(builder: var Builder, val: Snippet) =
-  builder.add(val)
-  builder.addLineEnd("--;")
-
-proc addInPlaceOp(builder: var Builder, binOp: TypedBinaryOp, t: Snippet, a, b: Snippet) =
-  builder.add(a)
-  builder.add(' ')
-  builder.add(typedBinaryOperators[binOp])
-  builder.add("= ")
-  builder.add(b)
-  builder.addLineEnd(";")
-
-proc addInPlaceOp(builder: var Builder, binOp: UntypedBinaryOp, a, b: Snippet) =
-  builder.add(a)
-  builder.add(' ')
-  builder.add(untypedBinaryOperators[binOp])
-  builder.add("= ")
-  builder.add(b)
-  builder.addLineEnd(";")
-
-proc cInPlaceOp(binOp: TypedBinaryOp, t: Snippet, a, b: Snippet): Snippet =
-  result = ""
-  result.add(a)
-  result.add(' ')
-  result.add(typedBinaryOperators[binOp])
-  result.add("= ")
-  result.add(b)
-  result.add(";\n")
-
-proc cInPlaceOp(binOp: UntypedBinaryOp, a, b: Snippet): Snippet =
-  result = ""
-  result.add(a)
-  result.add(' ')
-  result.add(untypedBinaryOperators[binOp])
-  result.add("= ")
-  result.add(b)
-  result.add(";\n")
-
-template addCPragma(builder: var Builder, val: Snippet) =
-  builder.addNewline()
-  builder.add("#pragma ")
-  builder.add(val)
-  builder.addNewline()
-
-proc addDiscard(builder: var Builder, val: Snippet) =
-  builder.add("(void)")
-  builder.add(val)
-  builder.addLineEnd(";")
--- a/compiler/ccgcalls.nim
+++ b/compiler/ccgcalls.nim
@@ -76,119 +76,78 @@ 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 destroyArg =
-      if dtor.typ.firstParamType.kind == tyVar:
-        cAddr(rdLoc(tmp))
-      else:
-        rdLoc(tmp)
-    let destroy = cCall(callee, destroyArg)
-    raiseExitCleanup(p, destroy)
-    result = true
-  else:
-    result = false
-
 proc fixupCall(p: BProc, le, ri: PNode, d: var TLoc,
-               result: var Builder, call: var CallBuilder) =
+               callee, params: Rope) =
  let canRaise = p.config.exc == excGoto and canRaiseDisp(p, ri[0])
  genLineDir(p, ri)
+  var pl = callee & "(" & params
  # getUniqueType() is too expensive here:
  var typ = skipTypes(ri[0].typ, abstractInst)
-  if typ.returnType != nil:
-    var flags: TAssignmentFlags = {}
-    if typ.returnType.kind in {tyOpenArray, tyVarargs}:
-      # perhaps generate no temp if the call doesn't have side effects
-      flags.incl needTempForOpenArray
+  if typ[0] != nil:
    if isInvalidReturnType(p.config, typ):
+      if params.len != 0: 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: d = getTemp(p, typ.returnType, needsInit=true)
+        if d.k == locNone: d = getTemp(p, typ[0], needsInit=true)
        elif d.k notin {locTemp} and not hasNoInit(ri):
          # reset before pass as 'result' var:
          discard "resetLoc(p, d)"
-        let rad = addrLoc(p.config, d)
-        result.addArgument(call):
-          result.add(rad)
-        result.finishCallBuilder(call)
-        p.s(cpsStmts).addStmt():
-          p.s(cpsStmts).add(extract(result))
+        pl.add(addrLoc(p.config, d))
+        pl.add(");\n")
+        line(p, cpsStmts, pl)
      else:
-        var tmp: TLoc = getTemp(p, typ.returnType, needsInit=true)
-        let ratmp = addrLoc(p.config, tmp)
-        result.addArgument(call):
-          result.add(ratmp)
-        result.finishCallBuilder(call)
-        p.s(cpsStmts).addStmt():
-          p.s(cpsStmts).add(extract(result))
+        var tmp: TLoc = getTemp(p, typ[0], needsInit=true)
+        pl.add(addrLoc(p.config, tmp))
+        pl.add(");\n")
+        line(p, cpsStmts, pl)
        genAssignment(p, d, tmp, {}) # no need for deep copying
      if canRaise: raiseExit(p)
    else:
-      result.finishCallBuilder(call)
+      pl.add(")")
      if p.module.compileToCpp:
        if 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.snippet = extract(result)
+          d.r = pl
          excl d.flags, lfSingleUse
        else:
-          if d.k == locNone and p.splitDecls == 0 and p.config.exc != excGoto:
-            d = getTempCpp(p, typ.returnType, extract(result))
+          if d.k == locNone and p.splitDecls == 0:
+            d = getTempCpp(p, typ[0], pl)
          else:
-            if d.k == locNone: d = getTemp(p, typ.returnType)
+            if d.k == locNone: d = getTemp(p, typ[0])
            var list = initLoc(locCall, d.lode, OnUnknown)
-            list.snippet = extract(result)
-            genAssignment(p, d, list, {needAssignCall}) # no need for deep copying
+            list.r = pl
+            genAssignment(p, d, list, {}) # no need for deep copying
            if canRaise: raiseExit(p)

      elif isHarmlessStore(p, canRaise, d):
-        var useTemp = false
-        if d.k == locNone:
-          useTemp = true
-          d = getTemp(p, typ.returnType)
+        if d.k == locNone: d = getTemp(p, typ[0])
        assert(d.t != nil)        # generate an assignment to d:
        var list = initLoc(locCall, d.lode, OnUnknown)
-        list.snippet = extract(result)
-        genAssignment(p, d, list, flags+{needAssignCall}) # no need for deep copying
-        if canRaise:
-          if not (useTemp and cleanupTemp(p, typ.returnType, d)):
-            raiseExit(p)
+        list.r = pl
+        genAssignment(p, d, list, {}) # no need for deep copying
+        if canRaise: raiseExit(p)
      else:
-        var tmp: TLoc = getTemp(p, typ.returnType, needsInit=true)
+        var tmp: TLoc = getTemp(p, typ[0], needsInit=true)
        var list = initLoc(locCall, d.lode, OnUnknown)
-        list.snippet = extract(result)
-        genAssignment(p, tmp, list, flags+{needAssignCall}) # no need for deep copying
-        if canRaise:
-          if not cleanupTemp(p, typ.returnType, tmp):
-            raiseExit(p)
+        list.r = pl
+        genAssignment(p, tmp, list, {}) # no need for deep copying
+        if canRaise: raiseExit(p)
        genAssignment(p, d, tmp, {})
  else:
-    finishCallBuilder(result, call)
-    p.s(cpsStmts).addStmt():
-      p.s(cpsStmts).add(extract(result))
+    pl.add(");\n")
+    line(p, cpsStmts, pl)
    if canRaise: raiseExit(p)

-proc genBoundsCheck(p: BProc; arr, a, b: TLoc; arrTyp: PType)
+proc genBoundsCheck(p: BProc; arr, a, b: TLoc)

 proc reifiedOpenArray(n: PNode): bool {.inline.} =
  var x = n
-  while true:
-    case x.kind
-    of {nkAddr, nkHiddenAddr, nkHiddenDeref}:
-      x = x[0]
-    of nkHiddenStdConv:
-      x = x[1]
-    else:
-      break
+  while x.kind in {nkAddr, nkHiddenAddr, nkHiddenStdConv, nkHiddenDeref}:
+    x = x[0]
  if x.kind == nkSym and x.sym.kind == skParam:
    result = false
  else:
@@ -198,57 +157,54 @@ proc genOpenArraySlice(p: BProc; q: PNode; formalType, destType: PType; prepareF
  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 `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)
+    genBoundsCheck(p, a, b, c)
  if prepareForMutation:
-    let bra = byRefLoc(p, a)
-    p.s(cpsStmts).addCallStmt(cgsymValue(p.module, "nimPrepareStrMutationV2"),
-      bra)
+    linefmt(p, cpsStmts, "#nimPrepareStrMutationV2($1);$n", [byRefLoc(p, a)])
+  let ty = skipTypes(a.t, abstractVar+{tyPtr})
  let dest = getTypeDesc(p.module, destType)
-  let ra = rdLoc(a)
-  let rb = rdLoc(b)
-  let rc = rdLoc(c)
-  let lengthExpr = cOp(Add, NimInt, cOp(Sub, NimInt, rc, rb), cIntValue(1))
+  let lengthExpr = "($1)-($2)+1" % [rdLoc(c), rdLoc(b)]
  case ty.kind
  of tyArray:
    let first = toInt64(firstOrd(p.config, ty))
    if first == 0:
-      result = (cCast(ptrType(dest), cOp(Add, NimInt, ra, rb)), lengthExpr)
+      result = ("($3*)(($1)+($2))" % [rdLoc(a), rdLoc(b), dest],
+                lengthExpr)
    else:
-      let lit = cIntLiteral(first)
-      result = (cCast(ptrType(dest), cOp(Add, NimInt, ra, cOp(Sub, NimInt, rb, lit))), lengthExpr)
+      var lit = newRopeAppender()
+      intLiteral(first, lit)
+      result = ("($4*)($1)+(($2)-($3))" %
+        [rdLoc(a), rdLoc(b), lit, dest],
+        lengthExpr)
  of tyOpenArray, tyVarargs:
-    let data = if reifiedOpenArray(q[1]): dotField(ra, "Field0") else: ra
-    result = (cCast(ptrType(dest), cOp(Add, NimInt, data, rb)), lengthExpr)
+    if reifiedOpenArray(q[1]):
+      result = ("($3*)($1.Field0)+($2)" % [rdLoc(a), rdLoc(b), dest],
+                lengthExpr)
+    else:
+      result = ("($3*)($1)+($2)" % [rdLoc(a), rdLoc(b), dest],
+                lengthExpr)
  of tyUncheckedArray, tyCstring:
-    result = (cCast(ptrType(dest), cOp(Add, NimInt, ra, rb)), lengthExpr)
+    result = ("($3*)($1)+($2)" % [rdLoc(a), rdLoc(b), dest],
+              lengthExpr)
  of tyString, tySequence:
    let atyp = skipTypes(a.t, abstractInst)
    if formalType.skipTypes(abstractInst).kind in {tyVar} and atyp.kind == tyString and
        optSeqDestructors in p.config.globalOptions:
-      let bra = byRefLoc(p, a)
-      p.s(cpsStmts).addCallStmt(cgsymValue(p.module, "nimPrepareStrMutationV2"),
-        bra)
-    var val: Snippet
+      linefmt(p, cpsStmts, "#nimPrepareStrMutationV2($1);$n", [byRefLoc(p, a)])
    if atyp.kind in {tyVar} and not compileToCpp(p.module):
-      val = cDeref(ra)
+      result = ("(($5) ? (($4*)(*$1)$3+($2)) : NIM_NIL)" %
+                  [rdLoc(a), rdLoc(b), dataField(p), dest, dataFieldAccessor(p, "*" & rdLoc(a))],
+                lengthExpr)
    else:
-      val = ra
-    result = (
-      cIfExpr(dataFieldAccessor(p, val),
-        cCast(ptrType(dest), cOp(Add, NimInt, dataField(p, val), rb)),
-        NimNil),
-      lengthExpr)
+      result = ("(($5) ? (($4*)$1$3+($2)) : NIM_NIL)" %
+                  [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 Builder) =
+proc openArrayLoc(p: BProc, formalType: PType, n: PNode; result: var Rope) =
  var q = skipConv(n)
  var skipped = false
  while q.kind == nkStmtListExpr and q.len > 0:
@@ -262,67 +218,45 @@ proc openArrayLoc(p: BProc, formalType: PType, n: PNode; result: var Builder) =
        for i in 0..<q.len-1:
          genStmts(p, q[i])
        q = q.lastSon
-    let (x, y) = genOpenArraySlice(p, q, formalType, n.typ.elementType)
-    result.add(x)
-    result.addArgumentSeparator()
-    result.add(y)
+    let (x, y) = genOpenArraySlice(p, q, formalType, n.typ[0])
+    result.add x & ", " & y
  else:
-    var a = initLocExpr(p, if n.kind == nkHiddenStdConv: n[1] else: n)
+    var a: TLoc = initLocExpr(p, if n.kind == nkHiddenStdConv: n[1] else: n)
    case skipTypes(a.t, abstractVar+{tyStatic}).kind
    of tyOpenArray, tyVarargs:
-      let ra = rdLoc(a)
      if reifiedOpenArray(n):
        if a.t.kind in {tyVar, tyLent}:
-          result.add(derefField(ra, "Field0"))
-          result.addArgumentSeparator()
-          result.add(derefField(ra, "Field1"))
+          result.add "$1->Field0, $1->Field1" % [rdLoc(a)]
        else:
-          result.add(dotField(ra, "Field0"))
-          result.addArgumentSeparator()
-          result.add(dotField(ra, "Field1"))
+          result.add "$1.Field0, $1.Field1" % [rdLoc(a)]
      else:
-        result.add(ra)
-        result.addArgumentSeparator()
-        result.add(ra & "Len_0")
+        result.add "$1, $1Len_0" % [rdLoc(a)]
    of tyString, tySequence:
      let ntyp = skipTypes(n.typ, abstractInst)
      if formalType.skipTypes(abstractInst).kind in {tyVar} and ntyp.kind == tyString and
          optSeqDestructors in p.config.globalOptions:
-        let bra = byRefLoc(p, a)
-        p.s(cpsStmts).addCallStmt(cgsymValue(p.module, "nimPrepareStrMutationV2"),
-          bra)
+        linefmt(p, cpsStmts, "#nimPrepareStrMutationV2($1);$n", [byRefLoc(p, a)])
      if ntyp.kind in {tyVar} and not compileToCpp(p.module):
-        let ra = a.rdLoc
-        var t = TLoc(snippet: cDeref(ra))
-        let lt = lenExpr(p, t)
-        result.add(cIfExpr(dataFieldAccessor(p, t.snippet), dataField(p, t.snippet), NimNil))
-        result.addArgumentSeparator()
-        result.add(lt)
+        var t: TLoc
+        t.r = "(*$1)" % [a.rdLoc]
+        result.add "($4) ? ((*$1)$3) : NIM_NIL, $2" %
+                     [a.rdLoc, lenExpr(p, t), dataField(p),
+                      dataFieldAccessor(p, "*" & a.rdLoc)]
      else:
-        let ra = a.rdLoc
-        let la = lenExpr(p, a)
-        result.add(cIfExpr(dataFieldAccessor(p, ra), dataField(p, ra), NimNil))
-        result.addArgumentSeparator()
-        result.add(la)
+        result.add "($4) ? ($1$3) : NIM_NIL, $2" %
+                     [a.rdLoc, lenExpr(p, a), dataField(p), dataFieldAccessor(p, a.rdLoc)]
    of tyArray:
-      let ra = rdLoc(a)
-      result.add(ra)
-      result.addArgumentSeparator()
-      result.addIntValue(lengthOrd(p.config, a.t))
+      result.add "$1, $2" % [rdLoc(a), rope(lengthOrd(p.config, a.t))]
    of tyPtr, tyRef:
-      case elementType(a.t).kind
+      case lastSon(a.t).kind
      of tyString, tySequence:
-        let ra = a.rdLoc
-        var t = TLoc(snippet: cDeref(ra))
-        let lt = lenExpr(p, t)
-        result.add(cIfExpr(dataFieldAccessor(p, t.snippet), dataField(p, t.snippet), NimNil))
-        result.addArgumentSeparator()
-        result.add(lt)
+        var t: TLoc
+        t.r = "(*$1)" % [a.rdLoc]
+        result.add "($4) ? ((*$1)$3) : NIM_NIL, $2" %
+                     [a.rdLoc, lenExpr(p, t), dataField(p),
+                      dataFieldAccessor(p, "*" & a.rdLoc)]
      of tyArray:
-        let ra = rdLoc(a)
-        result.add(ra)
-        result.addArgumentSeparator()
-        result.addIntValue(lengthOrd(p.config, elementType(a.t)))
+        result.add "$1, $2" % [rdLoc(a), rope(lengthOrd(p.config, lastSon(a.t)))]
      else:
        internalError(p.config, "openArrayLoc: " & typeToString(a.t))
    else: internalError(p.config, "openArrayLoc: " & typeToString(a.t))
@@ -338,61 +272,46 @@ proc withTmpIfNeeded(p: BProc, a: TLoc, needsTmp: bool): TLoc =
  else:
    result = a

-proc expressionsNeedsTmp(p: BProc, a: TLoc): TLoc =
+proc literalsNeedsTmp(p: BProc, a: TLoc): TLoc =
  result = getTemp(p, a.lode.typ, needsInit=false)
  genAssignment(p, result, a, {})

-proc genArgStringToCString(p: BProc, n: PNode; result: var Builder; needsTmp: bool) {.inline.} =
-  var a = initLocExpr(p, n[0])
-  let ra = withTmpIfNeeded(p, a, needsTmp).rdLoc
-  result.addCall(cgsymValue(p.module, "nimToCStringConv"), ra)
+proc genArgStringToCString(p: BProc, n: PNode; result: var Rope; needsTmp: bool) {.inline.} =
+  var a: TLoc = 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 Builder; needsTmp = false) =
+proc genArg(p: BProc, n: PNode, param: PSym; call: PNode; result: var Rope; needsTmp = false) =
  var a: TLoc
  if n.kind == nkStringToCString:
    genArgStringToCString(p, n, result, needsTmp)
  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.returnType) and
+  elif ccgIntroducedPtr(p.config, param, call[0].typ[0]) and 
    (optByRef notin param.options or not p.module.compileToCpp):
    a = initLocExpr(p, n)
    if n.kind in {nkCharLit..nkNilLit}:
-      addAddrLoc(p.config, expressionsNeedsTmp(p, a), result)
+      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:
-    # 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.incl tfVarIsPtr
-    a = initLocExprSingleUse(p, n)
-    a = withTmpIfNeeded(p, a, needsTmp)
-    if needsIndirect: a.flags.incl lfIndirect
+    a = initLocExprSingleUse(p, n[0])
    # 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 != {} and
-        needsIndirect:
+        {lfHeader, lfNoDecl} * callee.sym.loc.flags != {}:
      addAddrLoc(p.config, a, result)
    else:
      addRdLoc(a, result)
  else:
    a = initLocExprSingleUse(p, n)
-    if param.typ.kind in {tyVar, tyPtr, tyRef, tySink}:
-      let typ = skipTypes(param.typ, abstractPtrs)
-      if not sameBackendTypePickyAliases(typ, n.typ.skipTypes(abstractPtrs)):
-        a.snippet = cCast(getTypeDesc(p.module, param.typ), rdCharLoc(a))
    addRdLoc(withTmpIfNeeded(p, a, needsTmp), result)
  #assert result != nil

-proc genArgNoParam(p: BProc, n: PNode; result: var Builder; needsTmp = false) =
+proc genArgNoParam(p: BProc, n: PNode; result: var Rope; needsTmp = false) =
  var a: TLoc
  if n.kind == nkStringToCString:
    genArgStringToCString(p, n, result, needsTmp)
@@ -418,6 +337,35 @@ proc skipTrivialIndirections(n: PNode): PNode =
      result = result[1]
    else: break

+proc getPotentialWrites(n: PNode; mutate: bool; result: var seq[PNode]) =
+  case n.kind:
+  of nkLiterals, nkIdent, nkFormalParams: discard
+  of nkSym:
+    if mutate: result.add n
+  of nkAsgn, nkFastAsgn, nkSinkAsgn:
+    getPotentialWrites(n[0], true, result)
+    getPotentialWrites(n[1], mutate, result)
+  of nkAddr, nkHiddenAddr:
+    getPotentialWrites(n[0], true, result)
+  of nkBracketExpr, nkDotExpr, nkCheckedFieldExpr:
+    getPotentialWrites(n[0], mutate, result)
+  of nkCallKinds:
+    case n.getMagic:
+    of mIncl, mExcl, mInc, mDec, mAppendStrCh, mAppendStrStr, mAppendSeqElem,
+        mAddr, mNew, mNewFinalize, mWasMoved, mDestroy, mReset:
+      getPotentialWrites(n[1], true, result)
+      for i in 2..<n.len:
+        getPotentialWrites(n[i], mutate, result)
+    of mSwap:
+      for i in 1..<n.len:
+        getPotentialWrites(n[i], true, result)
+    else:
+      for i in 1..<n.len:
+        getPotentialWrites(n[i], mutate, result)
+  else:
+    for s in n:
+      getPotentialWrites(s, mutate, result)
+
 proc getPotentialReads(n: PNode; result: var seq[PNode]) =
  case n.kind:
  of nkLiterals, nkIdent, nkFormalParams: discard
@@ -426,7 +374,7 @@ proc getPotentialReads(n: PNode; result: var seq[PNode]) =
    for s in n:
      getPotentialReads(s, result)

-proc genParams(p: BProc, ri: PNode, typ: PType; result: var Builder, argBuilder: var CallBuilder) =
+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)
@@ -442,28 +390,25 @@ proc genParams(p: BProc, ri: PNode, typ: PType; result: var Builder, argBuilder:
        if not needTmp[i - 1]:
          needTmp[i - 1] = potentialAlias(n, potentialWrites)
      getPotentialWrites(ri[i], false, potentialWrites)
-    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
+    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.n.len:
+    if i < typ.len:
      assert(typ.n[i].kind == nkSym)
      let paramType = typ.n[i]
      if not paramType.typ.isCompileTimeOnly:
-        var arg = newBuilder("")
-        genArg(p, ri[i], paramType.sym, ri, arg, needTmp[i-1])
-        if arg.buf.len != 0:
-          result.addArgument(argBuilder):
-            result.add(extract(arg))
+        if oldLen != result.len:
+          result.add(", ")
+          oldLen = result.len
+        genArg(p, ri[i], paramType.sym, ri, result, needTmp[i-1])
    else:
-      var arg = newBuilder("")
-      genArgNoParam(p, ri[i], arg, needTmp[i-1])
-      if arg.buf.len != 0:
-        result.addArgument(argBuilder):
-          result.add(extract(arg))
+      if oldLen != result.len:
+        result.add(", ")
+        oldLen = result.len
+      genArgNoParam(p, ri[i], result, needTmp[i-1])

 proc addActualSuffixForHCR(res: var Rope, module: PSym, sym: PSym) =
  if sym.flags * {sfImportc, sfNonReloadable} == {} and sym.loc.k == locProc and
@@ -472,109 +417,84 @@ proc addActualSuffixForHCR(res: var Rope, module: PSym, sym: PSym) =

 proc genPrefixCall(p: BProc, le, ri: PNode, d: var TLoc) =
  # this is a hotspot in the compiler
-  var op = initLocExpr(p, ri[0])
+  var op: TLoc = 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)

  var callee = rdLoc(op)
  if p.hcrOn and ri[0].kind == nkSym:
    callee.addActualSuffixForHCR(p.module.module, ri[0].sym)
-
-  var res = newBuilder("")
-  var call = initCallBuilder(res, callee)
-  genParams(p, ri, typ, res, call)
-  fixupCall(p, le, ri, d, res, call)
+  fixupCall(p, le, ri, d, callee, params)

 proc genClosureCall(p: BProc, le, ri: PNode, d: var TLoc) =

-  template callProc(rp, params, pTyp: Snippet): Snippet =
-    let e = dotField(rp, "ClE_0")
-    let p = dotField(rp, "ClP_0")
-    let eCall =
-      # note `params` here is actually multiple params
-      if params.len == 0:
-        cCall(p, e)
-      else:
-        cCall(p, params, e)
-    cIfExpr(e,
-      eCall,
-      cCall(cCast(pTyp, p), params))
+  proc addComma(r: Rope): Rope =
+    if r.len == 0: r else: r & ", "

-  template callIter(rp, params: Snippet): Snippet =
-    # we know the env exists
-    let e = dotField(rp, "ClE_0")
-    let p = dotField(rp, "ClP_0")
-    # note `params` here is actually multiple params
-    if params.len == 0:
-      cCall(p, e)
-    else:
-      cCall(p, params, e)
+  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 = initLocExpr(p, ri[0])
+  var op: TLoc = 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 = newBuilder("")
-  var argBuilder = default(CallBuilder) # not initCallBuilder, we just want the params
-  genParams(p, ri, typ, params, argBuilder)
+  var pl = newRopeAppender()
+  genParams(p, ri, typ, pl)

  template genCallPattern {.dirty.} =
-    let rp = rdLoc(op)
-    let pars = extract(params)
-    p.s(cpsStmts).addStmt():
-      if tfIterator in typ.flags:
-        p.s(cpsStmts).add(callIter(rp, pars))
-      else:
-        p.s(cpsStmts).add(callProc(rp, pars, rawProc))
+    if tfIterator in typ.flags:
+      lineF(p, cpsStmts, PatIter & ";$n", [rdLoc(op), pl, pl.addComma, rawProc])
+    else:
+      lineF(p, cpsStmts, PatProc & ";$n", [rdLoc(op), pl, pl.addComma, rawProc])

  let rawProc = getClosureType(p.module, typ, clHalf)
  let canRaise = p.config.exc == excGoto and canRaiseDisp(p, ri[0])
-  if typ.returnType != nil:
+  if typ[0] != 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:
-          d = getTemp(p, typ.returnType, needsInit=true)
+          d = getTemp(p, typ[0], needsInit=true)
        elif d.k notin {locTemp} and not hasNoInit(ri):
          # reset before pass as 'result' var:
          discard "resetLoc(p, d)"
-        params.addArgument(argBuilder):
-          params.add(addrLoc(p.config, d))
+        pl.add(addrLoc(p.config, d))
        genCallPattern()
        if canRaise: raiseExit(p)
      else:
-        var tmp: TLoc = getTemp(p, typ.returnType, needsInit=true)
-        params.addArgument(argBuilder):
-          params.add(addrLoc(p.config, tmp))
+        var tmp: TLoc = getTemp(p, typ[0], 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: d = getTemp(p, typ.returnType)
+      if d.k == locNone: d = getTemp(p, typ[0])
      assert(d.t != nil)        # generate an assignment to d:
      var list: TLoc = initLoc(locCall, d.lode, OnUnknown)
-      let rp = rdLoc(op)
-      let pars = extract(params)
      if tfIterator in typ.flags:
-        list.snippet = callIter(rp, pars)
+        list.r = PatIter % [rdLoc(op), pl, pl.addComma, rawProc]
      else:
-        list.snippet = callProc(rp, pars, rawProc)
+        list.r = 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.returnType)
+      var tmp: TLoc = getTemp(p, typ[0])
      assert(d.t != nil)        # generate an assignment to d:
      var list: TLoc = initLoc(locCall, d.lode, OnUnknown)
-      let rp = rdLoc(op)
-      let pars = extract(params)
      if tfIterator in typ.flags:
-        list.snippet = callIter(rp, pars)
+        list.r = PatIter % [rdLoc(op), pl, pl.addComma, rawProc]
      else:
-        list.snippet = callProc(rp, pars, rawProc)
+        list.r = PatProc % [rdLoc(op), pl, pl.addComma, rawProc]
      genAssignment(p, tmp, list, {})
      if canRaise: raiseExit(p)
      genAssignment(p, d, tmp, {})
@@ -582,27 +502,30 @@ proc genClosureCall(p: BProc, le, ri: PNode, d: var TLoc) =
    genCallPattern()
    if canRaise: raiseExit(p)

-proc genOtherArg(p: BProc; ri: PNode; i: int; typ: PType; result: var Builder;
-                 argBuilder: var CallBuilder) =
-  if i < typ.n.len:
+proc genOtherArg(p: BProc; ri: PNode; i: int; typ: PType; result: var Rope;
+                 argsCounter: var int) =
+  if i < typ.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 paramType.typ.kind in {tyVar} and ri[i].kind == nkHiddenAddr:
-      result.addArgument(argBuilder):
-        genArgNoParam(p, ri[i][0], result)
+    elif typ[i].kind in {tyVar} and ri[i].kind == nkHiddenAddr:
+      if argsCounter > 0: result.add ", "
+      genArgNoParam(p, ri[i][0], result)
+      inc argsCounter
    else:
-      result.addArgument(argBuilder):
-        genArgNoParam(p, ri[i], result) #, typ.n[i].sym)
+      if argsCounter > 0: result.add ", "
+      genArgNoParam(p, ri[i], result) #, typ.n[i].sym)
+      inc argsCounter
  else:
    if tfVarargs notin typ.flags:
      localError(p.config, ri.info, "wrong argument count")
    else:
-      result.addArgument(argBuilder):
-        genArgNoParam(p, ri[i], result)
+      if argsCounter > 0: result.add ", "
+      genArgNoParam(p, ri[i], result)
+      inc argsCounter

 discard """
 Dot call syntax in C++
@@ -659,11 +582,11 @@ proc skipAddrDeref(node: PNode): PNode =
  else:
    result = node

-proc genThisArg(p: BProc; ri: PNode; i: int; typ: PType; result: var Builder) =
+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.n.len
+  internalAssert p.config, i < typ.len
  assert(typ.n[i].kind == nkSym)
  # if the parameter is lying (tyVar) and thus we required an additional deref,
  # skip the deref:
@@ -694,15 +617,15 @@ proc genThisArg(p: BProc; ri: PNode; i: int; typ: PType; result: var Builder) =
    genArgNoParam(p, ri, result) #, typ.n[i].sym)
    result.add(".")

-proc genPatternCall(p: BProc; ri: PNode; pat: string; typ: PType; result: var Builder) =
+proc genPatternCall(p: BProc; ri: PNode; pat: string; typ: PType; result: var Rope) =
  var i = 0
  var j = 1
  while i < pat.len:
    case pat[i]
    of '@':
-      var callBuilder = default(CallBuilder) # not init call builder
+      var argsCounter = 0
      for k in j..<ri.len:
-        genOtherArg(p, ri, k, typ, result, callBuilder)
+        genOtherArg(p, ri, k, typ, result, argsCounter)
      inc i
    of '#':
      if i+1 < pat.len and pat[i+1] in {'+', '@'}:
@@ -712,11 +635,11 @@ proc genPatternCall(p: BProc; ri: PNode; pat: string; typ: PType; result: var Bu
          if pat[i+1] == '+': genArgNoParam(p, ri[0], result)
          result.add("(")
          if 1 < ri.len:
-            var callBuilder: CallBuilder = default(CallBuilder)
-            genOtherArg(p, ri, 1, typ, result, callBuilder)
+            var argsCounterB = 0
+            genOtherArg(p, ri, 1, typ, result, argsCounterB)
          for k in j+1..<ri.len:
-            var callBuilder: CallBuilder = default(CallBuilder)
-            genOtherArg(p, ri, k, typ, result, callBuilder)
+            var argsCounterB = 0
+            genOtherArg(p, ri, k, typ, result, argsCounterB)
          result.add(")")
        else:
          localError(p.config, ri.info, "call expression expected for C++ pattern")
@@ -730,15 +653,15 @@ proc genPatternCall(p: BProc; ri: PNode; pat: string; typ: PType; result: var Bu
        genArgNoParam(p, arg, result)
        #result.add debugTree(arg, 0, 10)
      else:
-        var callBuilder = default(CallBuilder) # not init call builder
-        genOtherArg(p, ri, j, typ, result, callBuilder)
+        var argsCounter = 0
+        genOtherArg(p, ri, j, typ, result, argsCounter)
      inc j
      inc i
    of '\'':
      var idx, stars: int = 0
      if scanCppGenericSlot(pat, i, idx, stars):
        var t = resolveStarsInCppType(typ, idx, stars)
-        if t == nil: result.add(CVoid)
+        if t == nil: result.add("void")
        else: result.add(getTypeDesc(p.module, t))
    else:
      let start = i
@@ -749,61 +672,64 @@ proc genPatternCall(p: BProc; ri: PNode; pat: string; typ: PType; result: var Bu
        result.add(substr(pat, start, i - 1))

 proc genInfixCall(p: BProc, le, ri: PNode, d: var TLoc) =
-  var op = initLocExpr(p, ri[0])
+  var op: TLoc = 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.snippet
+  let pat = $ri[0].sym.loc.r
  internalAssert p.config, pat.len > 0
  if pat.contains({'#', '(', '@', '\''}):
-    var pl = newBuilder("")
+    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.returnType != nil:
+    if typ[0] != 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.snippet = extract(pl)
+        d.r = pl
        excl d.flags, lfSingleUse
      else:
-        if d.k == locNone: d = getTemp(p, typ.returnType)
+        if d.k == locNone: d = getTemp(p, typ[0])
        assert(d.t != nil)        # generate an assignment to d:
        var list: TLoc = initLoc(locCall, d.lode, OnUnknown)
-        list.snippet = extract(pl)
+        list.r = pl
        genAssignment(p, d, list, {}) # no need for deep copying
    else:
-      p.s(cpsStmts).addStmt():
-        p.s(cpsStmts).add(extract(pl))
+      pl.add(";\n")
+      line(p, cpsStmts, pl)
  else:
-    var pl = newBuilder("")
+    var pl = newRopeAppender()
+    var argsCounter = 0
    if 1 < ri.len:
      genThisArg(p, ri, 1, typ, pl)
-    pl.add(op.snippet)
-    var res = newBuilder("")
-    var call = initCallBuilder(res, extract(pl))
+    pl.add(op.r)
+    var params = newRopeAppender()
    for i in 2..<ri.len:
-      genOtherArg(p, ri, i, typ, res, call)
-    fixupCall(p, le, ri, d, res, call)
+      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 = initLocExpr(p, ri[0])
-  var pl = newBuilder("[")
+  var op: TLoc = 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.snippet
+  let pat = $ri[0].sym.loc.r
  internalAssert p.config, pat.len > 0
  var start = 3
  if ' ' in pat:
    start = 1
-    pl.add(op.snippet)
+    pl.add(op.r)
    if ri.len > 1:
      pl.add(": ")
      genArg(p, ri[1], typ.n[1].sym, ri, pl)
@@ -812,12 +738,13 @@ 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.snippet)
+    pl.add(op.r)
    if ri.len > 2:
      pl.add(": ")
      genArg(p, ri[2], typ.n[2].sym, ri, pl)
  for i in start..<ri.len:
-    if i >= typ.n.len:
+    assert(typ.len == typ.n.len)
+    if i >= typ.len:
      internalError(p.config, ri.info, "varargs for objective C method?")
    assert(typ.n[i].kind == nkSym)
    var param = typ.n[i].sym
@@ -825,36 +752,33 @@ 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.returnType != nil:
+  if typ[0] != 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: d = getTemp(p, typ.returnType, needsInit=true)
+        if d.k == locNone: d = getTemp(p, typ[0], needsInit=true)
        pl.add("Result: ")
        pl.add(addrLoc(p.config, d))
-        pl.add("]")
-        p.s(cpsStmts).addStmt():
-          p.s(cpsStmts).add(extract(pl))
+        pl.add("];\n")
+        line(p, cpsStmts, pl)
      else:
-        var tmp: TLoc = getTemp(p, typ.returnType, needsInit=true)
+        var tmp: TLoc = getTemp(p, typ[0], needsInit=true)
        pl.add(addrLoc(p.config, tmp))
-        pl.add("]")
-        p.s(cpsStmts).addStmt():
-          p.s(cpsStmts).add(extract(pl))
+        pl.add("];\n")
+        line(p, cpsStmts, pl)
        genAssignment(p, d, tmp, {}) # no need for deep copying
    else:
      pl.add("]")
-      if d.k == locNone: d = getTemp(p, typ.returnType)
+      if d.k == locNone: d = getTemp(p, typ[0])
      assert(d.t != nil)        # generate an assignment to d:
      var list: TLoc = initLoc(locCall, ri, OnUnknown)
-      list.snippet = extract(pl)
+      list.r = pl
      genAssignment(p, d, list, {}) # no need for deep copying
  else:
-    pl.add("]")
-    p.s(cpsStmts).addStmt():
-      p.s(cpsStmts).add(extract(pl))
+    pl.add("];\n")
+    line(p, cpsStmts, pl)

 proc notYetAlive(n: PNode): bool {.inline.} =
  let r = getRoot(n)
--- a/compiler/ccgexprs.nim
+++ b/compiler/ccgexprs.nim
--- a/compiler/ccgliterals.nim
+++ b/compiler/ccgliterals.nim
@@ -16,10 +16,13 @@
 ## implementation.

 template detectVersion(field, corename) =
-  if m.g.config.selectedGC in {gcArc, gcOrc, gcAtomicArc, gcHooks}:
-    result = 2
-  else:
-    result = 1
+  if m.g.field == 0:
+    let core = getCompilerProc(m.g.graph, corename)
+    if core == nil or core.kind != skConst:
+      m.g.field = 1
+    else:
+      m.g.field = toInt(ast.getInt(core.astdef))
+  result = m.g.field

 proc detectStrVersion(m: BModule): int =
  detectVersion(strVersion, "nimStrVersion")
@@ -33,84 +36,52 @@ proc genStringLiteralDataOnlyV1(m: BModule, s: string; result: var Rope) =
  cgsym(m, "TGenericSeq")
  let tmp = getTempName(m)
  result.add tmp
-  var res = newBuilder("")
-  res.addVarWithTypeAndInitializer(AlwaysConst, name = tmp):
-    res.addSimpleStruct(m, name = "", baseType = ""):
-      res.addField(name = "Sup", typ = "TGenericSeq")
-      res.addArrayField(name = "data", elementType = NimChar, 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.addIntValue(s.len)
-          res.addField(seqInit, name = "reserved"):
-            res.add(cCast(NimInt, cOp(BitOr, NimUint, cCast(NimUint, cIntValue(s.len)), NimStrlitFlag)))
-      res.addField(strInit, name = "data"):
-        res.add(makeCString(s))
-  m.s[cfsStrData].add(extract(res))
+  m.s[cfsStrData].addf("STRING_LITERAL($1, $2, $3);$n",
+       [tmp, makeCString(s), rope(s.len)])

-proc genStringLiteralV1(m: BModule; n: PNode; result: var Builder) =
+proc genStringLiteralV1(m: BModule; n: PNode; result: var Rope) =
  if s.isNil:
-    result.add(cCast(ptrType(cgsymValue(m, "NimStringDesc")), NimNil))
+    appcg(m, result, "((#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:
-      genStringLiteralDataOnlyV1(m, n.strVal, name)
+      appcg(m, result, "((#NimStringDesc*) &", [])
+      genStringLiteralDataOnlyV1(m, n.strVal, result)
+      result.add ")"
    else:
-      name = m.tmpBase & $id
-    result.add(cCast(ptrType(cgsymValue(m, "NimStringDesc")), cAddr(name)))
+      appcg(m, result, "((#NimStringDesc*) &$1$2)",
+                      [m.tmpBase, id])

 # ------ Version 2: destructor based strings and seqs -----------------------

 proc genStringLiteralDataOnlyV2(m: BModule, s: string; result: Rope; isConst: bool) =
-  var res = newBuilder("")
-  res.addVarWithTypeAndInitializer(
-      if isConst: AlwaysConst else: Global,
-      name = result):
-    res.addSimpleStruct(m, name = "", baseType = ""):
-      res.addField(name = "cap", typ = NimInt)
-      res.addArrayField(name = "data", elementType = NimChar, len = s.len + 1)
-  do:
-    var structInit: StructInitializer
-    res.addStructInitializer(structInit, kind = siOrderedStruct):
-      res.addField(structInit, name = "cap"):
-        res.add(cOp(BitOr, NimInt, cIntValue(s.len), NimStrlitFlag))
-      res.addField(structInit, name = "data"):
-        res.add(makeCString(s))
-  m.s[cfsStrData].add(extract(res))
+  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: "")])

-proc genStringLiteralV2(m: BModule; n: PNode; isConst: bool; result: var Builder) =
+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:
-    litName = getTempName(m)
-    genStringLiteralDataOnlyV2(m, n.strVal, litName, isConst)
+    m.s[cfsStrData].addf("static $4 NimStringV2 $1 = {$2, (NimStrPayload*)&$3};$n",
+          [tmp, rope(n.strVal.len), pureLit, rope(if isConst: "const" else: "")])
  else:
-    litName = m.tmpBase & $id
-  let tmp = getTempName(m)
-  result.add tmp
-  var res = newBuilder("")
-  res.addVarWithInitializer(
-      if isConst: AlwaysConst else: Global,
-      name = tmp,
-      typ = "NimStringV2"):
-    var strInit: StructInitializer
-    res.addStructInitializer(strInit, kind = siOrderedStruct):
-      res.addField(strInit, name = "len"):
-        res.addIntValue(n.strVal.len)
-      res.addField(strInit, name = "p"):
-        res.add(cCast(ptrType("NimStrPayload"), cAddr(litName)))
-  m.s[cfsStrData].add(extract(res))
+    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: "")])

-proc genStringLiteralV2Const(m: BModule; n: PNode; isConst: bool; result: var Builder) =
+proc genStringLiteralV2Const(m: BModule; n: PNode; isConst: bool; result: var Rope) =
  let id = nodeTableTestOrSet(m.dataCache, n, m.labels)
  var pureLit: Rope
  if id == m.labels:
@@ -121,12 +92,7 @@ proc genStringLiteralV2Const(m: BModule; n: PNode; isConst: bool; result: var Bu
    genStringLiteralDataOnlyV2(m, n.strVal, pureLit, isConst)
  else:
    pureLit = m.tmpBase & rope(id)
-  var strInit: StructInitializer
-  result.addStructInitializer(strInit, kind = siOrderedStruct):
-    result.addField(strInit, name = "len"):
-      result.addIntValue(n.strVal.len)
-    result.addField(strInit, name = "p"):
-      result.add(cCast(ptrType("NimStrPayload"), cAddr(pureLit)))
+  result.addf "{$1, (NimStrPayload*)&$2}", [rope(n.strVal.len), pureLit]

 # ------ Version selector ---------------------------------------------------

@@ -141,10 +107,10 @@ proc genStringLiteralDataOnly(m: BModule; s: string; info: TLineInfo;
  else:
    localError(m.config, info, "cannot determine how to produce code for string literal")

-proc genNilStringLiteral(m: BModule; info: TLineInfo; result: var Builder) =
-  result.add(cCast(ptrType(cgsymValue(m, "NimStringDesc")), NimNil))
+proc genNilStringLiteral(m: BModule; info: TLineInfo; result: var Rope) =
+  appcg(m, result, "((#NimStringDesc*) NIM_NIL)", [])

-proc genStringLiteral(m: BModule; n: PNode; result: var Builder) =
+proc genStringLiteral(m: BModule; n: PNode; result: var Rope) =
  case detectStrVersion(m)
  of 0, 1: genStringLiteralV1(m, n, result)
  of 2: genStringLiteralV2(m, n, isConst = true, result)
--- a/compiler/ccgreset.nim
+++ b/compiler/ccgreset.nim
@@ -24,31 +24,28 @@ 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.snippet == "": fillObjectFields(p.module, typ)
+    if disc.loc.r == "": fillObjectFields(p.module, typ)
    if disc.loc.t == nil:
      internalError(p.config, n.info, "specializeResetN()")
-    let discField = dotField(accessor, disc.loc.snippet)
-    p.s(cpsStmts).addSwitchStmt(discField):
-      for i in 1..<n.len:
-        let branch = n[i]
-        assert branch.kind in {nkOfBranch, nkElse}
-        var caseBuilder: SwitchCaseBuilder
-        p.s(cpsStmts).addSwitchCase(caseBuilder):
-          if branch.kind == nkOfBranch:
-            genCaseRange(p, branch, caseBuilder)
-          else:
-            p.s(cpsStmts).addCaseElse(caseBuilder)
-        do:
-          specializeResetN(p, accessor, lastSon(branch), typ)
-          p.s(cpsStmts).addBreak()
-    specializeResetT(p, discField, disc.loc.t)
+    lineF(p, cpsStmts, "switch ($1.$2) {$n", [accessor, disc.loc.r])
+    for i in 1..<n.len:
+      let branch = n[i]
+      assert branch.kind in {nkOfBranch, nkElse}
+      if branch.kind == nkOfBranch:
+        genCaseRange(p, branch)
+      else:
+        lineF(p, cpsStmts, "default:$n", [])
+      specializeResetN(p, accessor, lastSon(branch), typ)
+      lineF(p, cpsStmts, "break;$n", [])
+    lineF(p, cpsStmts, "} $n", [])
+    specializeResetT(p, "$1.$2" % [accessor, disc.loc.r], disc.loc.t)
  of nkSym:
    let field = n.sym
    if field.typ.kind == tyVoid: return
-    if field.loc.snippet == "": fillObjectFields(p.module, typ)
+    if field.loc.r == "": fillObjectFields(p.module, typ)
    if field.loc.t == nil:
      internalError(p.config, n.info, "specializeResetN()")
-    specializeResetT(p, dotField(accessor, field.loc.snippet), field.loc.t)
+    specializeResetT(p, "$1.$2" % [accessor, field.loc.r], field.loc.t)
  else: internalError(p.config, n.info, "specializeResetN()")

 proc specializeResetT(p: BProc, accessor: Rope, typ: PType) =
@@ -57,60 +54,50 @@ proc specializeResetT(p: BProc, accessor: Rope, typ: PType) =
  case typ.kind
  of tyGenericInst, tyGenericBody, tyTypeDesc, tyAlias, tyDistinct, tyInferred,
     tySink, tyOwned:
-    specializeResetT(p, accessor, skipModifier(typ))
+    specializeResetT(p, accessor, lastSon(typ))
  of tyArray:
-    let arraySize = lengthOrd(p.config, typ.indexType)
+    let arraySize = lengthOrd(p.config, typ[0])
    var i: TLoc = getTemp(p, getSysType(p.module.g.graph, unknownLineInfo, tyInt))
-    p.s(cpsStmts).addForRangeExclusive(i.snippet, cIntValue(0), cIntValue(arraySize)):
-      specializeResetT(p, subscript(accessor, i.snippet), typ.elementType)
+    linefmt(p, cpsStmts, "for ($1 = 0; $1 < $2; $1++) {$n",
+            [i.r, arraySize])
+    specializeResetT(p, ropecg(p.module, "$1[$2]", [accessor, i.r]), typ[1])
+    lineF(p, cpsStmts, "}$n", [])
  of tyObject:
-    var x = typ.baseClass
-    if x != nil: x = x.skipTypes(skipPtrs)
-    specializeResetT(p, accessor.parentObj(p.module), x)
-    if typ.n != nil:
-      if typ.sym != nil and sfImportc in typ.sym.flags:
-        # imported C struct, nimZeroMem
-        p.s(cpsStmts).addCallStmt(cgsymValue(p.module, "nimZeroMem"),
-          cCast(ptrType(CPointer), cAddr(accessor)),
-          cSizeof(getTypeDesc(p.module, typ)))
-      else:
-        specializeResetN(p, accessor, typ.n, typ)
+    for i in 0..<typ.len:
+      var x = typ[i]
+      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, a in typ.ikids:
-      specializeResetT(p, dotField(accessor, "Field" & $i), a)
+    for i in 0..<typ.len:
+      specializeResetT(p, ropecg(p.module, "$1.Field$2", [accessor, i]), typ[i])

  of tyString, tyRef, tySequence:
-    p.s(cpsStmts).addCallStmt(cgsymValue(p.module, "unsureAsgnRef"),
-      cCast(ptrType(CPointer), cAddr(accessor)),
-      NimNil)
+    lineCg(p, cpsStmts, "#unsureAsgnRef((void**)&$1, NIM_NIL);$n", [accessor])

  of tyProc:
    if typ.callConv == ccClosure:
-      p.s(cpsStmts).addCallStmt(cgsymValue(p.module, "unsureAsgnRef"),
-        cCast(ptrType(CPointer), cAddr(dotField(accessor, "ClE_0"))),
-        NimNil)
-      p.s(cpsStmts).addFieldAssignment(accessor, "ClP_0", NimNil)
+      lineCg(p, cpsStmts, "#unsureAsgnRef((void**)&$1.ClE_0, NIM_NIL);$n", [accessor])
+      lineCg(p, cpsStmts, "$1.ClP_0 = NIM_NIL;$n", [accessor])
    else:
-      p.s(cpsStmts).addAssignment(accessor, NimNil)
-  of tyChar, tyBool, tyEnum, tyRange, tyInt..tyUInt64:
-    p.s(cpsStmts).addAssignment(accessor, cIntValue(0))
+      lineCg(p, cpsStmts, "$1 = NIM_NIL;$n", [accessor])
+  of tyChar, tyBool, tyEnum, tyInt..tyUInt64:
+    lineCg(p, cpsStmts, "$1 = 0;$n", [accessor])
  of tyCstring, tyPointer, tyPtr, tyVar, tyLent:
-    p.s(cpsStmts).addAssignment(accessor, NimNil)
+    lineCg(p, cpsStmts, "$1 = NIM_NIL;$n", [accessor])
  of tySet:
    case mapSetType(p.config, typ)
    of ctArray:
-      let t = getTypeDesc(p.module, typ)
-      p.s(cpsStmts).addCallStmt(cgsymValue(p.module, "nimZeroMem"),
-        accessor,
-        cSizeof(t))
+      lineCg(p, cpsStmts, "#nimZeroMem($1, sizeof($2));$n",
+          [accessor, getTypeDesc(p.module, typ)])
    of ctInt8, ctInt16, ctInt32, ctInt64:
-      p.s(cpsStmts).addAssignment(accessor, cIntValue(0))
+      lineCg(p, cpsStmts, "$1 = 0;$n", [accessor])
    else:
      raiseAssert "unexpected set type kind"
  of tyNone, tyEmpty, tyNil, tyUntyped, tyTyped, tyGenericInvocation,
-      tyGenericParam, tyOrdinal, tyOpenArray, tyForward, tyVarargs,
-      tyUncheckedArray, tyError, tyBuiltInTypeClass, tyUserTypeClass,
+      tyGenericParam, tyOrdinal, tyRange, tyOpenArray, tyForward, tyVarargs,
+      tyUncheckedArray, tyProxy, tyBuiltInTypeClass, tyUserTypeClass,
      tyUserTypeClassInst, tyCompositeTypeClass, tyAnd, tyOr, tyNot,
      tyAnything, tyStatic, tyFromExpr, tyConcept, tyVoid, tyIterable:
    discard
--- a/compiler/ccgstmts.nim
+++ b/compiler/ccgstmts.nim
--- a/compiler/ccgthreadvars.nim
+++ b/compiler/ccgthreadvars.nim
@@ -19,12 +19,9 @@ proc accessThreadLocalVar(p: BProc, s: PSym) =
  if emulatedThreadVars(p.config) and threadVarAccessed notin p.flags:
    p.flags.incl threadVarAccessed
    incl p.module.flags, usesThreadVars
-    p.procSec(cpsLocals).addVar(kind = Local,
-      name = "NimTV_",
-      typ = ptrType("NimThreadVars"))
-    p.procSec(cpsInit).addAssignment("NimTV_",
-      cCast(ptrType("NimThreadVars"),
-        cCall(cgsymValue(p.module, "GetThreadLocalVars"))))
+    p.procSec(cpsLocals).addf("\tNimThreadVars* NimTV_;$n", [])
+    p.procSec(cpsInit).add(
+      ropecg(p.module, "\tNimTV_ = (NimThreadVars*) #GetThreadLocalVars();$n", []))

 proc declareThreadVar(m: BModule, s: PSym, isExtern: bool) =
  if emulatedThreadVars(m.config):
@@ -33,32 +30,30 @@ 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.addField(name = s.loc.snippet, typ = getTypeDesc(m, s.loc.t))
+      m.g.nimtv.addf("$1 $2;$n", [getTypeDesc(m, s.loc.t), s.loc.r])
  else:
-    let vis =
-      if isExtern: Extern
-      elif lfExportLib in s.loc.flags: ExportLibVar
-      else: Private
-    m.s[cfsVars].addVar(m, s,
-      name = s.loc.snippet,
-      typ = getTypeDesc(m, s.loc.t),
-      kind = Threadvar,
-      visibility = vis)
+    if isExtern: m.s[cfsVars].add("extern ")
+    elif lfExportLib in s.loc.flags: m.s[cfsVars].add("N_LIB_EXPORT_VAR ")
+    else: m.s[cfsVars].add("N_LIB_PRIVATE ")
+    if optThreads in m.config.globalOptions:
+      let sym = s.typ.sym
+      if sym != nil and sfCppNonPod in sym.flags:
+        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])

 proc generateThreadLocalStorage(m: BModule) =
-  if m.g.nimtv.buf.len != 0 and (usesThreadVars in m.flags or sfMainModule in m.module.flags):
+  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].addTypedef(name = "NimThreadVars"):
-      m.s[cfsSeqTypes].addSimpleStruct(m, name = "", baseType = ""):
-        m.s[cfsSeqTypes].add(extract(m.g.nimtv))
+    m.s[cfsSeqTypes].addf("typedef struct {$1} NimThreadVars;$n", [m.g.nimtv])

 proc generateThreadVarsSize(m: BModule) =
-  if m.g.nimtv.buf.len != 0:
+  if m.g.nimtv != "":
    let externc = if m.config.backend == backendCpp or
-                       sfCompileToCpp in m.module.flags: ExternC
-                  else: None
-    m.s[cfsProcs].addDeclWithVisibility(externc):
-      m.s[cfsProcs].addProcHeader("NimThreadVarsSize", NimInt, cProcParams())
-      m.s[cfsProcs].finishProcHeaderWithBody():
-        m.s[cfsProcs].addReturn(cCast(NimInt, cSizeof("NimThreadVars")))
+                       sfCompileToCpp in m.module.flags: "extern \"C\" "
+                  else: ""
+    m.s[cfsProcs].addf(
+      "$#NI NimThreadVarsSize(){return (NI)sizeof(NimThreadVars);}$n",
+      [externc.rope])
--- a/compiler/ccgtrav.nim
+++ b/compiler/ccgtrav.nim
@@ -16,16 +16,13 @@ type
    p: BProc
    visitorFrmt: string

+const
+  visitorFrmt = "#nimGCvisit((void*)$1, $2);$n"

 proc genTraverseProc(c: TTraversalClosure, accessor: Rope, typ: PType)
-proc genCaseRange(p: BProc, branch: PNode, info: var SwitchCaseBuilder)
+proc genCaseRange(p: BProc, branch: PNode)
 proc getTemp(p: BProc, t: PType, needsInit=false): TLoc

-proc visit(p: BProc, data, visitor: Snippet) =
-  p.s(cpsStmts).addCallStmt(cgsymValue(p.module, "nimGCvisit"),
-    cCast(CPointer, data),
-    visitor)
-
 proc genTraverseProc(c: TTraversalClosure, accessor: Rope, n: PNode;
                     typ: PType) =
  if n == nil: return
@@ -37,35 +34,32 @@ 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.snippet == "": fillObjectFields(c.p.module, typ)
+    if disc.loc.r == "": fillObjectFields(c.p.module, typ)
    if disc.loc.t == nil:
      internalError(c.p.config, n.info, "genTraverseProc()")
-    let discField = dotField(accessor, disc.loc.snippet)
-    p.s(cpsStmts).addSwitchStmt(discField):
-      for i in 1..<n.len:
-        let branch = n[i]
-        assert branch.kind in {nkOfBranch, nkElse}
-        var caseBuilder: SwitchCaseBuilder
-        p.s(cpsStmts).addSwitchCase(caseBuilder):
-          if branch.kind == nkOfBranch:
-            genCaseRange(c.p, branch, caseBuilder)
-          else:
-            p.s(cpsStmts).addCaseElse(caseBuilder)
-        do:
-          genTraverseProc(c, accessor, lastSon(branch), typ)
-          p.s(cpsStmts).addBreak()
+    lineF(p, cpsStmts, "switch ($1.$2) {$n", [accessor, disc.loc.r])
+    for i in 1..<n.len:
+      let branch = n[i]
+      assert branch.kind in {nkOfBranch, nkElse}
+      if branch.kind == nkOfBranch:
+        genCaseRange(c.p, branch)
+      else:
+        lineF(p, cpsStmts, "default:$n", [])
+      genTraverseProc(c, accessor, lastSon(branch), typ)
+      lineF(p, cpsStmts, "break;$n", [])
+    lineF(p, cpsStmts, "} $n", [])
  of nkSym:
    let field = n.sym
    if field.typ.kind == tyVoid: return
-    if field.loc.snippet == "": fillObjectFields(c.p.module, typ)
+    if field.loc.r == "": fillObjectFields(c.p.module, typ)
    if field.loc.t == nil:
      internalError(c.p.config, n.info, "genTraverseProc()")
-    genTraverseProc(c, dotField(accessor, field.loc.snippet), field.loc.t)
+    genTraverseProc(c, "$1.$2" % [accessor, field.loc.r], field.loc.t)
  else: internalError(c.p.config, n.info, "genTraverseProc()")

 proc parentObj(accessor: Rope; m: BModule): Rope {.inline.} =
  if not m.compileToCpp:
-    result = dotField(accessor, "Sup")
+    result = "$1.Sup" % [accessor]
  else:
    result = accessor

@@ -77,156 +71,125 @@ proc genTraverseProc(c: TTraversalClosure, accessor: Rope, typ: PType) =
  case typ.kind
  of tyGenericInst, tyGenericBody, tyTypeDesc, tyAlias, tyDistinct, tyInferred,
     tySink, tyOwned:
-    genTraverseProc(c, accessor, skipModifier(typ))
+    genTraverseProc(c, accessor, lastSon(typ))
  of tyArray:
-    let arraySize = lengthOrd(c.p.config, typ.indexType)
+    let arraySize = lengthOrd(c.p.config, typ[0])
    var i: TLoc = getTemp(p, getSysType(c.p.module.g.graph, unknownLineInfo, tyInt))
    var oldCode = p.s(cpsStmts)
-    var oldLen, newLen: int
-    p.s(cpsStmts).addForRangeExclusive(i.snippet, cIntValue(0), cIntValue(arraySize)):
-      oldLen = p.s(cpsStmts).buf.len
-      genTraverseProc(c, subscript(accessor, i.snippet), typ.elementType)
-      newLen = p.s(cpsStmts).buf.len
-    if oldLen == newLen:
+    freeze oldCode
+    linefmt(p, cpsStmts, "for ($1 = 0; $1 < $2; $1++) {$n",
+            [i.r, arraySize])
+    let oldLen = p.s(cpsStmts).len
+    genTraverseProc(c, ropecg(c.p.module, "$1[$2]", [accessor, i.r]), typ[1])
+    if p.s(cpsStmts).len == oldLen:
      # do not emit dummy long loops for faster debug builds:
      p.s(cpsStmts) = oldCode
+    else:
+      lineF(p, cpsStmts, "}$n", [])
  of tyObject:
-    var x = typ.baseClass
-    if x != nil: x = x.skipTypes(skipPtrs)
-    genTraverseProc(c, accessor.parentObj(c.p.module), x)
+    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)
    if typ.n != nil: genTraverseProc(c, accessor, typ.n, typ)
  of tyTuple:
    let typ = getUniqueType(typ)
-    for i, a in typ.ikids:
-      genTraverseProc(c, dotField(accessor, "Field" & $i), a)
+    for i in 0..<typ.len:
+      genTraverseProc(c, ropecg(c.p.module, "$1.Field$2", [accessor, i]), typ[i])
  of tyRef:
-    visit(p, accessor, c.visitorFrmt)
+    lineCg(p, cpsStmts, visitorFrmt, [accessor, c.visitorFrmt])
  of tySequence:
    if optSeqDestructors notin c.p.module.config.globalOptions:
-      visit(p, accessor, c.visitorFrmt)
-    elif containsGarbageCollectedRef(typ.elementType):
+      lineCg(p, cpsStmts, visitorFrmt, [accessor, c.visitorFrmt])
+    elif containsGarbageCollectedRef(typ.lastSon):
      # destructor based seqs are themselves not traced but their data is, if
      # they contain a GC'ed type:
-      p.s(cpsStmts).addCallStmt(cgsymValue(p.module, "nimGCvisitSeq"),
-        cCast(CPointer, accessor),
-        c.visitorFrmt)
+      lineCg(p, cpsStmts, "#nimGCvisitSeq((void*)$1, $2);$n", [accessor, c.visitorFrmt])
      #genTraverseProcSeq(c, accessor, typ)
  of tyString:
    if tfHasAsgn notin typ.flags:
-      visit(p, accessor, c.visitorFrmt)
+      lineCg(p, cpsStmts, visitorFrmt, [accessor, c.visitorFrmt])
  of tyProc:
    if typ.callConv == ccClosure:
-      visit(p, dotField(accessor, "ClE_0"), c.visitorFrmt)
+      lineCg(p, cpsStmts, visitorFrmt, [ropecg(c.p.module, "$1.ClE_0", [accessor]), c.visitorFrmt])
  else:
    discard

 proc genTraverseProcSeq(c: TTraversalClosure, accessor: Rope, typ: PType) =
  var p = c.p
  assert typ.kind == tySequence
-  var i = getTemp(p, getSysType(c.p.module.g.graph, unknownLineInfo, tyInt))
+  var i: TLoc = getTemp(p, getSysType(c.p.module.g.graph, unknownLineInfo, tyInt))
  var oldCode = p.s(cpsStmts)
-  var oldLen, newLen: int
-  var a = TLoc(snippet: accessor)
-  let le = lenExpr(c.p, a)
+  freeze oldCode
+  var a: TLoc = TLoc(r: accessor)

-  p.s(cpsStmts).addForRangeExclusive(i.snippet, cIntValue(0), le):
-    oldLen = p.s(cpsStmts).buf.len
-    genTraverseProc(c, subscript(dataField(c.p, accessor), i.snippet), typ.elementType)
-    newLen = p.s(cpsStmts).buf.len
-  if newLen == oldLen:
+  lineF(p, cpsStmts, "for ($1 = 0; $1 < $2; $1++) {$n",
+      [i.r, lenExpr(c.p, a)])
+  let oldLen = p.s(cpsStmts).len
+  genTraverseProc(c, "$1$3[$2]" % [accessor, i.r, dataField(c.p)], typ[0])
+  if p.s(cpsStmts).len == oldLen:
    # do not emit dummy long loops for faster debug builds:
    p.s(cpsStmts) = oldCode
+  else:
+    lineF(p, cpsStmts, "}$n", [])

 proc genTraverseProc(m: BModule, origTyp: PType; sig: SigHash): Rope =
+  var c: TTraversalClosure
  var p = newProc(nil, m)
  result = "Marker_" & getTypeName(m, origTyp, sig)
  let
    hcrOn = m.hcrOn
    typ = origTyp.skipTypes(abstractInstOwned)
    markerName = if hcrOn: result & "_actual" else: result
+    header = "static N_NIMCALL(void, $1)(void* p, NI op)" % [markerName]
    t = getTypeDesc(m, typ)

-  p.s(cpsLocals).addVar(kind = Local, name = "a", typ = t)
-  p.s(cpsInit).addAssignment("a", cCast(t, "p"))
+  lineF(p, cpsLocals, "$1 a;$n", [t])
+  lineF(p, cpsInit, "a = ($1)p;$n", [t])

-  var c = TTraversalClosure(p: p,
-    visitorFrmt: "op" # "#nimGCvisit((void*)$1, op);$n"
-    )
+  c.p = p
+  c.visitorFrmt = "op" # "#nimGCvisit((void*)$1, op);$n"

  assert typ.kind != tyTypeDesc
  if typ.kind == tySequence:
    genTraverseProcSeq(c, "a".rope, typ)
  else:
-    if skipTypes(typ.elementType, typedescInst+{tyOwned}).kind == tyArray:
+    if skipTypes(typ[0], typedescInst+{tyOwned}).kind == tyArray:
      # C's arrays are broken beyond repair:
-      genTraverseProc(c, "a".rope, typ.elementType)
+      genTraverseProc(c, "a".rope, typ[0])
    else:
-      genTraverseProc(c, cDeref("a"), typ.elementType)
+      genTraverseProc(c, "(*a)".rope, typ[0])

-  var headerBuilder = newBuilder("")
-  headerBuilder.addProcHeaderWithParams(ccNimCall, markerName, CVoid):
-    var paramBuilder: ProcParamBuilder
-    headerBuilder.addProcParams(paramBuilder):
-      headerBuilder.addParam(paramBuilder, name = "p", typ = CPointer)
-      headerBuilder.addParam(paramBuilder, name = "op", typ = NimInt)
-  let header = extract(headerBuilder)
+  let generatedProc = "$1 {$n$2$3$4}\n" %
+        [header, p.s(cpsLocals), p.s(cpsInit), p.s(cpsStmts)]

-  m.s[cfsProcHeaders].addDeclWithVisibility(StaticProc):
-    m.s[cfsProcHeaders].add(header)
-    m.s[cfsProcHeaders].finishProcHeaderAsProto()
-  m.s[cfsProcs].addDeclWithVisibility(StaticProc):
-    m.s[cfsProcs].add(header)
-    m.s[cfsProcs].finishProcHeaderWithBody():
-      m.s[cfsProcs].add(extract(p.s(cpsLocals)))
-      m.s[cfsProcs].add(extract(p.s(cpsInit)))
-      m.s[cfsProcs].add(extract(p.s(cpsStmts)))
+  m.s[cfsProcHeaders].addf("$1;\n", [header])
+  m.s[cfsProcs].add(generatedProc)

  if hcrOn:
-    var desc = newBuilder("")
-    var unnamedParamBuilder: ProcParamBuilder
-    desc.addProcParams(unnamedParamBuilder):
-      desc.addUnnamedParam(unnamedParamBuilder, CPointer)
-      desc.addUnnamedParam(unnamedParamBuilder, NimInt)
-    let unnamedParams = extract(desc)
-    m.s[cfsProcHeaders].addProcVar(ccNimCall, result, unnamedParams, CVoid)
-    m.s[cfsDynLibInit].addAssignmentWithValue(result):
-      m.s[cfsDynLibInit].addCast(procPtrTypeUnnamed(ccNimCall, CVoid, unnamedParams)):
-        m.s[cfsDynLibInit].addCall("hcrRegisterProc",
-          getModuleDllPath(m),
-          '"' & result & '"',
-          cCast(CPointer, markerName))
+    m.s[cfsProcHeaders].addf("N_NIMCALL_PTR(void, $1)(void*, NI);\n", [result])
+    m.s[cfsDynLibInit].addf("\t$1 = (N_NIMCALL_PTR(void, )(void*, NI)) hcrRegisterProc($3, \"$1\", (void*)$2);\n",
+         [result, markerName, getModuleDllPath(m)])

 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)

  if sfThread in s.flags and emulatedThreadVars(m.config):
    accessThreadLocalVar(p, s)
-    sLoc = derefField("NimTV_", sLoc)
-
-  var c = TTraversalClosure(p: p,
-    visitorFrmt: cIntValue(0) # "#nimGCvisit((void*)$1, 0);$n"
-  )
+    sLoc = "NimTV_->" & sLoc

+  c.visitorFrmt = "0" # "#nimGCvisit((void*)$1, 0);$n"
+  c.p = p
+  let header = "static N_NIMCALL(void, $1)(void)" % [result]
  genTraverseProc(c, sLoc, s.loc.t)

-  var headerBuilder = newBuilder("")
-  headerBuilder.addProcHeaderWithParams(ccNimCall, result, CVoid):
-    var paramBuilder: ProcParamBuilder
-    headerBuilder.addProcParams(paramBuilder):
-      # (void)
-      discard
-  let header = extract(headerBuilder)
+  let generatedProc = "$1 {$n$2$3$4}$n" %
+        [header, p.s(cpsLocals), p.s(cpsInit), p.s(cpsStmts)]

-  m.s[cfsProcHeaders].addDeclWithVisibility(StaticProc):
-    m.s[cfsProcHeaders].add(header)
-    m.s[cfsProcHeaders].finishProcHeaderAsProto()
-  m.s[cfsProcs].addDeclWithVisibility(StaticProc):
-    m.s[cfsProcs].add(header)
-    m.s[cfsProcs].finishProcHeaderWithBody():
-      m.s[cfsProcs].add(extract(p.s(cpsLocals)))
-      m.s[cfsProcs].add(extract(p.s(cpsInit)))
-      m.s[cfsProcs].add(extract(p.s(cpsStmts)))
+  m.s[cfsProcHeaders].addf("$1;$n", [header])
+  m.s[cfsProcs].add(generatedProc)
--- a/compiler/ccgtypes.nim
+++ b/compiler/ccgtypes.nim
--- a/compiler/ccgutils.nim
+++ b/compiler/ccgutils.nim
@@ -10,10 +10,8 @@
 # This module declares some helpers for the C code generator.

 import
-  ast, types, msgs, wordrecg,
-  platform, trees, options, cgendata, mangleutils, renderer
-
-import std/[hashes, strutils, formatfloat]
+  ast, types, hashes, strutils, msgs, wordrecg,
+  platform, trees, options, cgendata

 when defined(nimPreviewSlimSystem):
  import std/assertions
@@ -68,6 +66,53 @@ 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
@@ -79,10 +124,10 @@ proc mapSetType(conf: ConfigRef; typ: PType): TCTypeKind =
 proc ccgIntroducedPtr*(conf: ConfigRef; s: PSym, retType: PType): bool =
  var pt = skipTypes(s.typ, typedescInst)
  assert skResult != s.kind
-
+  
  #note precedence: params override types
  if optByRef in s.options: return true
-  elif sfByCopy in s.flags: return false
+  elif sfByCopy in s.flags: return false 
  elif tfByRef in pt.flags: return true
  elif tfByCopy in pt.flags: return false
  case pt.kind
@@ -106,67 +151,3 @@ proc ccgIntroducedPtr*(conf: ConfigRef; s: PSym, retType: PType): bool =
    result = not (pt.kind in {tyVar, tyArray, tyOpenArray, tyVarargs, tyRef, tyPtr, tyPointer} or
      pt.kind == tySet and mapSetType(conf, pt) == ctArray)

-proc encodeName*(name: string): string =
-  result = mangle(name)
-  result = $result.len & result
-
-proc makeUnique(m: BModule; s: PSym, name: string = ""): string =
-  result = if name == "": s.name.s else: name
-  result.add "__"
-  result.add m.g.graph.ifaces[s.itemId.module].uniqueName
-  result.add "_u"
-  result.add $s.itemId.item
-
-proc encodeSym*(m: BModule; s: PSym; makeUnique: bool = false; extra: string = ""): string =
-  #Module::Type
-  var name = s.name.s & extra
-  if makeUnique:
-    name = makeUnique(m, s, name)
-  "N" & encodeName(s.skipGenericOwner.name.s) & encodeName(name) & "E"
-
-proc encodeType*(m: BModule; t: PType; staticLists: var string): string =
-  result = ""
-  var kindName = ($t.kind)[2..^1]
-  kindName[0] = toLower($kindName[0])[0]
-  case t.kind
-  of tyObject, tyEnum, tyDistinct, tyUserTypeClass, tyGenericParam:
-    result = encodeSym(m, t.sym)
-  of tyGenericInst, tyUserTypeClassInst, tyGenericBody:
-    result = encodeName(t[0].sym.name.s)
-    result.add "I"
-    for i in 1..<t.len - 1:
-      result.add encodeType(m, t[i], staticLists)
-    result.add "E"
-  of tySequence, tyOpenArray, tyArray, tyVarargs, tyTuple, tyProc, tySet, tyTypeDesc,
-    tyPtr, tyRef, tyVar, tyLent, tySink, tyUncheckedArray, tyOr, tyAnd, tyBuiltInTypeClass:
-    result =
-      case t.kind:
-      of tySequence: encodeName("seq")
-      else: encodeName(kindName)
-    result.add "I"
-    for i in 0..<t.len:
-      let s = t[i]
-      if s.isNil: continue
-      result.add encodeType(m, s, staticLists)
-    result.add "E"
-  of tyStatic:
-    if t.n != nil:
-      staticLists.add "_s" & renderTree(t.n)
-    else:
-      raiseAssert "unreachable"
-  of tyRange:
-    var val = "range_"
-    if t.n[0].typ.kind in {tyFloat..tyFloat128}:
-      val.addFloat t.n[0].floatVal
-      val.add "_"
-      val.addFloat t.n[1].floatVal
-    else:
-      val.add $t.n[0].intVal & "_" & $t.n[1].intVal
-    result = encodeName(val)
-  of tyString..tyUInt64, tyPointer, tyBool, tyChar, tyVoid, tyAnything, tyNil, tyEmpty:
-    result = encodeName(kindName)
-  of tyAlias, tyInferred, tyOwned:
-    result = encodeType(m, t.elementType, staticLists)
-  else:
-    assert false, "encodeType " & $t.kind
-
--- a/compiler/cgen.nim
+++ b/compiler/cgen.nim
--- a/compiler/cgendata.nim
+++ b/compiler/cgendata.nim
@@ -10,10 +10,8 @@
 ## This module contains the data structures for the C code generation phase.

 import
-  ast, ropes, options,
-  lineinfos, pathutils, modulegraphs, cbuilderbase
-
-import std/[intsets, tables, sets]
+  ast, ropes, options, intsets,
+  tables, ndi, lineinfos, pathutils, modulegraphs, sets

 type
  TLabel* = Rope              # for the C generator a label is just a rope
@@ -43,12 +41,12 @@ type
    ctUInt, ctUInt8, ctUInt16, ctUInt32, ctUInt64,
    ctArray, ctPtrToArray, ctStruct, ctPtr, ctNimStr, ctNimSeq, ctProc,
    ctCString
-  TCFileSections* = array[TCFileSection, Builder] # represents a generated C file
+  TCFileSections* = array[TCFileSection, Rope] # represents a generated C file
  TCProcSection* = enum       # the sections a generated C proc consists of
    cpsLocals,                # section of local variables for C proc
    cpsInit,                  # section for init of variables for C proc
    cpsStmts                  # section of local statements for C proc
-  TCProcSections* = array[TCProcSection, Builder] # represents a generated C proc
+  TCProcSections* = array[TCProcSection, Rope] # represents a generated C proc
  BModule* = ref TCGen
  BProc* = ref TCProc
  TBlock* = object
@@ -88,7 +86,7 @@ type
    options*: TOptions        # options that should be used for code
                              # generation; this is the same as prc.options
                              # unless prc == nil
-    optionsStack*: seq[(TOptions, TNoteKinds)]
+    optionsStack*: seq[TOptions]
    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
@@ -115,11 +113,11 @@ type
                        # computing alive data on our own.

  BModuleList* = ref object of RootObj
-    mainModProcs*, mainModInit*, otherModsInit*, mainDatInit*: Builder
+    mainModProcs*, mainModInit*, otherModsInit*, mainDatInit*: Rope
    mapping*: Rope             # the generated mapping file (if requested)
-    mods*: seq[BModule]     # list of all compiled modules
+    modules*: seq[BModule]     # list of all compiled modules
    modulesClosed*: seq[BModule] # list of the same compiled modules, but in the order they were closed
-    forwardedProcs*: seq[PSym] # procs that did not yet have a body
+    forwardedProcs*: seq[PSym] # proc:s that did not yet have a body
    generatedHeader*: BModule
    typeInfoMarker*: TypeCacheWithOwner
    typeInfoMarkerV2*: TypeCacheWithOwner
@@ -127,7 +125,7 @@ type
    graph*: ModuleGraph
    strVersion*, seqVersion*: int # version of the string/seq implementation to use

-    nimtv*: Builder         # Nim thread vars; the struct body
+    nimtv*: Rope            # Nim thread vars; the struct body
    nimtvDeps*: seq[PType]  # type deps: every module needs whole struct
    nimtvDeclared*: IntSet  # so that every var/field exists only once
                            # in the struct
@@ -137,7 +135,6 @@ type
                            # unconditionally...
                            # nimtvDeps is VERY hard to cache because it's
                            # not a list of IDs nor can it be made to be one.
-    mangledPrcs*: HashSet[string]

  TCGen = object of PPassContext # represents a C source file
    s*: TCFileSections        # sections of the C file
@@ -151,53 +148,49 @@ type
    typeABICache*: HashSet[SigHash] # cache for ABI checks; reusing typeCache
                              # would be ideal but for some reason enums
                              # don't seem to get cached so it'd generate
-                              # 1 ABI check per occurrence in code
+                              # 1 ABI check per occurence in code
    forwTypeCache*: TypeCache # cache for forward declarations of types
    declaredThings*: IntSet   # things we have declared in this .c file
    declaredProtos*: IntSet   # prototypes we have declared in this .c file
-    queue*: seq[PSym]         # queue of procs to generate
    alive*: IntSet            # symbol IDs of alive data as computed by `dce.nim`
    headerFiles*: seq[string] # needed headers to include
    typeInfoMarker*: TypeCache # needed for generating type information
    typeInfoMarkerV2*: TypeCache
    initProc*: BProc          # code for init procedure
    preInitProc*: BProc       # code executed before the init proc
-    hcrCreateTypeInfosProc*: Builder # type info globals are in here when HCR=on
+    hcrCreateTypeInfosProc*: Rope # type info globals are in here when HCR=on
    inHcrInitGuard*: bool     # We are currently within a HCR reloading guard.
-    hcrInitGuard*: IfBuilder
    typeStack*: TTypeSeq      # used for type generation
    dataCache*: TNodeTable
    typeNodes*, nimTypes*: int # used for type info generation
    typeNodesName*, nimTypesName*: Rope # used for type info generation
    labels*: Natural          # for generating unique module-scope names
-    extensionLoaders*: array['0'..'9', Builder] # special procs for the
+    extensionLoaders*: array['0'..'9', Rope] # special procs for the
                                             # OpenGL wrapper
    sigConflicts*: CountTable[SigHash]
    g*: BModuleList
+    ndi*: NdiFile

 template config*(m: BModule): ConfigRef = m.g.config
 template config*(p: BProc): ConfigRef = p.module.g.config
 template vccAndC*(p: BProc): bool = p.module.config.cCompiler == ccVcc and p.module.config.backend == backendC

-proc delayedCodegen*(m: BModule): bool {.inline.} =
-  useAliveDataFromDce in m.flags or m.config.globalOptions.contains(optCompress)
-
 proc includeHeader*(this: BModule; header: string) =
  if not this.headerFiles.contains header:
    this.headerFiles.add header

-proc s*(p: BProc, s: TCProcSection): var Builder {.inline.} =
+proc s*(p: BProc, s: TCProcSection): var Rope {.inline.} =
  # section in the current block
  result = p.blocks[^1].sections[s]

-proc procSec*(p: BProc, s: TCProcSection): var Builder {.inline.} =
+proc procSec*(p: BProc, s: TCProcSection): var Rope {.inline.} =
  # top level proc sections
  result = p.blocks[0].sections[s]

 proc initBlock*(): TBlock =
  result = TBlock()
  for i in low(result.sections)..high(result.sections):
-    result.sections[i] = newBuilder("")
+    result.sections[i] = newRopeAppender()

 proc newProc*(prc: PSym, module: BModule): BProc =
  result = BProc(
--- a/compiler/cgmeth.nim
+++ b/compiler/cgmeth.nim
@@ -10,15 +10,12 @@
 ## This module implements code generation for methods.

 import
-  options, ast, msgs, idents, renderer, types, magicsys,
-  sempass2, modulegraphs, lineinfos, astalgo
-
-import std/intsets
+  intsets, options, ast, msgs, idents, renderer, types, magicsys,
+  sempass2, modulegraphs, lineinfos

 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)
@@ -69,23 +66,21 @@ type
 proc sameMethodBucket(a, b: PSym; multiMethods: bool): MethodResult =
  result = No
  if a.name.id != b.name.id: return
-  if a.typ.signatureLen != b.typ.signatureLen:
+  if a.typ.len != b.typ.len:
    return

-  var i = 0
-  for x, y in paramTypePairs(a.typ, b.typ):
-    inc i
-    var aa = x
-    var bb = y
+  for i in 1..<a.typ.len:
+    var aa = a.typ[i]
+    var bb = b.typ[i]
    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.elementType
-        bb = bb.elementType
+        aa = aa.lastSon
+        bb = bb.lastSon
      else:
        break
-    if sameType(x, y):
+    if sameType(a.typ[i], b.typ[i]):
      if aa.kind == tyObject and result != Invalid:
        result = Yes
    elif aa.kind == tyObject and bb.kind == tyObject and (i == 1 or multiMethods):
@@ -103,11 +98,10 @@ proc sameMethodBucket(a, b: PSym; multiMethods: bool): MethodResult =
      return No
  if result == Yes:
    # check for return type:
-    # ignore flags of return types; # bug #22673
-    if not sameTypeOrNil(a.typ.returnType, b.typ.returnType, {IgnoreFlags}):
-      if b.typ.returnType != nil and b.typ.returnType.kind == tyUntyped:
+    if not sameTypeOrNil(a.typ[0], b.typ[0]):
+      if b.typ[0] != nil and b.typ[0].kind == tyUntyped:
        # infer 'auto' from the base to make it consistent:
-        b.typ.setReturnType a.typ.returnType
+        b.typ[0] = a.typ[0]
      else:
        return No

@@ -123,18 +117,18 @@ proc attachDispatcher(s: PSym, dispatcher: PNode) =

 proc createDispatcher(s: PSym; g: ModuleGraph; idgen: IdGenerator): PSym =
  var disp = copySym(s, idgen)
-  incl(disp, sfDispatcher)
-  excl(disp, sfExported)
+  incl(disp.flags, sfDispatcher)
+  excl(disp.flags, sfExported)
  let old = disp.typ
-  disp.typ = copyType(disp.typ, idgen, disp.typ.owner)
+  disp.typ = copyType(disp.typ, nextTypeId(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.locImpl.snippet = ""
-  if s.typ.returnType != nil:
+  disp.loc.r = ""
+  if s.typ[0] != nil:
    if disp.ast.len > resultPos:
      disp.ast[resultPos].sym = copySym(s.ast[resultPos].sym, idgen)
    else:
@@ -159,14 +153,6 @@ proc fixupDispatcher(meth, disp: PSym; conf: ConfigRef) =

 proc methodDef*(g: ModuleGraph; idgen: IdGenerator; s: 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)
@@ -185,11 +171,6 @@ 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:
@@ -198,7 +179,7 @@ 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)
@@ -210,7 +191,7 @@ proc relevantCol*(methods: seq[PSym], col: int): bool =

 proc cmpSignatures(a, b: PSym, relevantCols: IntSet): int =
  result = 0
-  for col in FirstParamAt..<a.typ.signatureLen:
+  for col in 1..<a.typ.len:
    if contains(relevantCols, col):
      var aa = skipTypes(a.typ[col], skipPtrs)
      var bb = skipTypes(b.typ[col], skipPtrs)
@@ -218,7 +199,7 @@ 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
@@ -237,16 +218,16 @@ proc sortBucket*(a: var seq[PSym], relevantCols: IntSet) =
      a[j] = v
    if h == 1: break

-proc genIfDispatcher*(g: ModuleGraph; methods: seq[PSym], relevantCols: IntSet; idgen: IdGenerator): PSym =
+proc genDispatcher(g: ModuleGraph; methods: seq[PSym], relevantCols: IntSet; idgen: IdGenerator): PSym =
  var base = methods[0].ast[dispatcherPos].sym
  result = base
-  var paramLen = base.typ.signatureLen
+  var paramLen = base.typ.len
  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 FirstParamAt..<paramLen:
+  for col in 1..<paramLen:
    if contains(relevantCols, col):
      let param = base.typ.n[col].sym
      if param.typ.skipTypes(abstractInst).kind in {tyRef, tyPtr}:
@@ -255,7 +236,7 @@ proc genIfDispatcher*(g: ModuleGraph; methods: seq[PSym], relevantCols: IntSet;
  for meth in 0..high(methods):
    var curr = methods[meth]      # generate condition:
    var cond: PNode = nil
-    for col in FirstParamAt..<paramLen:
+    for col in 1..<paramLen:
      if contains(relevantCols, col):
        var isn = newNodeIT(nkCall, base.info, boolType)
        isn.add newSymNode(iss)
@@ -270,7 +251,7 @@ proc genIfDispatcher*(g: ModuleGraph; methods: seq[PSym], relevantCols: IntSet;
          cond = a
        else:
          cond = isn
-    let retTyp = base.typ.returnType
+    let retTyp = base.typ[0]
    let call = newNodeIT(nkCall, base.info, retTyp)
    call.add newSymNode(curr)
    for col in 1..<paramLen:
@@ -296,13 +277,14 @@ proc genIfDispatcher*(g: ModuleGraph; methods: seq[PSym], relevantCols: IntSet;
  nilchecks.flags.incl nfTransf # should not be further transformed
  result.ast[bodyPos] = nilchecks

-proc generateIfMethodDispatchers*(g: ModuleGraph, idgen: IdGenerator) =
+proc generateMethodDispatchers*(g: ModuleGraph, idgen: IdGenerator): PNode =
+  result = newNode(nkStmtList)
  for bucket in 0..<g.methods.len:
    var relevantCols = initIntSet()
-    for col in FirstParamAt..<g.methods[bucket].methods[0].typ.signatureLen:
+    for col in 1..<g.methods[bucket].methods[0].typ.len:
      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)
-    g.addDispatchers genIfDispatcher(g, g.methods[bucket].methods, relevantCols, idgen)
+    result.add newSymNode(genDispatcher(g, g.methods[bucket].methods, relevantCols, idgen))
--- a/compiler/closureiters.nim
+++ b/compiler/closureiters.nim
--- a/compiler/cmdlinehelper.nim
+++ b/compiler/cmdlinehelper.nim
@@ -11,9 +11,7 @@

 import
  options, idents, nimconf, extccomp, commands, msgs,
-  lineinfos, modulegraphs, condsyms, pathutils
-
-import std/[os, parseopt]
+  lineinfos, modulegraphs, condsyms, os, pathutils, parseopt

 proc prependCurDir*(f: AbsoluteFile): AbsoluteFile =
  when defined(unix):
@@ -57,11 +55,6 @@ proc loadConfigsAndProcessCmdLine*(self: NimProg, cache: IdentCache; conf: Confi
  if conf.cmd == cmdNimscript:
    incl(conf.globalOptions, optWasNimscript)
  loadConfigs(DefaultConfig, cache, conf, graph.idgen) # load all config files
-  # restores `conf.notes` after loading config files
-  # because it has overwrites the notes when compiling the system module which
-  # is a foreign module compared to the project
-  if conf.cmd in cmdBackends:
-    conf.notes = conf.mainPackageNotes

  if not self.suggestMode:
    let scriptFile = conf.projectFull.changeFileExt("nims")
--- a/compiler/commands.nim
+++ b/compiler/commands.nim
@@ -24,12 +24,10 @@ 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, enumutils]
+import std/[setutils, os, strutils, parseutils, parseopt, sequtils, strtabs]
 import
  msgs, options, nversion, condsyms, extccomp, platform,
-  wordrecg, nimblecmd, lineinfos, pathutils
-
-import std/pathnorm
+  wordrecg, nimblecmd, lineinfos, pathutils, pathnorm

 from ast import setUseIc, eqTypeFlags, tfGcSafe, tfNoSideEffect

@@ -203,16 +201,11 @@ proc processSpecificNote*(arg: string, state: TSpecialWord, pass: TCmdLinePass,
  else: invalidCmdLineOption(conf, pass, orig, info)

  let isSomeHint = state in {wHint, wHintAsError}
-  let isSomeWarning = state in {wWarning, wWarningAsError}
  template findNote(noteMin, noteMax, name) =
    # unfortunately, hintUser and warningUser clash, otherwise implementation would simplify a bit
    let x = findStr(noteMin, noteMax, id, errUnknown)
    if x != errUnknown: notes = {TNoteKind(x)}
-    else:
-      if isSomeHint or isSomeWarning:
-        message(conf, info, warnUnknownNotes, "unknown $#: $#" % [name, id])
-      else:
-        localError(conf, info, "unknown $#: $#" % [name, id])
+    else: localError(conf, info, "unknown $#: $#" % [name, id])
  case id.normalize
  of "all": # other note groups would be easy to support via additional cases
    notes = if isSomeHint: {hintMin..hintMax} else: {warnMin..warnMax}
@@ -249,7 +242,6 @@ 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)
@@ -305,12 +297,6 @@ proc testCompileOptionArg*(conf: ConfigRef; switch, arg: string, info: TLineInfo
    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)
@@ -364,7 +350,6 @@ proc testCompileOption*(conf: ConfigRef; switch: string, info: TLineInfo): bool
    result = false
  of "panics": result = contains(conf.globalOptions, optPanics)
  of "jsbigint64": result = contains(conf.globalOptions, optJsBigInt64)
-  of "mangle": result = contains(conf.globalOptions, optItaniumMangle)
  else:
    result = false
    invalidCmdLineOption(conf, passCmd1, switch, info)
@@ -460,7 +445,7 @@ template handleStdinOrCmdInput =
    conf.outDir = getNimcacheDir(conf)

 proc handleStdinInput*(conf: ConfigRef) =
-  conf.projectName = conf.stdinFile.string
+  conf.projectName = "stdinfile"
  conf.projectIsStdin = true
  handleStdinOrCmdInput()

@@ -474,9 +459,7 @@ proc parseCommand*(command: string): Command =
  of "cpp", "compiletocpp": cmdCompileToCpp
  of "objc", "compiletooc": cmdCompileToOC
  of "js", "compiletojs": cmdCompileToJS
-  of "nif": cmdCompileToNif
  of "r": cmdCrun
-  of "m": cmdM
  of "run": cmdTcc
  of "check": cmdCheck
  of "e": cmdNimscript
@@ -498,8 +481,6 @@ proc parseCommand*(command: string): Command =
  of "secret": cmdInteractive
  of "nop", "help": cmdNop
  of "jsonscript": cmdJsonscript
-  of "nifc": cmdNifC  # generate C from NIF files
-  of "deps": cmdDeps  # generate .build.nif for nifmake
  else: cmdUnknown

 proc setCmd*(conf: ConfigRef, cmd: Command) =
@@ -511,12 +492,6 @@ proc setCmd*(conf: ConfigRef, cmd: Command) =
  of cmdCompileToCpp: conf.backend = backendCpp
  of cmdCompileToOC: conf.backend = backendObjc
  of cmdCompileToJS: conf.backend = backendJs
-  of cmdCompileToNif: conf.backend = backendNif
-  of cmdNifC:
-    conf.backend = backendC  # NIF to C compilation
-  of cmdM:
-    # cmdM requires optCompress for proper IC handling (include files, etc.)
-    conf.globalOptions.incl optCompress
  else: discard

 proc setCommandEarly*(conf: ConfigRef, command: string) =
@@ -629,13 +604,6 @@ 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 = ""
@@ -681,7 +649,7 @@ 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, pathRelativeToConfig(arg, pass, conf), info, notRelativeToProj=true)
+    conf.nimcacheDir = processPath(conf, arg, info, notRelativeToProj=true)
  of "out", "o":
    expectArg(conf, switch, arg, pass, info)
    let f = splitFile(processPath(conf, arg, info, notRelativeToProj=true).string)
@@ -770,16 +738,6 @@ proc processSwitch*(switch, arg: string, pass: TCmdLinePass, info: TLineInfo;
      conf.globalOptions.excl optCDebug
    else:
      localError(conf, info, "expected native|gdb|on|off but found " & arg)
-  of "mangle":
-    case arg.normalize
-    of "nim":
-      conf.globalOptions.excl optItaniumMangle
-    of "cpp":
-      conf.globalOptions.incl optItaniumMangle
-    else:
-      localError(conf, info, "expected nim|cpp but found " & arg)
-  of "compress":
-    conf.globalOptions.incl optCompress
  of "g": # alias for --debugger:native
    conf.globalOptions.incl optCDebug
    conf.options.incl optLineDir
@@ -825,7 +783,7 @@ 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":
+  of "tlsemulation": 
    processOnOffSwitchG(conf, {optTlsEmulation}, arg, pass, info)
    if optTlsEmulation in conf.globalOptions:
      conf.legacyFeatures.incl emitGenerics
@@ -902,19 +860,11 @@ proc processSwitch*(switch, arg: string, pass: TCmdLinePass, info: TLineInfo;
  of "import":
    expectArg(conf, switch, arg, pass, info)
    if pass in {passCmd2, passPP}:
-      let m = findModule(conf, arg, toFullPath(conf, info)).string
-      if m.len == 0:
-        localError(conf, info, "Cannot resolve filename: " & arg)
-      else:
-        conf.implicitImports.add m
+      conf.implicitImports.add findModule(conf, arg, toFullPath(conf, info)).string
  of "include":
    expectArg(conf, switch, arg, pass, info)
    if pass in {passCmd2, passPP}:
-      let m = findModule(conf, arg, toFullPath(conf, info)).string
-      if m.len == 0:
-        localError(conf, info, "Cannot resolve filename: " & arg)
-      else:
-        conf.implicitIncludes.add m
+      conf.implicitIncludes.add findModule(conf, arg, toFullPath(conf, info)).string
  of "listcmd":
    processOnOffSwitchG(conf, {optListCmd}, arg, pass, info)
  of "asm":
@@ -948,12 +898,6 @@ proc processSwitch*(switch, arg: string, pass: TCmdLinePass, info: TLineInfo;
    discard parseSaturatedNatural(arg, value)
    if not value > 0: localError(conf, info, "maxLoopIterationsVM must be a positive integer greater than zero")
    conf.maxLoopIterationsVM = value
-  of "maxcalldepthvm":
-    expectArg(conf, switch, arg, pass, info)
-    var value: int = 2_000
-    discard parseSaturatedNatural(arg, value)
-    if value <= 0: localError(conf, info, "maxCallDepthVM must be a positive integer greater than zero")
-    conf.maxCallDepthVM = value
  of "errormax":
    expectArg(conf, switch, arg, pass, info)
    # Note: `nim check` (etc) can overwrite this.
@@ -963,10 +907,6 @@ proc processSwitch*(switch, arg: string, pass: TCmdLinePass, info: TLineInfo;
    var value: int = 0
    discard parseSaturatedNatural(arg, value)
    conf.errorMax = if value == 0: high(int) else: value
-  of "stdinfile":
-    expectArg(conf, switch, arg, pass, info)
-    conf.stdinFile = if os.isAbsolute(arg): AbsoluteFile(arg)
-                     else: AbsoluteFile(getCurrentDir() / arg)
  of "verbosity":
    expectArg(conf, switch, arg, pass, info)
    let verbosity = parseInt(arg)
@@ -1000,8 +940,7 @@ proc processSwitch*(switch, arg: string, pass: TCmdLinePass, info: TLineInfo;
      # xxx maybe also ic, since not in help?
    if pass in {passCmd2, passPP}:
      case arg.normalize
-      of "on": conf.ic = true
-      of "legacy": conf.symbolFiles = v2Sf
+      of "on": conf.symbolFiles = v2Sf
      of "off": conf.symbolFiles = disabledSf
      of "writeonly": conf.symbolFiles = writeOnlySf
      of "readonly": conf.symbolFiles = readOnlySf
--- a/compiler/concepts.nim
+++ b/compiler/concepts.nim
@@ -11,15 +11,13 @@
 ## for details. Note this is a first implementation and only the "Concept matching"
 ## section has been implemented.

-import ast, semdata, lookups, lineinfos, idents, msgs, renderer, types, layeredtable
-
-import std/sets
+import ast, astalgo, semdata, lookups, lineinfos, idents, msgs, renderer, types, intsets

 when defined(nimPreviewSlimSystem):
  import std/assertions

 const
-  logBindings = when defined(debugConcepts): true else: false
+  logBindings = false

 ## Code dealing with Concept declarations
 ## --------------------------------------
@@ -28,9 +26,9 @@ 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, c.idgen, ow)
-  s.typ.incl {tfUnresolved, tfPacked}
-  s.typ.add newType(tyEmpty, c.idgen, ow)
+  s.typ = newType(tyTypeDesc, nextTypeId(c.idgen), ow)
+  s.typ.flags.incl {tfUnresolved, tfPacked}
+  s.typ.add newType(tyEmpty, nextTypeId(c.idgen), ow)
  addDecl(c, s, info)

 proc semConceptDecl(c: PContext; n: PNode): PNode =
@@ -70,418 +68,157 @@ proc semConceptDeclaration*(c: PContext; n: PNode): PNode =
 ## ----------------

 type
-  MatchFlags* = enum
-    mfDontBind  # Do not bind generic parameters
-    mfCheckGeneric  # formal <- formal comparison as opposed to formal <- operand
-
-  ConceptTypePair = tuple[conceptId, typeId: ItemId]
-    ## Pair of (concept type id, implementation type id) used for cycle detection
-
  MatchCon = object ## Context we pass around during concept matching.
-    bindings: LayeredIdTable
-    marker: HashSet[ConceptTypePair] ## Tracks (concept, type) pairs being checked to detect cycles.
+    inferred: seq[(PType, PType)] ## we need a seq here so that we can easily undo inferences \
+      ## that turned out to be wrong.
+    marker: IntSet ## Some protection against wild runaway recursions.
    potentialImplementation: PType ## the concrete type that might match the concept we try to match.
    magic: TMagic  ## mArrGet and mArrPut is wrong in system.nim and
                   ## cannot be fixed that easily.
                   ## Thus we special case it here.
-    concpt: PType  ## current concept being evaluated
-    flags: set[MatchFlags]
-
-  MatchKind = enum
-    mkNoMatch, mkSubset, mkSame
-
-const
-  asymmetricConceptParamMods = {tyVar, tySink, tyLent, tyOwned, tyAlias, tyInferred} # param modifiers that to not have to match implementation -> concept
-  bindableTypes = {tyGenericParam, tyOr, tyTypeDesc}
-
-proc conceptMatchNode(c: PContext; n: PNode; m: var MatchCon): bool
-
-proc matchType(c: PContext; fo, ao: PType; m: var MatchCon): bool
-
-proc matchReturnType(c: PContext; f, a: PType; m: var MatchCon): bool
-
-proc processConcept(c: PContext; concpt, invocation: PType, bindings: var LayeredIdTable; m: var MatchCon): bool

 proc existingBinding(m: MatchCon; key: PType): PType =
  ## checks if we bound the type variable 'key' already to some
  ## concrete type.
-  result = m.bindings.lookup(key)
-  if result == nil:
-    result = key
+  for i in 0..<m.inferred.len:
+    if m.inferred[i][0] == key: return m.inferred[i][1]
+  return nil

-const
-    ignorableForArgType = {tyVar, tySink, tyLent, tyOwned, tyAlias, tyInferred}
+proc conceptMatchNode(c: PContext; n: PNode; m: var MatchCon): bool

-proc unrollGenericParam(param: PType): PType =
-  result = param.skipTypes(ignorableForArgType)
-  while result.kind in {tyGenericParam, tyTypeDesc} and result.hasElementType and result.elementType.kind != tyNone:
-    result = result.elementType
-
-proc bindParam(c: PContext, m: var MatchCon; key, v: PType): bool {. discardable .} =
-  if v.kind == tyTypeDesc:
-    return false
-  var value = unrollGenericParam(v)
-  if value.kind == tyGenericParam:
-    value = existingBinding(m, value)
-    if value.kind == tyGenericParam:
-      if value.hasElementType:
-        value = value.elementType
-      else:
-        return true
-  if value.kind == tyStatic:
-    return false
-
-  if m.magic in {mArrPut, mArrGet} and value.kind in arrPutGetMagicApplies:
-    value = value.last
-  
-  let old = existingBinding(m, key)
-  if old != key:
-    # check previously bound value
-    if not matchType(c, old, value, m):
-      return false
-  elif key.hasElementType and not key.elementType.isNil and key.elementType.kind != tyNone:
-    # check constaint
-    if matchType(c, unrollGenericParam(key), value, m) == false:
-      return false
-  
-  when logBindings: echo "bind table adding '", key, "', ", value
-  assert value != nil
-  assert value.kind != tyVoid
-  m.bindings.put(key, value)
-  return true
-
-proc defSignatureType(n: PNode): PType = n[0].sym.typ
-
-proc conceptBody*(n: PType): PNode = n.n.lastSon
-
-proc acceptsAllTypes(t: PType): bool=
-  result = false
-  if t.kind == tyAnything:
-    result = true
-  elif t.kind == tyGenericParam:
-    if tfImplicitTypeParam in t.flags:
-      result = true
-    if not t.hasElementType or t.elementType.kind == tyNone:
-      result = true
-
-proc procDefSignature(s: PSym): PNode {. deprecated .} = 
-  var nc = s.ast.copyNode()
-  for i in 0 .. 5:
-    nc.add s.ast[i]
-  nc
-
-proc matchKids(c: PContext; f, a: PType; m: var MatchCon, start=0): bool=
-  result = true
-  for i in start ..< f.kidsLen - ord(f.kind in {tyGenericInst, tyGenericInvocation}):
-    if not matchType(c, f[i], a[i], m): return false
-
-iterator traverseTyOr(t: PType): PType {. closure .}=
-  for i in t.kids:
-    case i.kind:
-    of tyGenericParam:
-      if i.hasElementType:
-        for s in traverseTyOr(i.elementType):
-          yield s
-      else:
-        yield i
-    else:
-      yield i
-
-proc matchConceptToImpl(c: PContext, f, potentialImpl: PType; m: var MatchCon): bool =
-  assert not(potentialImpl.reduceToBase.kind == tyConcept)
-  let concpt = f.reduceToBase
-
-  # Handle self-referential concepts: when a concept references itself in its body
-  # (e.g., `A = concept; proc test(x: Self, y: A)`), the inner type A has n=nil.
-  # We detect this by checking if the concept has the same symbol name as the
-  # one we're currently matching and has no body (n=nil).
-  if concpt.n.isNil:
-    if concpt.sym != nil and m.concpt.sym != nil and
-       concpt.sym == m.concpt.sym:
-      # Self-reference: check if potentialImpl matches what we're already checking
-      return potentialImpl.id == m.potentialImplementation.id
-    # Concept without body that's not a self-reference - cannot match
-    return false
-
-  # Cycle detection: track (concept, type) pairs to prevent infinite recursion.
-  # Returns true on cycle (coinductive semantics) to support co-dependent concepts.
-  let pair: ConceptTypePair = (concpt.itemId, potentialImpl.itemId)
-  if pair in m.marker:
-    return true
-  m.marker.incl pair
-
-  var efPot = potentialImpl
-  if potentialImpl.isSelf:
-    if m.concpt.n == concpt.n:
-      m.marker.excl pair
-      return true
-    efPot = m.potentialImplementation
-
-  var oldBindings = m.bindings
-  m.bindings = newTypeMapLayer(m.bindings)
-  let oldPotentialImplementation = m.potentialImplementation
-  m.potentialImplementation = efPot
-  let oldConcept = m.concpt
-  m.concpt = concpt
-
-  var invocation: PType = nil
-  if f.kind in {tyGenericInvocation, tyGenericInst}:
-    invocation = f
-  result = processConcept(c, concpt, invocation, oldBindings, m)
-  m.potentialImplementation = oldPotentialImplementation
-  m.concpt = oldConcept
-  m.bindings = oldBindings
-  m.marker.excl pair
-
-proc cmpConceptDefs(c: PContext, fn, an: PNode, m: var MatchCon): bool=
-  if fn.kind != an.kind:
-    return false
-  if fn[namePos].sym.name != an[namePos].sym.name:
-    return false
-  let
-    ft = fn.defSignatureType
-    at = an.defSignatureType
-  if ft.len != at.len:
-    return false
-  
-  for i in 1 ..< ft.n.len:
-    m.bindings = m.bindings.newTypeMapLayer()
-    
-    let aType = at.n[i].typ
-    let fType = ft.n[i].typ
-    
-    if aType.isSelf and fType.isSelf:
-      continue
-    
-    if not matchType(c, fType, aType, m):
-      m.bindings.setToPreviousLayer()
-      return false
-  result = true
-  if not matchReturnType(c, ft.returnType, at.returnType, m):
-    m.bindings.setToPreviousLayer()
-    result = false
-
-proc conceptsMatch(c: PContext, fc, ac: PType; m: var MatchCon): MatchKind =
-  # XXX: In the future this may need extra parameters to carry info for container types
-  if fc.n == ac.n:
-    # This will have to take generic parameters into account at some point
-    return mkSame
-  let
-    fn = fc.conceptBody
-    an = ac.conceptBody
-    sameLen = fc.len == ac.len
-  var match = false
-  for fdef in fn:
-    var cmpResult = false
-    for ia, ndef in an:
-      match = cmpConceptDefs(c, fdef, ndef, m)
-      if match:
-        break
-    if not match:
-      return mkNoMatch
-  return mkSubset
-
-proc isObjectSubtype(f, a: PType): bool =
-  var t = a
-  result = false
-  while t != nil:
-    t = t.baseClass
-    if t == nil:
-      break
-    t = t.skipTypes({tyPtr,tyRef})
-    if t == nil:
-      break
-    if t.kind != tyObject:
-      break
-    if sameObjectTypes(f, t):
-      result = true
-      break
-
-proc matchType(c: PContext; fo, ao: PType; m: var MatchCon): bool =
+proc matchType(c: PContext; f, a: PType; m: var MatchCon): bool =
  ## The heart of the concept matching process. 'f' is the formal parameter of some
  ## routine inside the concept that we're looking for. 'a' is the formal parameter
  ## of a routine that might match.
-  
-  var
-    a = ao
-    f = fo
-  if a.isSelf:
-    if m.magic in {mArrPut, mArrGet}:
-      return false
-    a = m.potentialImplementation
-  if a.kind in bindableTypes:
-    a = existingBinding(m, ao)
-    if a == ao and a.kind == tyGenericParam and a.hasElementType and a.elementType.kind != tyNone:
-      a = a.elementType
-  
-  if f.isConcept:
-    if a.acceptsAllTypes:
-      return false
-    if a.skipTypes(ignorableForArgType).isConcept:
-      # if f is a subset of a then any match to a will also match f. Not the other way around
-      return conceptsMatch(c, a.reduceToBase, f.reduceToBase, m) >= mkSubset
-    else:
-      return matchConceptToImpl(c, f, a, m)
-  
-  result = false
-
+  const
+    ignorableForArgType = {tyVar, tySink, tyLent, tyOwned, tyGenericInst, tyAlias, tyInferred}
  case f.kind
  of tyAlias:
-    result = matchType(c, f.skipModifier, a, m)
+    result = matchType(c, f.lastSon, a, m)
  of tyTypeDesc:
    if isSelf(f):
-      let ua = a.skipTypes(asymmetricConceptParamMods)
-      if m.magic in {mArrPut, mArrGet}:
-        if m.potentialImplementation.reduceToBase.kind in arrPutGetMagicApplies:
-          bindParam(c, m, a, last m.potentialImplementation)
-          result = true
-      #elif ua.isConcept:
-      #  result = matchType(c, m.concpt, ua, m)
-      else:
-        result = matchType(c, a.skipTypes(ignorableForArgType), m.potentialImplementation, m)
+      #let oldLen = m.inferred.len
+      result = matchType(c, a, m.potentialImplementation, m)
+      #echo "self is? ", result, " ", a.kind, " ", a, " ", m.potentialImplementation, " ", m.potentialImplementation.kind
+      #m.inferred.setLen oldLen
+      #echo "A for ", result, " to ", typeToString(a), " to ", typeToString(m.potentialImplementation)
    else:
-      if a.kind == tyTypeDesc:
-        if not(a.hasElementType) or a.elementType.kind == tyNone:
+      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
+      else:
+        result = false
+
+  of tyGenericInvocation:
+    result = false
+    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:
+          if not matchType(c, f[i], a[i], m): return false
+        return true
+  of tyGenericParam:
+    let ak = a.skipTypes({tyVar, tySink, tyLent, tyOwned})
+    if ak.kind in {tyTypeDesc, tyStatic} and not isSelf(ak):
+      result = false
+    else:
+      let old = existingBinding(m, f)
+      if old == nil:
+        if f.len > 0 and f[0].kind != tyNone:
+          # also check the generic's constraints:
+          let oldLen = m.inferred.len
+          result = matchType(c, f[0], 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))
          result = true
-        elif f.hasElementType:
-          result = matchType(c, f.elementType, a.elementType, m)
+        else:
+          when logBindings: echo "C adding ", f, " ", ak
+          m.inferred.add((f, ak))
+          #echo "binding ", typeToString(ak), " to ", typeToString(f)
+          result = true
+      elif not m.marker.containsOrIncl(old.id):
+        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.elementType, a.elementType, m)
+      result = matchType(c, f[0], a[0], m)
    elif m.magic == mArrPut:
-      result = matchType(c, f.elementType, a, m)
-  of tyEnum, tyObject, tyDistinct:
-    if a.kind in ignorableForArgType:
-      result = matchType(c, f, a.skipTypes(ignorableForArgType), m)
+      result = matchType(c, f[0], a, m)
    else:
-      if a.kind == tyGenericInst:
-        # tyOr does this to generic typeclasses
-        result = a.base.sym == f.sym
-      else:
-        result = sameType(f, a)
-      if not result and f.kind == tyObject and a.kind == tyObject:
-        result = isObjectSubtype(f, a)
+      result = false
+  of tyEnum, tyObject, tyDistinct:
+    result = sameType(f, a)
  of tyEmpty, tyString, tyCstring, tyPointer, tyNil, tyUntyped, tyTyped, tyVoid:
    result = a.skipTypes(ignorableForArgType).kind == f.kind
  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.hasElementType and ak.elementType.kind == tyOrdinal)
-  of tyArray, tyTuple, tyVarargs, tyOpenArray, tyRange, tySequence, tyRef, tyPtr:
-    if f.kind == tyArray and f.kidsLen == 3 and a.kind == tyArray:
-      # XXX: this is a work-around!
-      # system.nim creates these for the magic array typeclass
-      result = true
-    else:
-      let ak = a.skipTypes(ignorableForArgType - {f.kind})
-      if ak.kind == f.kind:
-        if f.base.kind == tyNone:
-          result = true
-        elif f.kidsLen == ak.kidsLen:
-          result = matchKids(c, f, ak, m)
-  of tyGenericInvocation, tyGenericInst:
+       (ak.kind == tyGenericParam and ak.len > 0 and ak[0].kind == tyOrdinal)
+  of tyConcept:
+    let oldLen = m.inferred.len
+    let oldPotentialImplementation = m.potentialImplementation
+    m.potentialImplementation = a
+    result = conceptMatchNode(c, f.n.lastSon, m)
+    m.potentialImplementation = oldPotentialImplementation
+    if not result:
+      m.inferred.setLen oldLen
+  of tyArray, tyTuple, tyVarargs, tyOpenArray, tyRange, tySequence, tyRef, tyPtr,
+     tyGenericInst:
    result = false
-    let ea = a.skipTypes(ignorableForArgType)
-    if ea.kind in {tyGenericInst, tyGenericInvocation}:
-      var
-        k1 = f.kidsLen - ord(f.kind == tyGenericInst)
-        k2 = ea.kidsLen - ord(ea.kind == tyGenericInst)
-      if sameType(f.genericHead, ea.genericHead) and k1 == k2:
-        result = true
-        for i in 1 ..< k2:
-          if not matchType(c, f[i], ea[i], m):
-            result = false
-            break
-    elif f.kind == tyGenericInvocation:
-      # bind potential generic constraints into body
-      let body = f.base
-      for i in 1 ..< len(f):
-        bindParam(c,m,body[i-1], f[i])
-      result = matchType(c, body, a, m)
-    else: # tyGenericInst
-      result = matchType(c, f.last, a, m)
-  of tyOrdinal:
-    result = isOrdinalType(a, allowEnumWithHoles = false) or a.kind == tyGenericParam
-  of tyStatic:
-    var scomp = f.base
-    if scomp.kind == tyGenericParam:
-      if f.base.kidsLen > 0:
-        scomp = scomp.base
-    if a.kind == tyStatic:
-      result = matchType(c, scomp, a.base, m)
-    else:
-      result = matchType(c, scomp, a, m)
-  of tyGenericParam:
-    if a.acceptsAllTypes:
-      discard bindParam(c, m, f, a)
-      result = f.acceptsAllTypes
-    else:
-      result = bindParam(c, m, f, a)
-  of tyAnything:
-    result = true
-  of tyNot:
-    if a.kind == tyNot:
-      result = matchType(c, f.elementType, a.elementType, m)
-    else:
-      m.bindings = m.bindings.newTypeMapLayer()
-      result = not matchType(c, f.elementType, a, m)
-      m.bindings.setToPreviousLayer()
-  of tyAnd:
-    m.bindings = m.bindings.newTypeMapLayer()
-    result = true
-    for ff in traverseTyOr(f):
-      let r = matchType(c, ff, a, m)
-      if not r:
-        m.bindings.setToPreviousLayer()
-        result = false
-        break
-  of tyGenericBody:
-    var ak = a
-    if a.kind == tyGenericBody:
-      ak = last(a)
-    result = matchType(c, last(f), ak, m)
-  of tyCompositeTypeClass:
-    if a.kind == tyCompositeTypeClass:
-      result = matchKids(c, f, a, m)
-    else:
-      result = matchType(c, last(f), a, m)
-  of tyBuiltInTypeClass:
-    let target = f.genericHead.kind
-    result = a.skipTypes(ignorableForArgType).reduceToBase.kind == target
+    let ak = a.skipTypes(ignorableForArgType - {f.kind})
+    if ak.kind == f.kind and f.len == ak.len:
+      for i in 0..<ak.len:
+        if not matchType(c, f[i], ak[i], m): return false
+      return true
  of tyOr:
+    let oldLen = m.inferred.len
    if a.kind == tyOr:
+      # say the concept requires 'int|float|string' if the potentialImplementation
+      # says 'int|string' that is good enough.
      var covered = 0
-      for ff in traverseTyOr(f):
-        for aa in traverseTyOr(a):
-          m.bindings = m.bindings.newTypeMapLayer()
-          let r = matchType(c, ff, aa, m)
+      for i in 0..<f.len:
+        for j in 0..<a.len:
+          let oldLenB = m.inferred.len
+          let r = matchType(c, f[i], a[j], m)
          if r:
            inc covered
            break
-          m.bindings.setToPreviousLayer()
+          m.inferred.setLen oldLenB

-      result = covered >= a.kidsLen
+      result = covered >= a.len
+      if not result:
+        m.inferred.setLen oldLen
    else:
-      for ff in f.kids:
-        m.bindings = m.bindings.newTypeMapLayer()
-        result = matchType(c, ff, a, m)
+      result = false
+      for i in 0..<f.len:
+        result = matchType(c, f[i], a, m)
        if result: break # and remember the binding!
-        m.bindings.setToPreviousLayer()
-  of tySet:
-    result = false
-    if a.kind == tySet:
-      result = matchType(c, f.elementType, a.elementType, m)
+        m.inferred.setLen oldLen
+  of tyNot:
+    if a.kind == tyNot:
+      result = matchType(c, f[0], a[0], m)
+    else:
+      let oldLen = m.inferred.len
+      result = not matchType(c, f[0], a, m)
+      m.inferred.setLen oldLen
+  of tyAnything:
+    result = true
+  of tyOrdinal:
+    result = isOrdinalType(a, allowEnumWithHoles = false) or a.kind == tyGenericParam
  else:
    result = false
-  if result and ao.kind == tyGenericParam:
-    let bf = if f.isSelf: m.potentialImplementation else: f
-    if bindParam(c, m, ao, bf):
-      when logBindings: echo " ^ reverse binding"
-
-proc checkConstraint(c: PContext; f, a: PType; m: var MatchCon): bool =
-  result = matchType(c, f, a, m) or matchType(c, a, f, m)

 proc matchReturnType(c: PContext; f, a: PType; m: var MatchCon): bool =
  ## Like 'matchType' but with extra logic dealing with proc return types
@@ -491,38 +228,30 @@ proc matchReturnType(c: PContext; f, a: PType; m: var MatchCon): bool =
  elif a == nil:
    result = false
  else:
-    result = checkConstraint(c, f, a, m)
+    result = matchType(c, f, a, m)

 proc matchSym(c: PContext; candidate: PSym, n: PNode; m: var MatchCon): bool =
  ## Checks if 'candidate' matches 'n' from the concept body. 'n' is a nkProcDef
  ## or similar.

  # watch out: only add bindings after a completely successful match.
-  m.bindings = m.bindings.newTypeMapLayer()
+  let oldLen = m.inferred.len

  let can = candidate.typ.n
-  let con = defSignatureType(n).n
+  let con = n[0].sym.typ.n
+
  if can.len < con.len:
    # too few arguments, cannot be a match:
    return false
-  
-  if can.len > con.len:
-    # too many arguments (not optional)
-    for i in con.len ..< can.len:
-      if can[i].sym.ast == nil:
-        return false
-  
-  when defined(debugConcepts):
-    echo "considering: ", renderTree(candidate.procDefSignature), " ", candidate.magic
-  
+
  let common = min(can.len, con.len)
  for i in 1 ..< common:
-    if not checkConstraint(c, con[i].typ, can[i].typ, m):
-      m.bindings.setToPreviousLayer()
+    if not matchType(c, con[i].typ, can[i].typ, m):
+      m.inferred.setLen oldLen
      return false
-  
-  if not matchReturnType(c, n.defSignatureType.returnType, candidate.typ.returnType, m):
-    m.bindings.setToPreviousLayer()
+
+  if not matchReturnType(c, n[0].sym.typ[0], candidate.typ[0], m):
+    m.inferred.setLen oldLen
    return false

  # all other parameters have to be optional parameters:
@@ -530,7 +259,7 @@ proc matchSym(c: PContext; candidate: PSym, n: PNode; m: var MatchCon): bool =
    assert can[i].kind == nkSym
    if can[i].sym.ast == nil:
      # has too many arguments one of which is not optional:
-      m.bindings.setToPreviousLayer()
+      m.inferred.setLen oldLen
      return false

  return true
@@ -538,14 +267,12 @@ proc matchSym(c: PContext; candidate: PSym, n: PNode; m: var MatchCon): bool =
 proc matchSyms(c: PContext, n: PNode; kinds: set[TSymKind]; m: var MatchCon): bool =
  ## Walk the current scope, extract candidates which the same name as 'n[namePos]',
  ## 'n' is the nkProcDef or similar from the concept that we try to match.
-  result = false
-  var candidates = searchScopes(c, n[namePos].sym.name, kinds)
-  searchImportsAll(c, n[namePos].sym.name, kinds, candidates)
+  let candidates = searchInScopesAllCandidatesFilterBy(c, n[namePos].sym.name, kinds)
  for candidate in candidates:
+    #echo "considering ", typeToString(candidate.typ), " ", candidate.magic
    m.magic = candidate.magic
-    if matchSym(c, candidate, n, m):
-      result = true
-      break
+    if matchSym(c, candidate, n, m): return true
+  result = false

 proc conceptMatchNode(c: PContext; n: PNode; m: var MatchCon): bool =
  ## Traverse the concept's AST ('n') and see if every declaration inside 'n'
@@ -578,66 +305,35 @@ proc conceptMatchNode(c: PContext; n: PNode; m: var MatchCon): bool =
    # error was reported earlier.
    result = false

-proc fixBindings(bindings: var LayeredIdTable; concpt: PType; invocation: PType; m: var MatchCon) =
-  # invocation != nil means we have a non-atomic concept:
-  if invocation != nil and invocation.kind == tyGenericInvocation:
-    assert concpt.sym.typ.kind == tyGenericBody
-    
-    for i in 0 .. concpt.sym.typ.len - 1:
-      let thisSym = concpt.sym.typ[i]
-      if lookup(bindings, thisSym) != nil:
-        # dont trust the bindings over existing ones
-        continue
-      let found = m.bindings.lookup(thisSym)
-      if found != nil:
-        when logBindings: echo "Invocation bind: ", thisSym, " ", found
-        bindings.put(thisSym, found)
-    
-    # bind even more generic parameters
-    let genBody = invocation.base
-    assert genBody.kind == tyGenericBody
-    for i in FirstGenericParamAt ..< invocation.kidsLen:
-      let bpram = genBody[i - 1]
-      if lookup(bindings, invocation[i]) != nil:
-        # dont trust the bindings over existing ones
-        continue
-      let boundV = lookup(bindings, bpram)
-      when logBindings: echo "generic body bind: '", invocation[i], "' '", boundV, "'"
-      if boundV != nil:
-        bindings.put(invocation[i], boundV)
-  bindings.put(concpt, m.potentialImplementation)
-
-proc processConcept(c: PContext; concpt, invocation: PType, bindings: var LayeredIdTable; m: var MatchCon): bool =
-  m.bindings = m.bindings.newTypeMapLayer()
-  if invocation != nil and invocation.kind == tyGenericInst:
-    let genericBody = invocation.base
-    for i in 1..<invocation.kidsLen-1:
-      # instGenericContainer can bind `tyVoid`
-      if invocation[i].kind != tyVoid:
-        bindParam(c, m, genericBody[i-1], invocation[i])
-  result = conceptMatchNode(c, concpt.conceptBody, m)
-  if result and mfDontBind notin m.flags:
-    fixBindings(bindings, concpt, invocation, m)
-
-proc conceptMatch*(c: PContext; concpt, arg: PType; bindings: var LayeredIdTable; invocation: PType, flags: set[MatchFlags] = {}): bool =
+proc conceptMatch*(c: PContext; concpt, arg: PType; bindings: var TIdTable; 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
+  ## we extract its AST via 'concpt.n.lastSon'). 'arg' is the type that might fullfill the
  ## concept's requirements. If so, we return true and fill the 'bindings' with pairs of
  ## (typeVar, instance) pairs. ('typeVar' is usually simply written as a generic 'T'.)
  ## 'invocation' can be nil for atomic concepts. For non-atomic concepts, it contains the
  ## `C[S, T]` parent type that we look for. We need this because we need to store bindings
  ## for 'S' and 'T' inside 'bindings' on a successful match. It is very important that
  ## we do not add any bindings at all on an unsuccessful match!
-  var m = MatchCon(bindings: bindings, potentialImplementation: arg, concpt: concpt, flags: flags, marker: initHashSet[ConceptTypePair]())
-  if arg.isConcept:
-    result = conceptsMatch(c, concpt.reduceToBase, arg.reduceToBase, m) >= mkSubset
-  elif arg.acceptsAllTypes:
-    # XXX: I think this is wrong, or at least partially wrong. Can still test ambiguous types
-    result = false
-  elif mfCheckGeneric in m.flags:
-    # prioritize concepts the least. Specifically if the arg is not a catch all as per above
-    result = true
-  else:
-    result = processConcept(c, concpt, invocation, bindings, m)
-
-  
+  var m = MatchCon(inferred: @[], potentialImplementation: arg)
+  result = conceptMatchNode(c, concpt.n.lastSon, m)
+  if result:
+    for (a, b) in m.inferred:
+      if b.kind == tyGenericParam:
+        var dest = b
+        while true:
+          dest = existingBinding(m, dest)
+          if dest == nil or dest.kind != tyGenericParam: break
+        if dest != nil:
+          bindings.idTablePut(a, dest)
+          when logBindings: echo "A bind ", a, " ", dest
+      else:
+        bindings.idTablePut(a, b)
+        when logBindings: echo "B bind ", a, " ", b
+    # we have a match, so bind 'arg' itself to 'concpt':
+    bindings.idTablePut(concpt, arg)
+    # invocation != nil means we have a non-atomic concept:
+    if invocation != nil and arg.kind == tyGenericInst and invocation.len == arg.len-1:
+      # bind even more generic parameters
+      assert invocation.kind == tyGenericInvocation
+      for i in 1 ..< invocation.len:
+        bindings.idTablePut(invocation[i], arg[i])
--- a/compiler/condsyms.nim
+++ b/compiler/condsyms.nim
@@ -10,7 +10,7 @@
 # This module handles the conditional symbols.

 import
-  std/strtabs
+  strtabs

 from options import Feature
 from lineinfos import hintMin, hintMax, warnMin, warnMax
@@ -143,6 +143,7 @@ proc initDefines*(symbols: StringTableRef) =
  defineSymbol("nimHasTemplateRedefinitionPragma")
  defineSymbol("nimHasCstringCase")
  defineSymbol("nimHasCallsitePragma")
+  defineSymbol("nimHasAmbiguousEnumHint")

  defineSymbol("nimHasWarnCastSizes") # deadcode
  defineSymbol("nimHasOutParams")
@@ -157,21 +158,6 @@ proc initDefines*(symbols: StringTableRef) =
  defineSymbol("nimAllowNonVarDestructor")
  defineSymbol("nimHasQuirky")
  defineSymbol("nimHasEnsureMove")
-  defineSymbol("nimHasNoReturnError")

-  defineSymbol("nimUseStrictDefs") # deadcode
+  defineSymbol("nimUseStrictDefs")
  defineSymbol("nimHasNolineTooLong")
-
-  defineSymbol("nimHasCastExtendedVm")
-  defineSymbol("nimHasWarnStdPrefix")
-
-  defineSymbol("nimHasVtables")
-  defineSymbol("nimHasGenericsOpenSym2")
-  defineSymbol("nimHasGenericsOpenSym3")
-  defineSymbol("nimHasJsNoLambdaLifting")
-  defineSymbol("nimHasDefaultFloatRoundtrip")
-  defineSymbol("nimHasXorSet")
-
-  defineSymbol("nimHasSetLengthSeqUninitMagic")
-  defineSymbol("nimHasPreviewDuplicateModuleError")
-
--- a/compiler/depends.nim
+++ b/compiler/depends.nim
@@ -14,7 +14,7 @@ import options, ast, ropes, pathutils, msgs, lineinfos
 import modulegraphs

 import std/[os, parseutils]
-import std/strutils except addf
+import strutils except addf
 import std/private/globs

 when defined(nimPreviewSlimSystem):
--- a/compiler/deps.nim
+++ b/compiler/deps.nim
@@ -1,340 +0,0 @@
-#
-#
-#           The Nim Compiler
-#        (c) Copyright 2025 Andreas Rumpf
-#
-#    See the file "copying.txt", included in this
-#    distribution, for details about the copyright.
-#
-
-## Generate a .build.nif file for nifmake from a Nim project.
-## This enables incremental and parallel compilation using the `m` switch.
-
-import std / [os, tables, sets, times, osproc, strutils]
-import options, msgs, lineinfos
-
-import "../dist/nimony/src/lib" / [nifstreams, nifcursors, bitabs, nifreader, nifbuilder]
-import "../dist/nimony/src/gear2" / modnames
-
-type
-  FilePair = object
-    nimFile: string
-    modname: string
-
-  Node = ref object
-    files: seq[FilePair]  # main file + includes
-    deps: seq[int]        # indices into DepContext.nodes
-    id: int
-
-  DepContext = object
-    config: ConfigRef
-    nifler: string
-    nodes: seq[Node]
-    processedModules: Table[string, int]  # modname -> node index
-    includeStack: seq[string]
-
-proc toPair(c: DepContext; f: string): FilePair =
-  FilePair(nimFile: f, modname: moduleSuffix(f, cast[seq[string]](c.config.searchPaths)))
-
-proc depsFile(c: DepContext; f: FilePair): string =
-  getNimcacheDir(c.config).string / f.modname & ".deps.nif"
-
-proc parsedFile(c: DepContext; f: FilePair): string =
-  getNimcacheDir(c.config).string / f.modname & ".p.nif"
-
-proc semmedFile(c: DepContext; f: FilePair): string =
-  getNimcacheDir(c.config).string / f.modname & ".nif"
-
-proc findNifler(): string =
-  # Look for nifler in common locations
-  result = findExe("nifler")
-  if result.len == 0:
-    # Try relative to nim executable
-    let nimDir = getAppDir()
-    result = nimDir / "nifler"
-    if not fileExists(result):
-      result = nimDir / ".." / "nimony" / "bin" / "nifler"
-      if not fileExists(result):
-        result = ""
-
-proc runNifler(c: DepContext; nimFile: string): bool =
-  ## Run nifler deps on a file if needed. Returns true on success.
-  let pair = c.toPair(nimFile)
-  let depsPath = c.depsFile(pair)
-
-  # Check if deps file is up-to-date
-  if fileExists(depsPath) and fileExists(nimFile):
-    if getLastModificationTime(depsPath) > getLastModificationTime(nimFile):
-      return true  # Already up-to-date
-
-  # Create output directory if needed
-  createDir(parentDir(depsPath))
-
-  # Run nifler deps
-  let cmd = quoteShell(c.nifler) & " deps " & quoteShell(nimFile) & " " & quoteShell(depsPath)
-  let exitCode = execShellCmd(cmd)
-  result = exitCode == 0
-
-proc resolveFile(c: DepContext; origin, toResolve: string): string =
-  ## Resolve an import path relative to origin file
-  # Handle std/ prefix
-  var path = toResolve
-  if path.startsWith("std/"):
-    path = path.substr(4)
-
-  # Try relative to origin first
-  let originDir = parentDir(origin)
-  result = originDir / path.addFileExt("nim")
-  if fileExists(result):
-    return result
-
-  # Try search paths
-  for searchPath in c.config.searchPaths:
-    result = searchPath.string / path.addFileExt("nim")
-    if fileExists(result):
-      return result
-
-  result = ""
-
-proc traverseDeps(c: var DepContext; pair: FilePair; current: Node)
-
-proc processInclude(c: var DepContext; includePath: string; current: Node) =
-  let resolved = resolveFile(c, current.files[current.files.len - 1].nimFile, includePath)
-  if resolved.len == 0 or not fileExists(resolved):
-    return
-
-  # Check for recursive includes
-  for s in c.includeStack:
-    if s == resolved:
-      return  # Skip recursive include
-
-  c.includeStack.add resolved
-  current.files.add c.toPair(resolved)
-  traverseDeps(c, c.toPair(resolved), current)
-  discard c.includeStack.pop()
-
-proc processImport(c: var DepContext; importPath: string; current: Node) =
-  let resolved = resolveFile(c, current.files[0].nimFile, importPath)
-  if resolved.len == 0 or not fileExists(resolved):
-    return
-
-  let pair = c.toPair(resolved)
-  let existingIdx = c.processedModules.getOrDefault(pair.modname, -1)
-
-  if existingIdx == -1:
-    # New module - create node and process it
-    let newNode = Node(files: @[pair], id: c.nodes.len)
-    current.deps.add newNode.id
-    c.processedModules[pair.modname] = newNode.id
-    c.nodes.add newNode
-    traverseDeps(c, pair, newNode)
-  else:
-    # Already processed - just add dependency
-    if existingIdx notin current.deps:
-      current.deps.add existingIdx
-
-proc readDepsFile(c: var DepContext; pair: FilePair; current: Node) =
-  ## Read a .deps.nif file and process imports/includes
-  let depsPath = c.depsFile(pair)
-  if not fileExists(depsPath):
-    return
-
-  var s = nifstreams.open(depsPath)
-  defer: nifstreams.close(s)
-  discard processDirectives(s.r)
-
-  var t = next(s)
-  if t.kind != ParLe:
-    return
-
-  # Skip to content (past stmts tag)
-  t = next(s)
-
-  while t.kind != EofToken:
-    if t.kind == ParLe:
-      let tag = pool.tags[t.tagId]
-      case tag
-      of "import", "fromimport":
-        # Read import path
-        t = next(s)
-        # Check for "when" marker (conditional import)
-        if t.kind == Ident and pool.strings[t.litId] == "when":
-          t = next(s)  # skip it, still process the import
-        # Handle path expression (could be ident, string, or infix like std/foo)
-        var importPath = ""
-        if t.kind == Ident:
-          importPath = pool.strings[t.litId]
-        elif t.kind == StringLit:
-          importPath = pool.strings[t.litId]
-        elif t.kind == ParLe and pool.tags[t.tagId] == "infix":
-          # Handle std / foo style imports
-          t = next(s)  # skip infix tag
-          if t.kind == Ident:  # operator (/)
-            t = next(s)
-          if t.kind == Ident:  # first part (std)
-            importPath = pool.strings[t.litId]
-            t = next(s)
-          if t.kind == Ident:  # second part (foo)
-            importPath = importPath & "/" & pool.strings[t.litId]
-        if importPath.len > 0:
-          processImport(c, importPath, current)
-        # Skip to end of import node
-        var depth = 1
-        while depth > 0:
-          t = next(s)
-          if t.kind == ParLe: inc depth
-          elif t.kind == ParRi: dec depth
-      of "include":
-        # Read include path
-        t = next(s)
-        if t.kind == Ident and pool.strings[t.litId] == "when":
-          t = next(s)  # skip conditional marker
-        var includePath = ""
-        if t.kind == Ident:
-          includePath = pool.strings[t.litId]
-        elif t.kind == StringLit:
-          includePath = pool.strings[t.litId]
-        if includePath.len > 0:
-          processInclude(c, includePath, current)
-        # Skip to end
-        var depth = 1
-        while depth > 0:
-          t = next(s)
-          if t.kind == ParLe: inc depth
-          elif t.kind == ParRi: dec depth
-      else:
-        # Skip unknown node
-        var depth = 1
-        while depth > 0:
-          t = next(s)
-          if t.kind == ParLe: inc depth
-          elif t.kind == ParRi: dec depth
-    t = next(s)
-
-proc traverseDeps(c: var DepContext; pair: FilePair; current: Node) =
-  ## Process a module: run nifler and read deps
-  if not runNifler(c, pair.nimFile):
-    rawMessage(c.config, errGenerated, "nifler failed for: " & pair.nimFile)
-    return
-  readDepsFile(c, pair, current)
-
-proc generateBuildFile(c: DepContext): string =
-  ## Generate the .build.nif file for nifmake
-  result = getNimcacheDir(c.config).string / c.nodes[0].files[0].modname & ".build.nif"
-
-  var b = nifbuilder.open(result)
-  defer: b.close()
-
-  b.addHeader("nim deps", "nifmake")
-  b.addTree "stmts"
-
-  # Define nifler command
-  b.addTree "cmd"
-  b.addSymbolDef "nifler"
-  b.addStrLit c.nifler
-  b.addStrLit "parse"
-  b.addStrLit "--deps"
-  b.addTree "input"
-  b.endTree()
-  b.addTree "output"
-  b.endTree()
-  b.endTree()
-
-  # Define nim m command
-  b.addTree "cmd"
-  b.addSymbolDef "nim_m"
-  b.addStrLit getAppFilename()
-  b.addStrLit "m"
-  # Add search paths
-  for p in c.config.searchPaths:
-    b.addStrLit "--path:" & p.string
-  b.addTree "input"
-  b.addIntLit 0
-  b.endTree()
-  b.endTree()
-
-  # Build rules for parsing (nifler)
-  var seenFiles = initHashSet[string]()
-  for node in c.nodes:
-    for pair in node.files:
-      let parsed = c.parsedFile(pair)
-      if not seenFiles.containsOrIncl(parsed):
-        b.addTree "do"
-        b.addIdent "nifler"
-        b.addTree "input"
-        b.addStrLit pair.nimFile
-        b.endTree()
-        b.addTree "output"
-        b.addStrLit parsed
-        b.endTree()
-        b.addTree "output"
-        b.addStrLit c.depsFile(pair)
-        b.endTree()
-        b.endTree()
-
-  # Build rules for semantic checking (nim m)
-  for i in countdown(c.nodes.len - 1, 0):
-    let node = c.nodes[i]
-    let pair = node.files[0]
-    b.addTree "do"
-    b.addIdent "nim_m"
-    # Input: all parsed files for this module
-    for f in node.files:
-      b.addTree "input"
-      b.addStrLit c.parsedFile(f)
-      b.endTree()
-    # Also depend on semmed files of dependencies
-    for depIdx in node.deps:
-      b.addTree "input"
-      b.addStrLit c.semmedFile(c.nodes[depIdx].files[0])
-      b.endTree()
-    # Output: semmed file
-    b.addTree "output"
-    b.addStrLit c.semmedFile(pair)
-    b.endTree()
-    b.addTree "args"
-    b.addStrLit pair.nimFile
-    b.endTree()
-    b.endTree()
-
-  b.endTree()  # stmts
-
-proc commandDeps*(conf: ConfigRef) =
-  ## Main entry point for `nim deps`
-  when not defined(nimKochBootstrap):
-    let nifler = findNifler()
-    if nifler.len == 0:
-      rawMessage(conf, errGenerated, "nifler tool not found. Install nimony or add nifler to PATH.")
-      return
-
-    let projectFile = conf.projectFull.string
-    if not fileExists(projectFile):
-      rawMessage(conf, errGenerated, "project file not found: " & projectFile)
-      return
-
-    # Create nimcache directory
-    createDir(getNimcacheDir(conf).string)
-
-    var c = DepContext(
-      config: conf,
-      nifler: nifler,
-      nodes: @[],
-      processedModules: initTable[string, int](),
-      includeStack: @[]
-    )
-
-    # Create root node for main project file
-    let rootPair = c.toPair(projectFile)
-    let rootNode = Node(files: @[rootPair], id: 0)
-    c.nodes.add rootNode
-    c.processedModules[rootPair.modname] = 0
-
-    # Process dependencies
-    traverseDeps(c, rootPair, rootNode)
-
-    # Generate build file
-    let buildFile = generateBuildFile(c)
-    rawMessage(conf, hintSuccess, "generated: " & buildFile)
-    rawMessage(conf, hintSuccess, "run: nifmake run " & buildFile)
-  else:
-    rawMessage(conf, errGenerated, "nim deps not available in bootstrap build")
--- a/compiler/dfa.nim
+++ b/compiler/dfa.nim
@@ -22,9 +22,8 @@
 ## "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, lineinfos, renderer, aliasanalysis
+import ast, intsets, lineinfos, renderer, aliasanalysis
 import std/private/asciitables
-import std/intsets

 when defined(nimPreviewSlimSystem):
  import std/assertions
@@ -46,10 +45,10 @@ 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
@@ -181,6 +180,14 @@ 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
@@ -205,6 +212,7 @@ proc genAndOr(c: var Con; n: PNode) =
  #   fork lab1
  #   asgn dest, b
  # lab1:
+  #   join F1
  c.gen(n[1])
  forkT:
    c.gen(n[2])
@@ -315,7 +323,7 @@ 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)

@@ -371,7 +379,7 @@ 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.signatureLen and isOutParam(t[i]):
+    if t != nil and i < t.len 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:
@@ -381,6 +389,7 @@ 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:
@@ -439,8 +448,8 @@ proc gen(c: var Con; n: PNode) =
    genUse(c, n)
  of nkIfStmt, nkIfExpr: genIf(c, n)
  of nkWhenStmt:
-    # This is "when nimvm" node. Chose the second branch.
-    gen(c, n[1][0])
+    # This is "when nimvm" node. Chose the first branch.
+    gen(c, n[0][1])
  of nkCaseStmt: genCase(c, n)
  of nkWhileStmt: genWhile(c, n)
  of nkBlockExpr, nkBlockStmt: genBlock(c, n)
--- a/compiler/docgen.nim
+++ b/compiler/docgen.nim
@@ -15,16 +15,15 @@
 ## For corresponding users' documentation see [Nim DocGen Tools Guide].

 import
-  ast, options, msgs, idents,
+  ast, strutils, strtabs, algorithm, sequtils, options, msgs, os, idents,
  wordrecg, syntaxes, renderer, lexer,
  packages/docutils/[rst, rstidx, rstgen, dochelpers],
-  trees, types,
-  typesrenderer, lineinfos,
-  pathutils, nimpaths, renderverbatim, packages
+  json, xmltree, trees, types,
+  typesrenderer, astalgo, lineinfos, intsets,
+  pathutils, tables, nimpaths, renderverbatim, osproc, packages
 import packages/docutils/rstast except FileIndex, TLineInfo

-import std/[os, strutils, strtabs, algorithm, json, osproc, tables, intsets, xmltree, sequtils]
-from std/uri import encodeUrl
+from uri import encodeUrl
 from nodejs import findNodeJs

 when defined(nimPreviewSlimSystem):
@@ -115,7 +114,7 @@ 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, invalid)
+  result = d.nimToRstFid.getOrDefault(fileIndex, default = invalid)
  if result == invalid:
    let fname = toFullPath(d.conf, fileIndex)
    result = addFilename(d.sharedState, fname)
@@ -289,7 +288,7 @@ template declareClosures(currentFilename: AbsoluteFile, destFile: string) =
    let outDirPath: RelativeFile =
        presentationPath(conf, AbsoluteFile(basedir / targetRelPath))
          # use presentationPath because `..` path can be be mangled to `_._`
-    result = (string(conf.outDir / outDirPath), "")
+    result.targetPath = 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
@@ -830,8 +829,8 @@ proc getName(n: PNode): string =
  of nkAccQuoted:
    result = "`"
    for i in 0..<n.len: result.add(getName(n[i]))
-    result.add('`')
-  of nkOpenSymChoice, nkClosedSymChoice, nkOpenSym:
+    result = "`"
+  of nkOpenSymChoice, nkClosedSymChoice:
    result = getName(n[0])
  else:
    result = ""
@@ -849,7 +848,7 @@ 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, nkOpenSym:
+  of nkOpenSymChoice, nkClosedSymChoice:
    result = getNameIdent(cache, n[0])
  else:
    result = nil
@@ -863,7 +862,7 @@ 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, nkOpenSym:
+  of nkOpenSymChoice, nkClosedSymChoice:
    result = getRstName(n[0])
  else:
    result = nil
@@ -1000,9 +999,8 @@ 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 = LangSymbol(name: baseName.nimIdentNormalize,
-      symKind: k.toHumanStr
-  )
+  result.name = baseName.nimIdentNormalize
+  result.symKind = k.toHumanStr
  if k in routineKinds:
    var
      paramTypes: seq[string] = @[]
@@ -1031,7 +1029,7 @@ proc toLangSymbol(k: TSymKind, n: PNode, baseName: string): LangSymbol =
    if genNode != nil:
      var literal = ""
      var r: TSrcGen = initTokRender(genNode, {renderNoBody, renderNoComments,
-        renderNoPragmas, renderNoProcDefs, renderExpandUsing, renderNoPostfix})
+        renderNoPragmas, renderNoProcDefs, renderExpandUsing})
      var kind = tkEof
      while true:
        getNextTok(r, kind, literal)
@@ -1059,7 +1057,7 @@ proc genItem(d: PDoc, n, nameNode: PNode, k: TSymKind, docFlags: DocFlags, nonEx

  # Obtain the plain rendered string for hyperlink titles.
  var r: TSrcGen = initTokRender(n, {renderNoBody, renderNoComments, renderDocComments,
-    renderNoPragmas, renderNoProcDefs, renderExpandUsing, renderNoPostfix})
+    renderNoPragmas, renderNoProcDefs, renderExpandUsing})
  while true:
    getNextTok(r, kind, literal)
    if kind == tkEof:
@@ -1086,9 +1084,6 @@ 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(
@@ -1099,10 +1094,10 @@ proc genItem(d: PDoc, n, nameNode: PNode, k: TSymKind, docFlags: DocFlags, nonEx
               priority = symbolPriority(k), info = lineinfo,
               module = addRstFileIndex(d, FileIndex d.module.position))

-  var renderFlags = {renderNoBody, renderNoComments, renderDocComments,
-    renderSyms, renderExpandUsing, renderNoPostfix}
-  if nonExports:
-    renderFlags.incl renderNonExportedFields
+  let renderFlags =
+    if nonExports: {renderNoBody, renderNoComments, renderDocComments, renderSyms,
+      renderExpandUsing, renderNonExportedFields}
+    else: {renderNoBody, renderNoComments, renderDocComments, renderSyms, renderExpandUsing}
  nodeToHighlightedHtml(d, n, result, renderFlags, symbolOrIdEnc)

  let seeSrc = genSeeSrc(d, toFullPath(d.conf, n.info), n.info.line.int)
@@ -1125,19 +1120,18 @@ 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 symNameNode.kind == nkSym:
+  if k in routineKinds and nameNode.kind == nkSym:
    let att = attachToType(d, nameNode.sym)
    if att != nil:
      attype = esc(d.target, att.name.s)
-  elif k == skType and symNameNode.kind == nkSym and
-      symNameNode.sym.typ.kind in {tyEnum, tyBool}:
-    let etyp = symNameNode.sym.typ
+  elif k == skType and nameNode.kind == nkSym and nameNode.sym.typ.kind in {tyEnum, tyBool}:
+    let etyp = nameNode.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 = symNameNode.sym.name.s & '.' & plain,
+                   term = plain, linkTitle = nameNode.sym.name.s & '.' & plain,
                   linkDesc = xmltree.escape(getPlainDocstring(e).docstringSummary),
                   line = n.info.line.int)

@@ -1158,8 +1152,8 @@ 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 symNameNode.kind == nkSym:
-    d.types.strTableAdd symNameNode.sym
+  if k == skType and nameNode.kind == nkSym:
+    d.types.strTableAdd nameNode.sym

 proc genJsonItem(d: PDoc, n, nameNode: PNode, k: TSymKind, nonExports = false): JsonItem =
  if not isVisible(d, nameNode): return
@@ -1167,14 +1161,12 @@ 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, renderNoPostfix}
+    renderFlags = {renderNoBody, renderNoComments, renderDocComments, renderExpandUsing}
  if nonExports:
    renderFlags.incl renderNonExportedFields
  r = initTokRender(n, renderFlags)
-  result = JsonItem(json: %{ "name": %name, "type": %($k), "line": %n.info.line.int,
+  result.json = %{ "name": %name, "type": %($k), "line": %n.info.line.int,
                   "col": %n.info.col}
-  )
  if comm != nil:
    result.rst = comm
    result.rstField = "description"
@@ -1206,7 +1198,8 @@ proc genJsonItem(d: PDoc, n, nameNode: PNode, k: TSymKind, nonExports = false):
        var param = %{"name": %($genericParam)}
        if genericParam.sym.typ.len > 0:
          param["types"] = newJArray()
-          param["types"] = %($genericParam.sym.typ.elementType)
+        for kind in genericParam.sym.typ:
+          param["types"].add %($kind)
        result.json["signature"]["genericParams"].add param
  if optGenIndex in d.conf.globalOptions:
    genItem(d, n, nameNode, k, kForceExport)
@@ -1407,13 +1400,9 @@ proc generateDoc*(d: PDoc, n, orig: PNode, config: ConfigRef, docFlags: DocFlags
  of nkExportStmt:
    for it in n:
      if it.kind == nkSym:
-        if d.module != nil and d.module == it.sym.owner:  # in current module
-          # bug #23051; don't generate documentation for exported symbols again
-          if sfExported notin it.sym.flags:
-            generateDoc(d, it.sym.ast, orig, config, kForceExport)
-          # else it's to be handled in `of XxxSection` branch
+        if d.module != nil and d.module == it.sym.owner:
+          generateDoc(d, it.sym.ast, orig, config, kForceExport)
        elif it.sym.ast != nil:
-          # only export symbols in imported modules, not in current module
          exportSym(d, it.sym)
  of nkExportExceptStmt: discard "transformed into nkExportStmt by semExportExcept"
  of nkFromStmt, nkImportExceptStmt: traceDeps(d, n[0])
@@ -1816,7 +1805,7 @@ proc writeOutputJson*(d: PDoc, useWarning = false) =
    "moduleDescription": modDesc,
    "entries": d.jEntriesFinal}
  if optStdout in d.conf.globalOptions:
-    writeLine(stdout, $content)
+    write(stdout, $content)
  else:
    let dir = d.destFile.splitFile.dir
    createDir(dir)
@@ -1892,9 +1881,6 @@ proc commandJson*(cache: IdentCache, conf: ConfigRef) =
  else:
    #echo getOutFile(gProjectFull, JsonExt)
    let filename = getOutFile(conf, RelativeFile conf.projectName, JsonExt)
-    conf.outFile = filename.relativeTo(conf.outDir)
-    let dir = filename.splitFile.dir
-    createDir(dir)
    try:
      writeFile(filename, content)
    except IOError:
@@ -1915,10 +1901,8 @@ proc commandTags*(cache: IdentCache, conf: ConfigRef) =
  if optStdout in d.conf.globalOptions:
    write(stdout, content)
  else:
+    #echo getOutFile(gProjectFull, TagsExt)
    let filename = getOutFile(conf, RelativeFile conf.projectName, TagsExt)
-    conf.outFile = filename.relativeTo(conf.outDir)
-    let dir = filename.splitFile.dir
-    createDir(dir)
    try:
      writeFile(filename, content)
    except IOError:
--- a/compiler/enumtostr.nim
+++ b/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, idgen, t.owner)
+  result.typ = newType(tyProc, nextTypeId idgen, t.owner)
  result.typ.n = newNodeI(nkFormalParams, info)
  rawAddSon(result.typ, res.typ)
  result.typ.n.add newNodeI(nkEffectList, info)
@@ -33,10 +33,6 @@ proc genEnumToStrProc*(t: PType; info: TLineInfo; g: ModuleGraph; idgen: IdGener
    caseStmt.add newTree(nkOfBranch, newIntTypeNode(field.position, t),
      newTree(nkStmtList, newTree(nkFastAsgn, newSymNode(res), newStrNode(val, info))))
    #newIntTypeNode(nkIntLit, field.position, t)
-  # safety branch for invalid data:
-  caseStmt.add newTree(nkElse,
-    newTree(nkStmtList, newTree(nkFastAsgn, newSymNode(res),
-      newStrNode("", info))))

  body.add(caseStmt)

@@ -47,7 +43,8 @@ proc genEnumToStrProc*(t: PType; info: TLineInfo; g: ModuleGraph; idgen: IdGener
  n[bodyPos] = body
  n[resultPos] = newSymNode(res)
  result.ast = n
-  incl result.flagsImpl, {sfFromGeneric, sfNeverRaises}
+  incl result.flags, sfFromGeneric
+  incl result.flags, sfNeverRaises

 proc searchObjCaseImpl(obj: PNode; field: PSym): PNode =
  case obj.kind
@@ -66,8 +63,8 @@ proc searchObjCaseImpl(obj: PNode; field: PSym): PNode =

 proc searchObjCase(t: PType; field: PSym): PNode =
  result = searchObjCaseImpl(t.n, field)
-  if result == nil and t.baseClass != nil:
-    result = searchObjCase(t.baseClass.skipTypes({tyAlias, tyGenericInst, tyRef, tyPtr}), field)
+  if result == nil and t.len > 0:
+    result = searchObjCase(t[0].skipTypes({tyAlias, tyGenericInst, tyRef, tyPtr}), field)
  doAssert result != nil

 proc genCaseObjDiscMapping*(t: PType; field: PSym; info: TLineInfo; g: ModuleGraph; idgen: IdGenerator): PSym =
@@ -79,7 +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, idgen, t.owner)
+  result.typ = newType(tyProc, nextTypeId idgen, t.owner)
  result.typ.n = newNodeI(nkFormalParams, info)
  rawAddSon(result.typ, res.typ)
  result.typ.n.add newNodeI(nkEffectList, info)
@@ -109,4 +106,5 @@ proc genCaseObjDiscMapping*(t: PType; field: PSym; info: TLineInfo; g: ModuleGra
  n[bodyPos] = body
  n[resultPos] = newSymNode(res)
  result.ast = n
-  incl result.flagsImpl, {sfFromGeneric, sfNeverRaises}
+  incl result.flags, sfFromGeneric
+  incl result.flags, sfNeverRaises
--- a/compiler/errorhandling.nim
+++ b/compiler/errorhandling.nim
@@ -10,8 +10,7 @@
 ## This module contains support code for new-styled error
 ## handling via an `nkError` node kind.

-import ast, renderer, options, types
-import std/strutils
+import ast, renderer, options, strutils, types

 when defined(nimPreviewSlimSystem):
  import std/assertions
@@ -41,8 +40,7 @@ proc newError*(wrongNode: PNode; k: ErrorKind; args: varargs[PNode]): PNode =
  let innerError = errorSubNode(wrongNode)
  if innerError != nil:
    return innerError
-  var idgen = idGeneratorForPackage(-1'i32)
-  result = newNodeIT(nkError, wrongNode.info, newType(tyError, idgen, nil))
+  result = newNodeIT(nkError, wrongNode.info, newType(tyError, ItemId(module: -1, item: -1), nil))
  result.add wrongNode
  result.add newIntNode(nkIntLit, ord(k))
  for a in args: result.add a
@@ -52,8 +50,7 @@ proc newError*(wrongNode: PNode; msg: string): PNode =
  let innerError = errorSubNode(wrongNode)
  if innerError != nil:
    return innerError
-  var idgen = idGeneratorForPackage(-1'i32)
-  result = newNodeIT(nkError, wrongNode.info, newType(tyError, idgen, nil))
+  result = newNodeIT(nkError, wrongNode.info, newType(tyError, ItemId(module: -1, item: -1), nil))
  result.add wrongNode
  result.add newIntNode(nkIntLit, ord(CustomError))
  result.add newStrNode(msg, wrongNode.info)
--- a/compiler/evalffi.nim
+++ b/compiler/evalffi.nim
@@ -9,12 +9,10 @@

 ## This file implements the FFI part of the evaluator for Nim code.

-import ast, types, options, msgs, lineinfos
-from std/os import getAppFilename
+import ast, types, options, tables, dynlib, msgs, lineinfos
+from os import getAppFilename
 import libffi/libffi

-import std/[tables, dynlib]
-
 when defined(windows):
  const libcDll = "msvcrt.dll"
 elif defined(linux):
@@ -99,7 +97,7 @@ 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.skipModifier)
+    result = mapType(conf, t[0])
  else:
    result = nil
  # too risky:
@@ -126,16 +124,16 @@ 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.elementType)
+      result = sizeof(pointer) + packSize(conf, v[0], typ.lastSon)
  of tyDistinct, tyGenericInst, tyAlias, tySink:
-    result = packSize(conf, v, typ.skipModifier)
+    result = packSize(conf, v, typ[0])
  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.elementType)
+      result = v.len * packSize(conf, v[0], typ[1])
    else:
      result = 0
  else:
@@ -234,19 +232,19 @@ 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.elementType, res +! sizeof(pointer))
+      pack(conf, v[0], typ.lastSon, res +! sizeof(pointer))
      dec packRecCheck
      awr(pointer, res +! sizeof(pointer))
  of tyArray:
-    let baseSize = getSize(conf, typ.elementType)
+    let baseSize = getSize(conf, typ[1])
    for i in 0..<v.len:
-      pack(conf, v[i], typ.elementType, res +! i * baseSize)
+      pack(conf, v[i], typ[1], res +! i * baseSize)
  of tyObject, tyTuple:
    packObject(conf, v, typ, res)
  of tyNil:
    discard
  of tyDistinct, tyGenericInst, tyAlias, tySink:
-    pack(conf, v, typ.skipModifier, res)
+    pack(conf, v, typ[0], res)
  else:
    globalError(conf, v.info, "cannot map value to FFI " & typeToString(v.typ))

@@ -304,9 +302,9 @@ proc unpackArray(conf: ConfigRef, x: pointer, typ: PType, n: PNode): PNode =
    result = n
    if result.kind != nkBracket:
      globalError(conf, n.info, "cannot map value from FFI")
-  let baseSize = getSize(conf, typ.elementType)
+  let baseSize = getSize(conf, typ[1])
  for i in 0..<result.len:
-    result[i] = unpack(conf, x +! i * baseSize, typ.elementType, result[i])
+    result[i] = unpack(conf, x +! i * baseSize, typ[1], result[i])

 proc canonNodeKind(k: TNodeKind): TNodeKind =
  case k
@@ -387,7 +385,7 @@ 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.elementType, n[0])
+      n[0] = unpack(conf, p, typ.lastSon, n[0])
      result = n
    else:
      result = nil
@@ -405,7 +403,7 @@ proc unpack(conf: ConfigRef, x: pointer, typ: PType, n: PNode): PNode =
  of tyNil:
    setNil()
  of tyDistinct, tyGenericInst, tyAlias, tySink:
-    result = unpack(conf, x, typ.skipModifier, n)
+    result = unpack(conf, x, typ.lastSon, n)
  else:
    # XXX what to do with 'array' here?
    result = nil
@@ -434,7 +432,7 @@ proc fficast*(conf: ConfigRef, x: PNode, destTyp: PType): PNode =
 proc callForeignFunction*(conf: ConfigRef, call: PNode): PNode =
  internalAssert conf, call[0].kind == nkPtrLit

-  var cif: TCif = default(TCif)
+  var cif: TCif
  var sig: ParamList = default(ParamList)
  # use the arguments' types for varargs support:
  for i in 1..<call.len:
@@ -444,7 +442,7 @@ 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.returnType), sig) != OK:
+              mapType(conf, typ[0]), sig) != OK:
    globalError(conf, call.info, "error in FFI call")

  var args: ArgList = default(ArgList)
@@ -453,15 +451,15 @@ proc callForeignFunction*(conf: ConfigRef, call: PNode): PNode =
    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.returnType): pointer(nil)
-               else: alloc(getSize(conf, typ.returnType).int)
+  let retVal = if isEmptyType(typ[0]): pointer(nil)
+               else: alloc(getSize(conf, typ[0]).int)

  libffi.call(cif, fn, retVal, args)

  if retVal.isNil:
    result = newNode(nkEmpty)
  else:
-    result = unpack(conf, retVal, typ.returnType, nil)
+    result = unpack(conf, retVal, typ[0], nil)
    result.info = call.info

  if retVal != nil: dealloc retVal
@@ -474,7 +472,7 @@ proc callForeignFunction*(conf: ConfigRef, fn: PNode, fntyp: PType,
                          info: TLineInfo): PNode =
  internalAssert conf, fn.kind == nkPtrLit

-  var cif: TCif = default(TCif)
+  var cif: TCif
  var sig: ParamList = default(ParamList)
  for i in 0..len-1:
    var aTyp = args[i+start].typ
--- a/compiler/evaltempl.nim
+++ b/compiler/evaltempl.nim
@@ -9,16 +9,16 @@

 ## Template evaluation engine. Now hygienic.

-import options, ast, astalgo, msgs, renderer, lineinfos, idents, trees
-import std/strutils
+import
+  strutils, options, ast, astalgo, msgs, renderer, lineinfos, idents, trees

 type
  TemplCtx = object
    owner, genSymOwner: PSym
    instLines: bool   # use the instantiation lines numbers
    isDeclarative: bool
-    mapping: SymMapping # every gensym'ed symbol needs to be mapped to some
-                        # new symbol
+    mapping: TIdTable # every gensym'ed symbol needs to be mapped to some
+                      # new symbol
    config: ConfigRef
    ic: IdentCache
    instID: int
@@ -33,19 +33,6 @@ 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)

@@ -57,19 +44,18 @@ 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.signatureLen + s.position - 1]
+        handleParam actual[s.owner.typ.len + s.position - 1]
      else:
        internalAssert c.config, sfGenSym in s.flags or s.kind == skType
-        var x = idTableGet(c.mapping, s)
+        var x = PSym(idTableGet(c.mapping, s))
        if x == nil:
          x = copySym(s, c.idgen)
          # sem'check needs to set the owner properly later, see bug #9476
-          setOwner(x, nil) # c.genSymOwner
+          x.owner = 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:
@@ -130,7 +116,7 @@ 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.paramsLen
+    expectedRegularParams = s.typ.len-1
    givenRegularParams = totalParams - genericParams
  if givenRegularParams < 0: givenRegularParams = 0

@@ -196,14 +182,14 @@ proc evalTemplate*(n: PNode, tmpl, genSymOwner: PSym;

  # replace each param by the corresponding node:
  var args = evalTemplateArgs(n, tmpl, conf, fromHlo)
-  var ctx = TemplCtx(owner: tmpl,
-    genSymOwner: genSymOwner,
-    config: conf,
-    ic: ic,
-    mapping: initSymMapping(),
-    instID: instID[],
-    idgen: idgen
-  )
+  var ctx: TemplCtx
+  ctx.owner = tmpl
+  ctx.genSymOwner = genSymOwner
+  ctx.config = conf
+  ctx.ic = ic
+  ctx.mapping = initIdTable()
+  ctx.instID = instID[]
+  ctx.idgen = idgen

  let body = tmpl.ast[bodyPos]
  #echo "instantion of ", renderTree(body, {renderIds})
--- a/compiler/expanddefaults.nim
+++ b/compiler/expanddefaults.nim
@@ -1,131 +0,0 @@
-#
-#
-#           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
--- a/compiler/extccomp.nim
+++ b/compiler/extccomp.nim
@@ -19,7 +19,7 @@ import std/[os, osproc, streams, sequtils, times, strtabs, json, jsonutils, suga
 import std / strutils except addf

 when defined(nimPreviewSlimSystem):
-  import std/[syncio, assertions]
+  import std/syncio

 import ../dist/checksums/src/checksums/sha1

@@ -33,7 +33,6 @@ type
    hasGnuAsm,                # CC's asm uses the absurd GNU assembler syntax
    hasDeclspec,              # CC has __declspec(X)
    hasAttribute,             # CC has __attribute__((X))
-    hasBuiltinUnreachable     # CC has __builtin_unreachable
  TInfoCCProps* = set[TInfoCCProp]
  TInfoCC* = tuple[
    name: string,        # the short name of the compiler
@@ -63,7 +62,7 @@ type

 # Configuration settings for various compilers.
 # When adding new compilers, the cmake sources could be a good reference:
-# https://cmake.org/gitweb?p=cmake.git;a=tree;f=Modules/Platform;
+# http://cmake.org/gitweb?p=cmake.git;a=tree;f=Modules/Platform;

 template compiler(name, settings: untyped): untyped =
  proc name: TInfoCC {.compileTime.} = settings
@@ -96,7 +95,7 @@ compiler gcc:
    produceAsm: gnuAsmListing,
    cppXsupport: "-std=gnu++17 -funsigned-char",
    props: {hasSwitchRange, hasComputedGoto, hasCpp, hasGcGuard, hasGnuAsm,
-            hasAttribute, hasBuiltinUnreachable})
+            hasAttribute})

 # GNU C and C++ Compiler
 compiler nintendoSwitchGCC:
@@ -123,7 +122,7 @@ compiler nintendoSwitchGCC:
    produceAsm: gnuAsmListing,
    cppXsupport: "-std=gnu++17 -funsigned-char",
    props: {hasSwitchRange, hasComputedGoto, hasCpp, hasGcGuard, hasGnuAsm,
-            hasAttribute, hasBuiltinUnreachable})
+            hasAttribute})

 # LLVM Frontend for GCC/G++
 compiler llvmGcc:
@@ -162,11 +161,7 @@ compiler vcc:
    linkerExe: "cl",
    linkTmpl: "$builddll$vccplatform /Fe$exefile $objfiles $buildgui /nologo $options",
    includeCmd: " /I",
-    # 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:",
+    linkDirCmd: " /LIBPATH:",
    linkLibCmd: " $1.lib",
    debug: " /RTC1 /Z7 ",
    pic: "",
@@ -176,22 +171,6 @@ 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"
@@ -257,8 +236,8 @@ compiler tcc:
    linkerExe: "tcc",
    linkTmpl: "-o $exefile $options $buildgui $builddll $objfiles",
    includeCmd: " -I",
-    linkDirCmd: " -L",
-    linkLibCmd: " -l$1",
+    linkDirCmd: "", # XXX: not supported yet
+    linkLibCmd: "", # XXX: not supported yet
    debug: " -g ",
    pic: "",
    asmStmtFrmt: "asm($1);$n",
@@ -305,9 +284,7 @@ const
    envcc(),
    icl(),
    icc(),
-    clangcl(),
-    hipcc(),
-    nvcc()]
+    clangcl()]

  hExt* = ".h"

@@ -341,7 +318,7 @@ proc getConfigVar(conf: ConfigRef; c: TSystemCC, suffix: string): string =
  var fullSuffix = suffix
  case conf.backend
  of backendCpp, backendJs, backendObjc: fullSuffix = "." & $conf.backend & suffix
-  of backendC, backendNif: discard
+  of backendC: discard
  of backendInvalid:
    # during parsing of cfg files; we don't know the backend yet, no point in
    # guessing wrong thing
@@ -474,11 +451,6 @@ proc noAbsolutePaths(conf: ConfigRef): bool {.inline.} =
 proc cFileSpecificOptions(conf: ConfigRef; nimname, fullNimFile: string): string =
  result = conf.compileOptions

-  if (conf.cCompiler == ccGcc or conf.cCompiler == ccCLang) and
-       conf.selectedGC == gcRefc:
-    # bug #10625
-    addOpt(result, "-fno-omit-frame-pointer")
-
  for option in conf.compileOptionsCmd:
    if strutils.find(result, option, 0) < 0:
      addOpt(result, option)
@@ -786,7 +758,7 @@ 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
-    # https://www.debuginfo.com/articles/debuginfomatch.html#pdbfiles
+    # http://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"
@@ -810,59 +782,6 @@ template tryExceptOSErrorMessage(conf: ConfigRef; errorPrefix: string = "", body
        (ose.msg & " " & $ose.errorCode))
    raise

-proc createMacAppBundle(conf: ConfigRef; exefile: AbsoluteFile) =
-  let (dir, name, _) = splitFile(exefile.string)
-  let appBundleName = name & ".app"
-  let appBundlePath = dir / appBundleName
-  let contentsPath = appBundlePath / "Contents"
-  let macosPath = contentsPath / "MacOS"
-
-  createDir(macosPath)
-
-  let bundleExePath = macosPath / name
-  copyFileWithPermissions(exefile.string, bundleExePath)
-
-  let infoPlistPath = contentsPath / "Info.plist"
-
-  proc xmlEscape(s: string): string =
-    result = newStringOfCap(s.len)
-    for c in items(s):
-      case c:
-      of '<': result.add("&lt;")
-      of '>': result.add("&gt;")
-      of '&': result.add("&amp;")
-      of '"': result.add("&quot;")
-      of '\'': result.add("&apos;")
-      else:
-        if ord(c) < 32:
-          result.add("&#" & $ord(c) & ';')
-        else:
-          result.add(c)
-
-  let escapedName = xmlEscape(name)
-  let infoPlistContent = """<?xml version="1.0" encoding="UTF-8"?>
-<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
-<plist version="1.0">
-<dict>
-  <key>CFBundleExecutable</key>
-  <string>$1</string>
-  <key>CFBundleIdentifier</key>
-  <string>com.nim.$1</string>
-  <key>CFBundleName</key>
-  <string>$1</string>
-  <key>CFBundlePackageType</key>
-  <string>APPL</string>
-  <key>LSUIElement</key>
-  <string>1</string>
-</dict>
-</plist>""" % [escapedName]
-
-  writeFile(infoPlistPath, infoPlistContent)
-
-  removeFile(exefile.string)
-
-  rawMessage(conf, hintUserRaw, "Created Mac app bundle: " & appBundlePath)
-
 proc getExtraCmds(conf: ConfigRef; output: AbsoluteFile): seq[string] =
  result = @[]
  when defined(macosx):
@@ -1047,10 +966,6 @@ proc callCCompiler*(conf: ConfigRef) =
        preventLinkCmdMaxCmdLen(conf, linkCmd)
        for cmd in extraCmds:
          execExternalProgram(conf, cmd, hintExecuting)
-        # create Mac app bundle for GUI apps on macOS
-        when defined(macosx):
-          if conf.globalOptions * {optGenGuiApp, optGenDynLib, optGenStaticLib} == {optGenGuiApp}:
-            createMacAppBundle(conf, mainOutput)
  else:
    linkCmd = ""
  if optGenScript in conf.globalOptions:
@@ -1066,11 +981,10 @@ proc jsonBuildInstructionsFile*(conf: ConfigRef): AbsoluteFile =
  # works out of the box with `hashMainCompilationParams`.
  result = getNimcacheDir(conf) / conf.outFile.changeFileExt("json")

-const cacheVersion = "D20240927T193831" # update when `BuildCache` spec changes
+const cacheVersion = "D20210525T193831" # update when `BuildCache` spec changes
 type BuildCache = object
  cacheVersion: string
  outputFile: string
-  outputLastModificationTime: string
  compile: seq[(string, string)]
  link: seq[string]
  linkcmd: string
@@ -1084,7 +998,7 @@ type BuildCache = object
  depfiles: seq[(string, string)]
  nimexe: string

-proc writeJsonBuildInstructions*(conf: ConfigRef; deps: StringTableRef) =
+proc writeJsonBuildInstructions*(conf: ConfigRef) =
  var linkFiles = collect(for it in conf.externalToLink:
    var it = it
    if conf.noAbsolutePaths: it = it.extractFilename
@@ -1105,17 +1019,11 @@ proc writeJsonBuildInstructions*(conf: ConfigRef; deps: StringTableRef) =
    currentDir: getCurrentDir())
  if optRun in conf.globalOptions or isDefined(conf, "nimBetterRun"):
    bcache.cmdline = conf.commandLine
-    for it in conf.m.fileInfos:
+    bcache.depfiles = collect(for it in conf.m.fileInfos:
      let path = it.fullPath.string
      if isAbsolute(path): # TODO: else?
-        if path in deps:
-          bcache.depfiles.add (path, deps[path])
-        else: # backup for configs etc.
-          bcache.depfiles.add (path, $secureHashFile(path))
-
+        (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)

@@ -1136,8 +1044,6 @@ 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 = default(BuildCache)
@@ -1154,7 +1060,7 @@ proc runJsonBuildInstructions*(conf: ConfigRef; jsonFile: AbsoluteFile) =
      "jsonscript command outputFile '$1' must match '$2' which was specified during --compileOnly, see \"outputFile\" entry in '$3' " %
      [outputCurrent, output, jsonFile.string])
  var cmds: TStringSeq = default(TStringSeq)
-  var prettyCmds: 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
--- a/compiler/filter_tmpl.nim
+++ b/compiler/filter_tmpl.nim
@@ -10,11 +10,9 @@
 # This module implements Nim's standard template filter.

 import
-  llstream, ast, msgs, options,
+  llstream, strutils, ast, msgs, options,
  filters, lineinfos, pathutils

-import std/strutils
-
 type
  TParseState = enum
    psDirective, psTempl
--- a/compiler/filters.nim
+++ b/compiler/filters.nim
@@ -10,11 +10,9 @@
 # This module implements Nim's simple filters and helpers for filters.

 import
-  llstream, idents, ast, msgs, options,
+  llstream, idents, strutils, 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}))
--- a/compiler/gorgeimpl.nim
+++ b/compiler/gorgeimpl.nim
@@ -9,9 +9,8 @@

 ## Module that implements ``gorge`` for the compiler.

-import msgs, options, lineinfos, pathutils
-
-import std/[os, osproc, streams]
+import msgs, os, osproc, streams, options,
+  lineinfos, pathutils

 when defined(nimPreviewSlimSystem):
  import std/syncio
--- a/compiler/guards.nim
+++ b/compiler/guards.nim
@@ -870,7 +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 std/macros
+import macros

 macro `=~`(x: PNode, pat: untyped): bool =
  proc m(x, pat, conds: NimNode) =
@@ -1063,7 +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:
@@ -1098,8 +1098,8 @@ proc addFactLt*(m: var TModel; a, b: PNode) =
  addFactLe(m, a, bb)

 proc settype(n: PNode): PType =
-  var idgen = idGeneratorForPackage(-1'i32)
-  result = newType(tySet, idgen, n.typ.owner)
+  result = newType(tySet, ItemId(module: -1, item: -1), n.typ.owner)
+  var idgen: IdGenerator = nil
  addSonSkipIntLit(result, n.typ, idgen)

 proc buildOf(it, loc: PNode; o: Operators): PNode =
@@ -1165,12 +1165,8 @@ 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
--- a/compiler/hlo.nim
+++ b/compiler/hlo.nim
@@ -10,7 +10,7 @@
 # This include implements the high level optimization pass.
 # included from sem.nim

-proc hlo(c: PContext, n: PNode, loopDetector: int): PNode
+proc hlo(c: PContext, n: PNode): PNode

 proc evalPattern(c: PContext, n, orig: PNode): PNode =
  internalAssert c.config, n.kind == nkCall and n[0].kind == nkSym
@@ -61,11 +61,10 @@ proc applyPatterns(c: PContext, n: PNode): PNode =
        # activate this pattern again:
        c.patterns[i] = pattern

-proc hlo(c: PContext, n: PNode, loopDetector: int): PNode =
+proc hlo(c: PContext, n: PNode): PNode =
+  inc(c.hloLoopDetector)
  # simply stop and do not perform any further transformations:
-  if loopDetector > 300:
-    message(c.config, n.info, warnUser, "term rewrite macro instantiation too nested")
-    return n
+  if c.hloLoopDetector > 300: return n
  case n.kind
  of nkMacroDef, nkTemplateDef, procDefs:
    # already processed (special cases in semstmts.nim)
@@ -81,7 +80,7 @@ proc hlo(c: PContext, n: PNode, loopDetector: int): PNode =
      # no optimization applied, try subtrees:
      for i in 0..<result.safeLen:
        let a = result[i]
-        let h = hlo(c, a, loopDetector)
+        let h = hlo(c, a)
        if h != a: result[i] = h
    else:
      # perform type checking, so that the replacement still fits:
@@ -91,15 +90,17 @@ proc hlo(c: PContext, n: PNode, loopDetector: int): PNode =
        result = fitNode(c, n.typ, result, n.info)
      # optimization has been applied so check again:
      result = commonOptimizations(c.graph, c.idgen, c.module, result)
-      result = hlo(c, result, loopDetector + 1)
+      result = hlo(c, result)
      result = commonOptimizations(c.graph, c.idgen, c.module, result)

 proc hloBody(c: PContext, n: PNode): PNode =
  # fast exit:
  if c.patterns.len == 0 or optTrMacros notin c.config.options: return n
-  result = hlo(c, n, 0)
+  c.hloLoopDetector = 0
+  result = hlo(c, n)

 proc hloStmt(c: PContext, n: PNode): PNode =
  # fast exit:
  if c.patterns.len == 0 or optTrMacros notin c.config.options: return n
-  result = hlo(c, n, 0)
+  c.hloLoopDetector = 0
+  result = hlo(c, n)
--- a/compiler/ic/bitabs.nim
+++ b/compiler/ic/bitabs.nim
@@ -1,8 +1,7 @@
 ## A BiTable is a table that can be seen as an optimized pair
 ## of `(Table[LitId, Val], Table[Val, LitId])`.

-import std/hashes
-import rodfiles
+import hashes, rodfiles

 when defined(nimPreviewSlimSystem):
  import std/assertions
@@ -36,7 +35,9 @@ proc mustRehash(length, counter: int): bool {.inline.} =
  result = (length * 2 < counter * 3) or (length - counter < 4)

 const
-  idStart = 1
+  idStart = 256 ##
+  ## Ids do not start with 0 but with this value. The IR needs it.
+  ## TODO: explain why

 template idToIdx(x: LitId): int = x.int - idStart

@@ -119,12 +120,6 @@ 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]
--- a/compiler/ic/cbackend.nim
+++ b/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
@@ -37,10 +37,11 @@ proc setupBackendModule(g: ModuleGraph; m: var LoadedModule) =
  if g.backend == nil:
    g.backend = cgendata.newModuleList(g)
  assert g.backend != nil
-  var bmod = cgen.newModule(BModuleList(g.backend), m.module, g.config, idgenFromLoadedModule(m))
+  var bmod = cgen.newModule(BModuleList(g.backend), m.module, g.config)
+  bmod.idgen = idgenFromLoadedModule(m)

 proc generateCodeForModule(g: ModuleGraph; m: var LoadedModule; alive: var AliveSyms) =
-  var bmod = BModuleList(g.backend).mods[m.module.position]
+  var bmod = BModuleList(g.backend).modules[m.module.position]
  assert bmod != nil
  bmod.flags.incl useAliveDataFromDce
  bmod.alive = move alive[m.module.position]
@@ -49,9 +50,10 @@ 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)

-  finalCodegenActions(g, bmod, newNodeI(nkStmtList, m.module.info))
-  for disp in getDispatchers(g):
-    genProcLvl3(bmod, disp)
+  let disps = finalCodegenActions(g, bmod, newNodeI(nkStmtList, m.module.info))
+  if disps != nil:
+    for disp in disps:
+      genProcAux(bmod, disp.sym)
  m.fromDisk.backendFlags = cgen.whichInitProcs(bmod)

 proc replayTypeInfo(g: ModuleGraph; m: var LoadedModule; origin: FileIndex) =
@@ -145,12 +147,12 @@ proc generateCode*(g: ModuleGraph) =
  var alive = computeAliveSyms(g.packed, g.config)

  when false:
-    for i in 0..<len(g.packed):
+    for i in 0..high(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..<len(g.packed):
+  for i in 0..high(g.packed):
    # case statement here to enforce exhaustive checks.
    case g.packed[i].status
    of undefined:
@@ -172,7 +174,7 @@ 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..<len(g.packed):
+  for i in 0..high(g.packed):
    if i != mainModuleIdx:
      genPackedModule(g, i, alive)
  if mainModuleIdx >= 0:
--- a/compiler/ic/dce.nim
+++ b/compiler/ic/dce.nim
@@ -109,13 +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, tree[n].soperand)
+    followLater(c, g, c.thisModule, n.operand)
  of nkModuleRef:
    let (n1, n2) = sons2(tree, n)
-    assert n1.kind == nkNone
-    assert n2.kind == nkNone
+    assert n1.kind == nkInt32Lit
+    assert n2.kind == nkInt32Lit
    let m = n1.litId
-    let item = tree[n2].soperand
+    let item = n2.operand
    let otherModule = toFileIndexCached(c.decoder, g, c.thisModule, m).int
    followLater(c, g, otherModule, item)
  of nkMacroDef, nkTemplateDef, nkTypeSection, nkTypeOfExpr,
@@ -131,7 +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 = tree[n.firstSon].soperand
+      let item = n.firstSon.operand
      if isExportedToC(c, g, item):
        # This symbol is alive and everything its body references.
        followLater(c, g, c.thisModule, item)
@@ -153,7 +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(len(g)-1, 0):
+  for i in countdown(high(g), 0):
    if g[i].status != undefined:
      c.thisModule = i
      for p in allNodes(g[i].fromDisk.topLevel):
--- a/compiler/ic/enum2nif.nim
+++ b/compiler/ic/enum2nif.nim
--- a/compiler/ic/ic.nim
+++ b/compiler/ic/ic.nim
@@ -7,17 +7,15 @@
 #    distribution, for details about the copyright.
 #

-import std/[hashes, tables, intsets, monotimes]
+import hashes, tables, intsets
 import packed_ast, bitabs, rodfiles
 import ".." / [ast, idents, lineinfos, msgs, ropes, options,
  pathutils, condsyms, packages, modulepaths]
 #import ".." / [renderer, astalgo]
-from std/os import removeFile, isAbsolute
+from os import removeFile, isAbsolute

 import ../../dist/checksums/src/checksums/sha1

-import iclineinfos
-
 when defined(nimPreviewSlimSystem):
  import std/[syncio, assertions, formatfloat]

@@ -43,28 +41,25 @@ 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)]
-    methodsPerGenericType*: seq[(PackedItemId, int, PackedItemId)]
+    methodsPerType*: seq[(PackedItemId, int, PackedItemId)]
    enumToStringProcs*: seq[(PackedItemId, PackedItemId)]
-    methodsPerType*: seq[(PackedItemId, PackedItemId)]
-    dispatchers*: seq[PackedItemId]

    emittedTypeInfo*: seq[string]
    backendFlags*: set[ModuleBackendFlag]

-    syms*: OrderedTable[int32, PackedSym]
-    types*: OrderedTable[int32, PackedType]
+    syms*: seq[PackedSym]
+    types*: seq[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

@@ -80,36 +75,37 @@ type
    symMarker*: IntSet #Table[ItemId, SymId]    # ItemId.item -> SymId
    config*: ConfigRef

-proc toString*(tree: PackedTree; pos: NodePos; m: PackedModule; nesting: int;
+proc toString*(tree: PackedTree; n: 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[pos].kind
-  of nkEmpty, nkNilLit, nkType: discard
+  case tree.nodes[pos].kind
+  of nkNone, nkEmpty, nkNilLit, nkType: discard
  of nkIdent, nkStrLit..nkTripleStrLit:
    result.add " "
-    result.add m.strings[LitId tree[pos].uoperand]
+    result.add m.strings[LitId tree.nodes[pos].operand]
  of nkSym:
    result.add " "
-    result.add m.strings[m.syms[tree[pos].soperand].name]
+    result.add m.strings[m.syms[tree.nodes[pos].operand].name]
  of directIntLit:
    result.add " "
-    result.addInt tree[pos].soperand
+    result.addInt tree.nodes[pos].operand
  of externSIntLit:
    result.add " "
-    result.addInt m.numbers[LitId tree[pos].uoperand]
+    result.addInt m.numbers[LitId tree.nodes[pos].operand]
  of externUIntLit:
    result.add " "
-    result.addInt cast[uint64](m.numbers[LitId tree[pos].uoperand])
+    result.addInt cast[uint64](m.numbers[LitId tree.nodes[pos].operand])
  of nkFloatLit..nkFloat128Lit:
    result.add " "
-    result.addFloat cast[BiggestFloat](m.numbers[LitId tree[pos].uoperand])
+    result.addFloat cast[BiggestFloat](m.numbers[LitId tree.nodes[pos].operand])
  else:
    result.add "(\n"
    for i in 1..(nesting+1)*2: result.add ' '
-    for child in sonsReadonly(tree, pos):
+    for child in sonsReadonly(tree, n):
      toString(tree, child, m, nesting + 1, result)
    result.add "\n"
    for i in 1..nesting*2: result.add ' '
@@ -235,14 +231,10 @@ 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))

@@ -261,8 +253,6 @@ 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)))
@@ -294,8 +284,7 @@ proc toLitId(x: BiggestInt; m: var PackedModule): LitId =
  result = getOrIncl(m.numbers, x)

 proc toPackedInfo(x: TLineInfo; c: var PackedEncoder; m: var PackedModule): PackedLineInfo =
-  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))
+  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
@@ -347,7 +336,7 @@ 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.item >= 0
+  assert s.itemId.module >= 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.
@@ -362,22 +351,16 @@ 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(id: t.uniqueId.item, kind: t.kind, flags: t.flags, callConv: t.callConv,
+    var p = PackedType(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)
-    if t.kind == tyProc and t.len > 0:
-      # if kind == tyProc, parameter types are stored in t.n
-      # and you can access them with `kits` iterator.
-      # return type is stored in t.sons[0].
-      p.types.add t[0].storeType(c, m)
-    else:
-      for kid in kids t:
-        p.types.add kid.storeType(c, m)
+    for kid in items t:
+      p.types.add kid.storeType(c, m)
    c.addMissing t.sym
    p.sym = t.sym.safeItemId(c, m)
    c.addMissing t.owner
@@ -389,9 +372,10 @@ 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 = PackedLib(kind: l.kind, generated: l.generated,
-    isOverridden: l.isOverridden, name: toLitId($l.name, m)
-  )
+  result.kind = l.kind
+  result.generated = l.generated
+  result.isOverridden = l.isOverridden
+  result.name = toLitId($l.name, m)
  storeNode(result, l, path)

 proc storeSym*(s: PSym; c: var PackedEncoder; m: var PackedModule): PackedItemId =
@@ -402,12 +386,12 @@ 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(id: s.itemId.item, kind: s.kind, flags: s.flags, info: s.info.toPackedInfo(c, m), magic: s.magic,
+    var p = PackedSym(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))

@@ -420,7 +404,7 @@ proc storeSym*(s: PSym; c: var PackedEncoder; m: var PackedModule): PackedItemId
      p.bitsize = s.bitsize
      p.alignment = s.alignment

-    p.externalName = toLitId(s.loc.snippet, m)
+    p.externalName = toLitId(s.loc.r, m)
    p.locFlags = s.loc.flags
    c.addMissing s.typ
    p.typ = s.typ.storeType(c, m)
@@ -437,59 +421,53 @@ 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)
-  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)
+  ir.nodes.add PackedNode(kind: nkModuleRef, operand: 3.int32, # spans 3 nodes in total
+                          typeId: storeTypeLater(n.typ, c, m), info: info)
+  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)

 proc toPackedNode*(n: PNode; ir: var PackedTree; c: var PackedEncoder; m: var PackedModule) =
  ## serialize a node into the tree
  if n == nil:
-    ir.addNode(kind = nkNilRodNode, operand = 1, info = NoLineInfo)
+    ir.nodes.add PackedNode(kind: nkNilRodNode, flags: {}, operand: 1)
    return
  let info = toPackedInfo(n.info, c, m)
  case n.kind
  of nkNone, nkEmpty, nkNilLit, nkType:
-    ir.addNode(kind = n.kind, flags = n.flags, operand = 0,
-               typeId = storeTypeLater(n.typ, c, m), info = info)
+    ir.nodes.add PackedNode(kind: n.kind, flags: n.flags, operand: 0,
+                            typeId: storeTypeLater(n.typ, c, m), info: info)
  of nkIdent:
-    ir.addNode(kind = n.kind, flags = n.flags,
-                operand = int32 getOrIncl(m.strings, n.ident.s),
-                typeId = storeTypeLater(n.typ, c, m), info = info)
+    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)
  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
-      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)
+      ir.nodes.add PackedNode(kind: nkSym, flags: n.flags, operand: id,
+                              typeId: storeTypeLater(n.typ, c, m), 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.addNode(kind = n.kind, flags = n.flags,
-               operand = int32 getOrIncl(m.numbers, n.intVal),
-               typeId = storeTypeLater(n.typ, c, m), info = info)
+    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)
  of nkStrLit..nkTripleStrLit:
-    ir.addNode(kind = n.kind, flags = n.flags,
-               operand = int32 getOrIncl(m.strings, n.strVal),
-               typeId = storeTypeLater(n.typ, c, m), info = info)
+    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)
  of nkFloatLit..nkFloat128Lit:
-    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)
+    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)
  else:
    let patchPos = ir.prepare(n.kind, n.flags,
                              storeTypeLater(n.typ, c, m), info)
@@ -514,8 +492,8 @@ 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.addNode(kind = nkEmpty, flags = {}, operand = 0,
-                 typeId = nilItemId, info = info)
+      ir.nodes.add PackedNode(kind: nkEmpty, flags: {}, operand: 0,
+                              typeId: nilItemId, info: info)
  ir.patch patchPos

 proc toPackedNodeIgnoreProcDefs(n: PNode, encoder: var PackedEncoder; m: var PackedModule) =
@@ -588,20 +566,6 @@ 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)
@@ -619,10 +583,6 @@ 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
@@ -630,48 +590,40 @@ proc loadRodFile*(filename: AbsoluteFile; m: var PackedModule; config: ConfigRef
  loadTabSection stringsSection, m.strings

  loadSeqSection checkSumsSection, m.includes
-  if config.cmd != cmdM and not includesIdentical(m, config):
+  if not includesIdentical(m, config):
    f.err = includeFileChanged

  loadSeqSection depsSection, m.imports

-  bench gloadBodies:
+  loadTabSection numbersSection, m.numbers

-    loadTabSection numbersSection, m.numbers
+  loadSeqSection exportsSection, m.exports
+  loadSeqSection hiddenSection, m.hidden
+  loadSeqSection reexportsSection, m.reexports

-    loadSeqSection exportsSection, m.exports
-    loadSeqSection hiddenSection, m.hidden
-    loadSeqSection reexportsSection, m.reexports
+  loadSeqSection compilerProcsSection, m.compilerProcs

-    loadSeqSection compilerProcsSection, m.compilerProcs
+  loadSeqSection trmacrosSection, m.trmacros

-    loadSeqSection trmacrosSection, m.trmacros
+  loadSeqSection convertersSection, m.converters
+  loadSeqSection methodsSection, m.methods
+  loadSeqSection pureEnumsSection, m.pureEnums

-    loadSeqSection convertersSection, m.converters
-    loadSeqSection methodsSection, m.methods
-    loadSeqSection pureEnumsSection, m.pureEnums
+  loadSeqSection toReplaySection, m.toReplay.nodes
+  loadSeqSection topLevelSection, m.topLevel.nodes
+  loadSeqSection bodiesSection, m.bodies.nodes
+  loadSeqSection symsSection, m.syms
+  loadSeqSection typesSection, m.types

-    loadTabSection toReplaySection, m.toReplay
-    loadTabSection topLevelSection, m.topLevel
+  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 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
+  f.loadSection backendFlagsSection
+  f.loadPrim m.backendFlags

  close(f)
  result = f.err
@@ -701,10 +653,6 @@ 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
@@ -724,29 +672,24 @@ proc saveRodFile*(filename: AbsoluteFile; encoder: var PackedEncoder; m: var Pac
  storeSeqSection methodsSection, m.methods
  storeSeqSection pureEnumsSection, m.pureEnums

-  storeTabSection toReplaySection, m.toReplay
-  storeTabSection topLevelSection, m.topLevel
+  storeSeqSection toReplaySection, m.toReplay.nodes
+  storeSeqSection topLevelSection, m.topLevel.nodes

-  storeTabSection bodiesSection, m.bodies
-  storeTableSection symsSection, m.syms
+  storeSeqSection bodiesSection, m.bodies.nodes
+  storeSeqSection symsSection, m.syms

-  storeTableSection typesSection, m.types
+  storeSeqSection typesSection, m.types

  storeSeqSection typeInstCacheSection, m.typeInstCache
  storeSeqSection procInstCacheSection, m.procInstCache
  storeSeqSection attachedOpsSection, m.attachedOps
-  storeSeqSection methodsPerGenericTypeSection, m.methodsPerGenericType
-  storeSeqSection enumToStringProcsSection, m.enumToStringProcs
  storeSeqSection methodsPerTypeSection, m.methodsPerType
-  storeSeqSection dispatchersSection, m.dispatchers
+  storeSeqSection enumToStringProcsSection, m.enumToStringProcs
  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:
@@ -781,36 +724,20 @@ type
    status*: ModuleStatus
    symsInit, typesInit, loadedButAliveSetChanged*: bool
    fromDisk*: PackedModule
-    syms: OrderedTable[int32, PSym] # indexed by itemId
-    types: OrderedTable[int32, PType]
+    syms: seq[PSym] # indexed by itemId
+    types: seq[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

-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
+  PackedModuleGraph* = seq[LoadedModule] # indexed by FileIndex

 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 f == LitId(0):
-    result = InvalidFileIdx
-  elif c.lastLit == f and c.lastModule == thisModule:
+  if c.lastLit == f and c.lastModule == thisModule:
    result = c.lastFile
  else:
    result = toFileIndex(f, g[thisModule].fromDisk, c.config)
@@ -821,9 +748,8 @@ 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}
-  let (fileId, line, col) = unpack(g[thisModule].fromDisk.man, x)
-  result = TLineInfo(line: line.uint16, col: col.int16,
-            fileIndex: toFileIndexCached(c, g, thisModule, fileId))
+  result = TLineInfo(line: x.line, col: x.col,
+            fileIndex: toFileIndexCached(c, g, thisModule, x.file))

 proc loadNodes*(c: var PackedDecoder; g: var PackedModuleGraph; thisModule: int;
                tree: PackedTree; n: NodePos): PNode =
@@ -837,14 +763,14 @@ proc loadNodes*(c: var PackedDecoder; g: var PackedModuleGraph; thisModule: int;
  result.flags = n.flags

  case k
-  of nkNone, nkEmpty, nkNilLit, nkType:
+  of 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[n].soperand))
-    if result.typ == nil:
-      result.typ = result.sym.typ
+    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
  of externIntLit:
    result.intVal = g[thisModule].fromDisk.numbers[n.litId]
  of nkStrLit..nkTripleStrLit:
@@ -853,12 +779,10 @@ 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 == nkNone
-    assert n2.kind == nkNone
+    assert n1.kind == nkInt32Lit
+    assert n2.kind == nkInt32Lit
    transitionNoneToSym(result)
-    result.sym = loadSym(c, g, thisModule, PackedItemId(module: n1.litId, item: tree[n2].soperand))
-    if result.typ == nil:
-      result.typ = result.sym.typ
+    result.sym = loadSym(c, g, thisModule, PackedItemId(module: n1.litId, item: tree.nodes[n2.int].operand))
  else:
    for n0 in sonsReadonly(tree, n):
      result.addAllowNil loadNodes(c, g, thisModule, tree, n0)
@@ -905,11 +829,11 @@ proc moduleIndex*(c: var PackedDecoder; g: var PackedModuleGraph; thisModule: in
 proc symHeaderFromPacked(c: var PackedDecoder; g: var PackedModuleGraph;
                         s: PackedSym; si, item: int32): PSym =
  result = PSym(itemId: ItemId(module: si, item: item),
-    kindImpl: s.kind, magicImpl: s.magic, flagsImpl: s.flags,
-    infoImpl: translateLineInfo(c, g, si, s.info),
-    optionsImpl: s.options,
-    positionImpl: if s.kind in {skForVar, skVar, skLet, skTemp}: 0 else: s.position,
-    offsetImpl: if s.kind in routineKinds: defaultOffset else: s.offset,
+    kind: s.kind, magic: s.magic, flags: s.flags,
+    info: translateLineInfo(c, g, si, s.info),
+    options: s.options,
+    position: if s.kind in {skForVar, skVar, skLet, skTemp}: 0 else: s.position,
+    offset: if s.kind in routineKinds: defaultOffset else: s.offset,
    disamb: s.disamb,
    name: getIdent(c.cache, g[si].fromDisk.strings[s.name])
  )
@@ -948,38 +872,24 @@ proc symBodyFromPacked(c: var PackedDecoder; g: var PackedModuleGraph;
    result.guard = loadSym(c, g, si, s.guard)
    result.bitsize = s.bitsize
    result.alignment = s.alignment
-  setOwner(result, loadSym(c, g, si, s.owner))
+  result.owner = loadSym(c, g, si, s.owner)
  let externalName = g[si].fromDisk.strings[s.externalName]
  if externalName != "":
-    result.locImpl.snippet = externalName
-  result.locImpl.flags = s.locFlags
+    result.loc.r = rope 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)
-    if si >= g.len:
-      g.pm.setLen(si+1)
-
-    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 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].syms[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:
@@ -988,7 +898,6 @@ 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]
@@ -996,23 +905,21 @@ proc loadSym(c: var PackedDecoder; g: var PackedModuleGraph; thisModule: int; s:
 proc typeHeaderFromPacked(c: var PackedDecoder; g: var PackedModuleGraph;
                          t: PackedType; si, item: int32): PType =
  result = PType(itemId: ItemId(module: si, item: t.nonUniqueId), kind: t.kind,
-                flagsImpl: t.flags, sizeImpl: t.size, alignImpl: t.align,
-                paddingAtEndImpl: t.paddingAtEnd,
+                flags: t.flags, size: t.size, align: t.align,
+                paddingAtEnd: t.paddingAtEnd,
                uniqueId: ItemId(module: si, item: item),
-                callConvImpl: t.callConv)
+                callConv: t.callConv)

 proc typeBodyFromPacked(c: var PackedDecoder; g: var PackedModuleGraph;
                        t: PackedType; si, item: int32; result: PType) =
  result.sym = loadSym(c, g, si, t.sym)
-  setOwner(result, loadSym(c, g, si, t.owner))
+  result.owner = 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:
-    sons.add loadType(c, g, si, son)
-  result.setSons(sons)
+    result.addSon loadType(c, g, si, son)
  loadAstBody(t, n)
  when false:
    for gen, id in items t.methods:
@@ -1026,20 +933,18 @@ 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.getOrDefault(t.item) == nil:
+    if g[si].types[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, "2"
+    assert result.itemId.item > 0

 proc setupLookupTables(g: var PackedModuleGraph; conf: ConfigRef; cache: IdentCache;
                       fileIdx: FileIndex; m: var LoadedModule) =
@@ -1064,12 +969,12 @@ proc setupLookupTables(g: var PackedModuleGraph; conf: ConfigRef; cache: IdentCa
  let filename = AbsoluteFile toFullPath(conf, fileIdx)
  # We cannot call ``newSym`` here, because we have to circumvent the ID
  # mechanism, which we do in order to assign each module a persistent ID.
-  m.module = PSym(kindImpl: skModule, itemId: ItemId(module: int32(fileIdx), item: 0'i32),
+  m.module = PSym(kind: skModule, itemId: ItemId(module: int32(fileIdx), item: 0'i32),
                  name: getIdent(cache, splitFile(filename).name),
-                  infoImpl: newLineInfo(fileIdx, 1, 1),
-                  positionImpl: int(fileIdx))
-  setOwner(m.module, getPackage(conf, cache, fileIdx))
-  m.module.flagsImpl = m.fromDisk.moduleFlags
+                  info: newLineInfo(fileIdx, 1, 1),
+                  position: int(fileIdx))
+  m.module.owner = getPackage(conf, cache, fileIdx)
+  m.module.flags = m.fromDisk.moduleFlags

 proc loadToReplayNodes(g: var PackedModuleGraph; conf: ConfigRef; cache: IdentCache;
                       fileIdx: FileIndex; m: var LoadedModule) =
@@ -1089,37 +994,30 @@ 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.pm.setLen(m+1)
+    g.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, ignoreConfig = conf.cmd == cmdM)
+    let err = loadRodFile(rod, g[m].fromDisk, conf)
    if err == ok:
-      if conf.cmd == cmdM:
+      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:
        setupLookupTables(g, conf, cache, fileIdx, g[m])
        cachedModules.add fileIdx
        g[m].status = loaded
-        result = false
      else:
-        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)
+        g[m] = LoadedModule(status: outdated, module: g[m].module)
    else:
      loadError(err, rod, conf)
      g[m].status = outdated
@@ -1134,13 +1032,12 @@ 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.
-  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)
+  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])

@@ -1154,43 +1051,46 @@ template setupDecoder() {.dirty.} =

 proc loadProcBody*(config: ConfigRef, cache: IdentCache;
                   g: var PackedModuleGraph; s: PSym): PNode =
-  bench g.loadBody:
-    let mId = s.itemId.module
+  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)
-    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 =
-  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)
+    result = loadType(decoder, g, module, id)

 proc loadSymFromId*(config: ConfigRef, cache: IdentCache;
                    g: var PackedModuleGraph; module: int; id: PackedItemId): PSym =
-  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)
+  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)

 proc translateId*(id: PackedItemId; g: PackedModuleGraph; thisModule: int; config: ConfigRef): ItemId =
  if id.module == LitId(0):
@@ -1198,6 +1098,19 @@ 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
@@ -1241,7 +1154,7 @@ proc initRodIter*(it: var RodIter; config: ConfigRef, cache: IdentCache;
    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),
@@ -1302,7 +1215,7 @@ proc rodViewer*(rodfile: AbsoluteFile; config: ConfigRef, cache: IdentCache) =
  if err != ok:
    config.quitOrRaise "Error: could not load: " & $rodfile.string & " reason: " & $err

-  when false:
+  when true:
    echo "exports:"
    for ex in m.exports:
      echo "  ", m.strings[ex[0]], " local ID: ", ex[1]
@@ -1318,32 +1231,13 @@ proc rodViewer*(rodfile: AbsoluteFile; config: ConfigRef, cache: IdentCache) =
    for ex in m.hidden:
      echo "  ", m.strings[ex[0]], " local ID: ", ex[1]

-  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 "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.len, " other nodes: ", m.bodies.len,
+    " top level nodes: ", m.topLevel.nodes.len, " other nodes: ", m.bodies.nodes.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
--- a/compiler/ic/integrity.nim
+++ b/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 std/[sets, tables]
+import sets

 when defined(nimPreviewSlimSystem):
  import std/assertions
@@ -72,16 +72,15 @@ proc checkForeignSym(c: var CheckedContext; symId: PackedItemId) =
    c.thisModule = oldThisModule

 proc checkNode(c: var CheckedContext; tree: PackedTree; n: NodePos) =
-  let t = findType(tree, n)
-  if t != nilItemId:
-    checkType(c, t)
+  if tree[n.int].typeId != nilItemId:
+    checkType(c, tree[n.int].typeId)
  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[n].soperand)
+    checkLocalSym(c, tree.nodes[n.int].operand)
  of directIntLit:
    discard
  of externIntLit, nkFloatLit..nkFloat128Lit:
@@ -90,9 +89,9 @@ 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 == nkNone
-    assert n2.kind == nkNone
-    checkForeignSym(c, PackedItemId(module: n1.litId, item: tree[n2].soperand))
+    assert n1.kind == nkInt32Lit
+    assert n2.kind == nkInt32Lit
+    checkForeignSym(c, PackedItemId(module: n1.litId, item: tree.nodes[n2.int].operand))
  else:
    for n0 in sonsReadonly(tree, n):
      checkNode(c, tree, n0)
@@ -108,18 +107,18 @@ 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 _, v in pairs(m.syms):
-    checkLocalSym c, v.id
+  for i in 0..high(m.syms):
+    checkLocalSym c, int32(i)

  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
@@ -135,15 +134,13 @@ proc checkModule(c: var CheckedContext; m: PackedModule) =
    typeInstCache*: seq[(PackedItemId, PackedItemId)]
    procInstCache*: seq[PackedInstantiation]
    attachedOps*: seq[(TTypeAttachedOp, PackedItemId, PackedItemId)]
-    methodsPerGenericType*: seq[(PackedItemId, int, PackedItemId)]
+    methodsPerType*: 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..<len(g.packed):
+  for i in 0..high(g.packed):
    # case statement here to enforce exhaustive checks.
    case g.packed[i].status
    of undefined:
@@ -153,3 +150,4 @@ proc checkIntegrity*(g: ModuleGraph) =
    of stored, storing, outdated, loaded:
      c.thisModule = int32 i
      checkModule(c, g.packed[i].fromDisk)
+
--- a/compiler/ic/navigator.nim
+++ b/compiler/ic/navigator.nim
@@ -7,38 +7,33 @@
 #    distribution, for details about the copyright.
 #

-## Supports the "nim check --ic:legacy --defusages:FILE,LINE,COL"
+## Supports the "nim check --ic:on --defusages:FILE,LINE,COL"
 ## IDE-like features. It uses the set of .rod files to accomplish
 ## its task. The set must cover a complete Nim project.

-import std/[sets, tables]
+import sets

-from std/os import nil
+from 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: UnpackedLineInfo
+    trackPos: PackedLineInfo
    alreadyEmitted: HashSet[string]
    outputSep: char # for easier testing, use short filenames and spaces instead of tabs.

-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:
+proc isTracked(current, trackPos: PackedLineInfo, tokenLen: int): bool =
+  if current.file == trackPos.file and current.line == trackPos.line:
    let col = trackPos.col
-    if col >= currentCol and col < currentCol+tokenLen:
+    if col >= current.col and col < current.col+tokenLen:
      result = true
    else:
      result = false
@@ -47,34 +42,32 @@ proc isTracked(man: LineInfoManager; current: PackedLineInfo, trackPos: Unpacked

 proc searchLocalSym(c: var NavContext; s: PackedSym; info: PackedLineInfo): bool =
  result = s.name != LitId(0) and
-    isTracked(c.g.packed[c.thisModule].fromDisk.man, info, c.trackPos, c.g.packed[c.thisModule].fromDisk.strings[s.name].len)
+    isTracked(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(c.g.packed[c.thisModule].fromDisk.man, info, c.trackPos, c.g.packed[s.module].fromDisk.strings[name].len)
+    isTracked(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..<len(tree):
-    let i = NodePos(i)
-    case tree[i].kind
+  for i in 0..high(tree.nodes):
+    case tree.nodes[i].kind
    of nkSym:
-      let item = tree[i].soperand
-      if searchLocalSym(c, c.g.packed[c.thisModule].fromDisk.syms[item], tree[i].info):
+      let item = tree.nodes[i].operand
+      if searchLocalSym(c, c.g.packed[c.thisModule].fromDisk.syms[item], tree.nodes[i].info):
        return ItemId(module: c.thisModule, item: item)
    of nkModuleRef:
-      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)
+      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)
        assert n1.kind == nkInt32Lit
        assert n2.kind == nkInt32Lit
-        let pId = PackedItemId(module: n1.litId, item: tree[n2].soperand)
+        let pId = PackedItemId(module: n1.litId, item: tree.nodes[n2.int].operand)
        let itemId = translateId(pId, c.g.packed, c.thisModule, c.g.config)
-        if searchForeignSym(c, itemId, tree[i].info):
+        if searchForeignSym(c, itemId, tree.nodes[i].info):
          return itemId
    else: discard
  return EmptyItemId
@@ -84,38 +77,36 @@ 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].kind in declarativeNodes
+  result = n.int >= 0 and tree[n.int].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[fileId]
+  var file = c.g.packed[c.thisModule].fromDisk.strings[info.file]
  if c.outputSep == ' ':
    file = os.extractFilename file
-  toLocation(m, file, line, col + ColOffset)
+  toLocation(m, file, info.line.int, info.col.int + 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..<len(tree):
-    let i = NodePos(i)
-    case tree[i].kind
+  for i in 0..high(tree.nodes):
+    case tree.nodes[i].kind
    of nkSym:
-      let item = tree[i].soperand
+      let item = tree.nodes[i].operand
      if sym.item == item and sym.module == c.thisModule:
-        usage(c, tree[i].info, isDecl(tree, parent(i)))
+        usage(c, tree.nodes[i].info, isDecl(tree, parent(NodePos i)))
    of nkModuleRef:
-      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 (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 itemId = translateId(pId, c.g.packed, c.thisModule, c.g.config)
      if itemId.item == sym.item and sym.module == itemId.module:
-        usage(c, tree[i].info, isDecl(tree, parent(i)))
+        usage(c, tree.nodes[i].info, isDecl(tree, parent(NodePos i)))
    else: discard

 proc searchForIncludeFile(g: ModuleGraph; fullPath: string): int =
-  for i in 0..<len(g.packed):
+  for i in 0..high(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.
@@ -147,7 +138,7 @@ proc nav(g: ModuleGraph) =
  var c = NavContext(
    g: g,
    thisModule: int32 mid,
-    trackPos: UnpackedLineInfo(line: unpacked.line.int, col: unpacked.col.int, file: fileId),
+    trackPos: PackedLineInfo(line: unpacked.line, col: unpacked.col, file: fileId),
    outputSep: if isDefined(g.config, "nimIcNavigatorTests"): ' ' else: '\t'
  )
  var symId = search(c, g.packed[mid].fromDisk.topLevel)
@@ -158,7 +149,7 @@ proc nav(g: ModuleGraph) =
    localError(g.config, unpacked, "no symbol at this position")
    return

-  for i in 0..<len(g.packed):
+  for i in 0..high(g.packed):
    # case statement here to enforce exhaustive checks.
    case g.packed[i].status
    of undefined:
@@ -175,7 +166,7 @@ proc navUsages*(g: ModuleGraph) = nav(g)
 proc navDefusages*(g: ModuleGraph) = nav(g)

 proc writeRodFiles*(g: ModuleGraph) =
-  for i in 0..<len(g.packed):
+  for i in 0..high(g.packed):
    case g.packed[i].status
    of undefined, loading, stored, loaded:
      discard "nothing to do"
--- a/compiler/ic/packed_ast.nim
+++ b/compiler/ic/packed_ast.nim
@@ -12,12 +12,10 @@
 ## use this representation directly in all the transformations,
 ## it is superior.

-import std/[hashes, tables, strtabs]
-import bitabs, rodfiles
+import hashes, tables, strtabs
+import bitabs
 import ".." / [ast, options]

-import iclineinfos
-
 when defined(nimPreviewSlimSystem):
  import std/assertions

@@ -33,12 +31,17 @@ type
    item*: int32         # same as the in-memory representation

 const
-  nilItemId* = PackedItemId(module: LitId(0), item: 0.int32)
+  nilItemId* = PackedItemId(module: LitId(0), item: -1.int32)

 const
  emptyNodeId* = NodeId(-1)

 type
+  PackedLineInfo* = object
+    line*: uint16
+    col*: int16
+    file*: LitId
+
  PackedLib* = object
    kind*: TLibKind
    generated*: bool
@@ -47,7 +50,6 @@ type
    path*: NodeId

  PackedSym* = object
-    id*: int32
    kind*: TSymKind
    name*: LitId
    typ*: PackedItemId
@@ -72,7 +74,6 @@ type
    instantiatedFrom*: PackedItemId

  PackedType* = object
-    id*: int32
    kind*: TTypeKind
    callConv*: TCallingConvention
    #nodekind*: TNodeKind
@@ -89,35 +90,23 @@ type
    typeInst*: PackedItemId
    nonUniqueId*: int32

-  PackedNode* = object     # 8 bytes
-    x: uint32
+  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
    info*: PackedLineInfo

  PackedTree* = object ## usually represents a full Nim module
-    nodes: seq[PackedNode]
-    withFlags: seq[(int32, TNodeFlags)]
-    withTypes: seq[(int32, PackedItemId)]
+    nodes*: seq[PackedNode]

  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.}

@@ -126,35 +115,71 @@ proc `==`*(a, b: NodePos): bool {.borrow.}
 proc `==`*(a, b: NodeId): bool {.borrow.}

 proc newTreeFrom*(old: PackedTree): PackedTree =
-  result = PackedTree(nodes: @[])
+  result.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(x: toX(nkIdent, uint32(s)), info: info)
+  tree.nodes.add PackedNode(kind: nkIdent, operand: int32(s), info: info)

 proc addSym*(tree: var PackedTree; s: int32; info: PackedLineInfo) =
-  tree.nodes.add PackedNode(x: toX(nkSym, cast[uint32](s)), info: info)
+  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)

 proc addSymDef*(tree: var PackedTree; s: SymId; info: PackedLineInfo) =
-  tree.nodes.add PackedNode(x: toX(nkSym, cast[uint32](s)), info: info)
+  tree.nodes.add PackedNode(kind: nkSym, operand: int32(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

-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)
+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 prepare*(tree: var PackedTree; kind: TNodeKind; flags: TNodeFlags; typeId: PackedItemId; info: PackedLineInfo): PatchPos =
  result = PatchPos tree.nodes.len
-  tree.addNode(kind = kind, flags = flags, operand = 0, info = info, typeId = typeId)
+  tree.nodes.add PackedNode(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
@@ -162,30 +187,26 @@ proc prepare*(dest: var PackedTree; source: PackedTree; sourcePos: NodePos): Pat

 proc patch*(tree: var PackedTree; pos: PatchPos) =
  let pos = pos.int
-  let k = tree.nodes[pos].kind
-  assert k > nkNilLit
+  assert tree.nodes[pos].kind > nkNilLit
  let distance = int32(tree.nodes.len - pos)
-  assert distance > 0
-  tree.nodes[pos].x = toX(k, cast[uint32](distance))
+  tree.nodes[pos].operand = distance

 proc len*(tree: PackedTree): int {.inline.} = tree.nodes.len

-proc `[]`*(tree: PackedTree; i: NodePos): lent PackedNode {.inline.} =
-  tree.nodes[i.int]
-
-template rawSpan(n: PackedNode): int = int(uoperand(n))
+proc `[]`*(tree: PackedTree; i: int): lent PackedNode {.inline.} =
+  tree.nodes[i]

 proc nextChild(tree: PackedTree; pos: var int) {.inline.} =
  if tree.nodes[pos].kind > nkNilLit:
-    assert tree.nodes[pos].uoperand > 0
-    inc pos, tree.nodes[pos].rawSpan
+    assert tree.nodes[pos].operand > 0
+    inc pos, tree.nodes[pos].operand
  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].rawSpan
+  let last = pos + tree.nodes[pos].operand
  inc pos
  while pos < last:
    yield NodePos pos
@@ -206,7 +227,7 @@ 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].rawSpan
+  let last = pos + tree.nodes[pos].operand
  inc pos
  if pos < last:
    nextChild tree, pos
@@ -220,7 +241,7 @@ 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].rawSpan
+  let last = pos + tree.nodes[pos].operand
  inc pos
  while pos < last and count > 2:
    yield NodePos pos
@@ -230,7 +251,7 @@ 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].rawSpan - 1 < n.int)):
+  while pos >= 0 and (isAtom(tree, pos) or (pos + tree.nodes[pos].operand - 1 < n.int)):
    dec pos
  #assert pos >= 0, "node has no parent"
  result = NodePos(pos)
@@ -256,32 +277,20 @@ 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].uoperand
+  LitId tree.nodes[n.int].operand
 proc info*(tree: PackedTree; n: NodePos): PackedLineInfo {.inline.} =
  tree.nodes[n.int].info

-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
-
-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)
+  tree.nodes[n.int].typeId
 template flags*(n: NodePos): TNodeFlags =
-  tree.findFlags(n)
+  tree.nodes[n.int].flags

-template uoperand*(n: NodePos): uint32 =
-  tree.nodes[n.int].uoperand
+template operand*(n: NodePos): int32 =
+  tree.nodes[n.int].operand

 proc span*(tree: PackedTree; pos: int): int {.inline.} =
-  if isAtom(tree, pos): 1 else: tree.nodes[pos].rawSpan
+  if isAtom(tree, pos): 1 else: tree.nodes[pos].operand

 proc sons2*(tree: PackedTree; n: NodePos): (NodePos, NodePos) =
  assert(not isAtom(tree, n.int))
@@ -311,28 +320,64 @@ 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].uoperand
+template litId*(n: NodePos): LitId = LitId tree.nodes[n.int].operand

-template symId*(n: NodePos): SymId = SymId tree.nodes[n.int].soperand
+template symId*(n: NodePos): SymId = SymId tree.nodes[n.int].operand

 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}
+    nkUInt64Lit} # nkInt32Lit is missing by design!

-  externSIntLit* = {nkIntLit, nkInt8Lit, nkInt16Lit, nkInt32Lit, nkInt64Lit}
+  externSIntLit* = {nkIntLit, nkInt8Lit, nkInt16Lit, nkInt64Lit}
  externUIntLit* = {nkUIntLit, nkUInt8Lit, nkUInt16Lit, nkUInt32Lit, nkUInt64Lit}
-  directIntLit* = nkNone
+  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)

 template copyInto*(dest, n, body) =
  let patchPos = prepare(dest, tree, n)
@@ -344,8 +389,28 @@ 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:
@@ -355,13 +420,3 @@ 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
--- a/compiler/ic/replayer.nim
+++ b/compiler/ic/replayer.nim
@@ -14,7 +14,7 @@
 import ".." / [ast, modulegraphs, trees, extccomp, btrees,
  msgs, lineinfos, pathutils, options, cgmeth]

-import std/tables
+import tables

 when defined(nimPreviewSlimSystem):
  import std/assertions
@@ -103,17 +103,6 @@ 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
@@ -138,12 +127,12 @@ 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.methodsPerGenericType):
+  for it in mitems(g.packed[module].fromDisk.methodsPerType):
    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.methodsPerGenericType.mgetOrPut(key, @[]).add (col, LazySym(id: symId, sym: nil))
+    g.methodsPerType.mgetOrPut(key, @[]).add (col, LazySym(id: symId, sym: nil))

  replayBackendProcs(g, module)

--- a/compiler/ic/rodfiles.nim
+++ b/compiler/ic/rodfiles.nim
@@ -14,13 +14,11 @@
 ##     compiler works and less a storage format, you're probably looking for
 ##     the `ic` or `packed_ast` modules to understand the logical format.

-from std/typetraits import supportsCopyMem
+from typetraits import supportsCopyMem

 when defined(nimPreviewSlimSystem):
  import std/[syncio, assertions]

-import std / tables
-
 ## Overview
 ## ========
 ## `RodFile` represents a Rod File (versioned binary format), and the
@@ -94,16 +92,11 @@ type
    typeInstCacheSection
    procInstCacheSection
    attachedOpsSection
-    methodsPerGenericTypeSection
-    enumToStringProcsSection
    methodsPerTypeSection
-    dispatchersSection
+    enumToStringProcsSection
    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,
@@ -116,8 +109,8 @@ type
                       # better than exceptions.

 const
-  RodVersion = 2
-  defaultCookie = [byte(0), byte('R'), byte('O'), byte('D'),
+  RodVersion = 1
+  cookie = [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.} =
@@ -172,18 +165,6 @@ 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
@@ -225,26 +206,13 @@ proc loadSeq*[T](f: var RodFile; s: var seq[T]) =
    for i in 0..<lenPrefix:
      loadPrim(f, s[i])

-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) =
+proc storeHeader*(f: var RodFile) =
  ## 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; cookie = defaultCookie) =
+proc loadHeader*(f: var RodFile) =
  ## Loads the header which is described by `cookie`.
  if f.err != ok: return
  var thisCookie: array[cookie.len, byte] = default(array[cookie.len, byte])
--- a/compiler/idents.nim
+++ b/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 wordrecg
-import std/hashes
+import
+  hashes, wordrecg

 when defined(nimPreviewSlimSystem):
  import std/assertions
--- a/compiler/importer.nim
+++ b/compiler/importer.nim
@@ -10,12 +10,10 @@
 ## This module implements the symbol importing mechanism.

 import
-  ast, 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]
+  intsets, ast, astalgo, msgs, options, idents, lookups,
+  semdata, modulepaths, sigmatch, lineinfos, sets,
+  modulegraphs, wordrecg, tables
+from strutils import `%`

 when defined(nimPreviewSlimSystem):
  import std/assertions
@@ -144,7 +142,7 @@ 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 = default(ModuleIter)
+      var it: 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")
@@ -231,7 +229,12 @@ 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 importModuleAs(c: PContext; n: PNode, realModule: PSym, importHidden, trackUnusedImport: bool): PSym =
+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 =
    createModuleAlias(realModule, c.idgen, ident, n.info, c.config.options)
@@ -245,18 +248,13 @@ proc importModuleAs(c: PContext; n: PNode, realModule: PSym, importHidden, track
    # avoids modifying `realModule`, see D20201209T194412 for `import {.all.}`
    result = createModuleAliasImpl(realModule.name)
  if importHidden:
-    ensureMutable result
-    result.optionsImpl.incl optImportHidden
-  let moduleIdent = if n.kind in {nkInfix, nkImportAs}: n[^1] else: n
-  result.info = moduleIdent.info
-  if trackUnusedImport:
-    c.unusedImports.add((result, result.info))
+    result.options.incl optImportHidden
+  c.unusedImports.add((result, n.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] =
-  result = (nil, false)
-  var ret = default(typeof(result))
+  var ret: typeof(result)
  proc processPragma(n2: PNode): PNode =
    let (result2, kws) = splitPragmas(c, n2)
    result = result2
@@ -291,11 +289,10 @@ proc myImportModule(c: PContext, n: var PNode, importStmtResult: PNode): PSym =
                toFullPath(c.config, c.graph.importStack[i+1])
      c.recursiveDep = err

-    let trackUnusedImport = warnUnusedImportX in c.config.notes
    var realModule: PSym
    discard pushOptionEntry(c)
    realModule = c.graph.importModuleCallback(c.graph, c.module, f)
-    result = importModuleAs(c, n, realModule, transf.importHidden, trackUnusedImport)
+    result = importModuleAs(c, n, realModule, transf.importHidden)
    popOptionEntry(c)

    #echo "set back to ", L
@@ -308,26 +305,13 @@ 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:
-        suggestMod(n[0], realModule)
-      elif n.kind == nkInfix:
-        suggestMod(n[2], s)
-      else:
-        suggestSym(c.graph, n.info, s, c.graph.usageSym, false)
-    suggestMod(n, result)
+    suggestSym(c.graph, n.info, result, c.graph.usageSym, false)
    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):
@@ -339,7 +323,7 @@ proc impMod(c: PContext; it: PNode; importStmtResult: PNode) =
  let m = myImportModule(c, it, importStmtResult)
  if m != nil:
    # ``addDecl`` needs to be done before ``importAllSymbols``!
-    addDecl(c, m) # add symbol to symbol table of module
+    addDecl(c, m, it.info) # add symbol to symbol table of module
    importAllSymbols(c, m)
    #importForwarded(c, m.ast, emptySet, m)
    afterImport(c, m)
@@ -376,7 +360,7 @@ proc evalFrom*(c: PContext, n: PNode): PNode =
  var m = myImportModule(c, n[0], result)
  if m != nil:
    n[0] = newSymNode(m)
-    addDecl(c, m)               # add symbol to symbol table of module
+    addDecl(c, m, n.info)               # add symbol to symbol table of module

    var im = ImportedModule(m: m, mode: importSet, imported: initIntSet())
    for i in 1..<n.len:
@@ -391,7 +375,7 @@ proc evalImportExcept*(c: PContext, n: PNode): PNode =
  var m = myImportModule(c, n[0], result)
  if m != nil:
    n[0] = newSymNode(m)
-    addDecl(c, m)               # add symbol to symbol table of module
+    addDecl(c, m, n.info)               # add symbol to symbol table of module
    importAllSymbolsExcept(c, m, readExceptSet(c, n))
    #importForwarded(c, m.ast, exceptSet, m)
    afterImport(c, m)
--- a/compiler/injectdestructors.nim
+++ b/compiler/injectdestructors.nim
@@ -14,17 +14,15 @@
 ## See doc/destructors.rst for a spec of the implemented rewrite rules

 import
-  ast, astalgo, msgs, renderer, magicsys, types, idents,
-  options, lowerings, modulegraphs,
+  intsets, strtabs, ast, astalgo, msgs, renderer, magicsys, types, idents,
+  strutils, options, lowerings, tables, modulegraphs,
  lineinfos, parampatterns, sighashes, liftdestructors, optimizer,
  varpartitions, aliasanalysis, dfa, wordrecg

-import std/[strtabs, tables, strutils, intsets]
-
 when defined(nimPreviewSlimSystem):
  import std/assertions

-from trees import exprStructuralEquivalent, getRoot, whichPragma, getPotentialWrites
+from trees import exprStructuralEquivalent, getRoot, whichPragma

 type
  Con = object
@@ -100,7 +98,6 @@ when false:
 proc isLastReadImpl(n: PNode; c: var Con; scope: var Scope): bool =
  let root = parampatterns.exprRoot(n, allowCalls=false)
  if root == nil: return false
-  elif sfSingleUsedTemp in root.flags: return true

  var s = addr(scope)
  while s != nil:
@@ -163,16 +160,12 @@ proc isLastReadImpl(n: PNode; c: var Con; scope: var Scope): bool =
  else:
    result = false

-template hasDestructorOrAsgn(c: var Con, typ: PType): bool =
-  # bug #23354; an object type could have a non-trivial assignements when it is passed to a sink parameter
-  hasDestructor(c, typ) or (c.graph.config.selectedGC == gcRefc and typ.kind == tyString) or (c.graph.config.selectedGC in {gcArc, gcOrc, gcAtomicArc} and
-        typ.kind == tyObject and not isTrivial(getAttachedOp(c.graph, typ, attachedAsgn)))
-
 proc isLastRead(n: PNode; c: var Con; s: var Scope): bool =
-  if not hasDestructorOrAsgn(c, n.typ.skipTypes({tyGenericInst, tyAlias, tySink})): return true
+  if not hasDestructor(c, n.typ): return true

  let m = skipConvDfa(n)
-  result = isLastReadImpl(n, c, s)
+  result = (m.kind == nkSym and sfSingleUsedTemp in m.sym.flags) or
+      isLastReadImpl(n, c, s)

 proc isFirstWrite(n: PNode; c: var Con): bool =
  let m = skipConvDfa(n)
@@ -189,11 +182,10 @@ proc isCursor(n: PNode): bool =
  else:
    false

-template isFullyUnpackedTuple(n: PNode): bool =
+template isUnpackedTuple(n: PNode): bool =
  ## we move out all elements of unpacked tuples,
  ## hence unpacked tuples themselves don't need to be destroyed
  ## except it's already a cursor
-  ## restricted to `skTemp`, tuple temps where not every field is unpacked should not use `skTemp`
  (n.kind == nkSym and n.sym.kind == skTemp and
   n.sym.typ.kind == tyTuple and sfCursor notin n.sym.flags)

@@ -202,8 +194,7 @@ proc checkForErrorPragma(c: Con; t: PType; ri: PNode; opname: string; inferredFr
  if inferredFromCopy:
    m.add ", which is inferred from unavailable '=copy'"

-  if (opname == "=" or opname == "=copy" or opname == "=dup") and
-       ri != nil:
+  if (opname == "=" or opname == "=copy" or opname == "=dup") and ri != nil:
    m.add "; requires a copy because it's not the last read of '"
    m.add renderTree(ri)
    m.add '\''
@@ -218,17 +209,15 @@ 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, c.idgen, c.owner)
+  result = newType(tyPtr, nextTypeId 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.signatureLen > 1 and op.typ.firstParamType.kind != tyVar:
+  if op.typ != nil and op.typ.len > 1 and op.typ[1].kind != tyVar:
    addrExp = dest
  else:
    addrExp = newNodeIT(nkHiddenAddr, dest.info, makePtrType(c, dest.typ))
@@ -253,12 +242,7 @@ proc genOp(c: var Con; t: PType; kind: TTypeAttachedOp; dest, ri: PNode): PNode
  dbg:
    if kind == attachedDestructor:
      echo "destructor is ", op.id, " ", op.ast
-  if sfError in op.flags:
-    if ri != nil:
-      checkForErrorPragma(c, t, ri, AttachedOpToStr[kind])
-    else:
-      # uses the lineinfos of `dest` is `ri` is not available
-      checkForErrorPragma(c, t, dest, AttachedOpToStr[kind])
+  if sfError in op.flags: checkForErrorPragma(c, t, ri, AttachedOpToStr[kind])
  c.genOp(op, dest)

 proc genDestroy(c: var Con; dest: PNode): PNode =
@@ -286,9 +270,7 @@ proc deepAliases(dest, ri: PNode): bool =
    return aliases(dest, ri) != no

 proc genSink(c: var Con; s: var Scope; dest, ri: PNode; flags: set[MoveOrCopyFlag] = {}): PNode =
-  if c.graph.config.selectedGC == gcRefc and dest.typ.skipTypes({tyGenericInst, tyAlias, tySink}).kind == tyString:
-    result = newFastAsgnStmt(dest, callCodegenProc(c.graph, "moveString", dest.info, ri))
-  elif (c.inLoopCond == 0 and (isFullyUnpackedTuple(dest) or IsDecl in flags or
+  if (c.inLoopCond == 0 and (isUnpackedTuple(dest) or IsDecl in flags or
      (isAnalysableFieldAccess(dest, c.owner) and isFirstWrite(dest, c)))) or
      isNoInit(dest) or IsReturn in flags:
    # optimize sink call into a bitwise memcopy
@@ -313,7 +295,7 @@ proc genSink(c: var Con; s: var Scope; dest, ri: PNode; flags: set[MoveOrCopyFla
 proc isCriticalLink(dest: PNode): bool {.inline.} =
  #[
  Lins's idea that only "critical" links can introduce a cycle. This is
-  critical for the performance guarantees that we strive for: If you
+  critical for the performance gurantees that we strive for: If you
  traverse a data structure, no tracing will be performed at all.
  ORC is about this promise: The GC only touches the memory that the
  mutator touches too.
@@ -330,10 +312,9 @@ proc isCriticalLink(dest: PNode): bool {.inline.} =
  ]#
  result = dest.kind != nkSym

-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})
+proc finishCopy(c: var Con; result, dest: PNode; isFromSink: bool) =
+  if c.graph.config.selectedGC == gcOrc:
+    let t = dest.typ.skipTypes({tyGenericInst, tyAlias, tySink, tyDistinct})
    if cyclicType(c.graph, t):
      result.add boolLit(c.graph, result.info, isFromSink or isCriticalLink(dest))

@@ -354,9 +335,6 @@ proc genCopyNoCheck(c: var Con; dest, ri: PNode; a: TTypeAttachedOp): PNode =
  assert ri.typ != nil

 proc genCopy(c: var Con; dest, ri: PNode; flags: set[MoveOrCopyFlag]): PNode =
-  if c.graph.config.selectedGC == gcRefc and dest.typ.skipTypes({tyGenericInst, tyAlias, tySink}).kind == tyString:
-    result = newAsgnStmt(dest, ri)
-    return
  if c.inEnsureMove > 0:
    localError(c.graph.config, ri.info, errFailedMove, "cannot move '" & $ri &
                                                      "', which introduces an implicit copy")
@@ -416,7 +394,7 @@ proc genWasMoved(c: var Con, n: PNode): PNode =
    result = genOp(c, op, n)
  else:
    result = newNodeI(nkCall, n.info)
-    result.add(newSymNode(createMagic(c.graph, c.idgen, "wasMoved", mWasMoved)))
+    result.add(newSymNode(createMagic(c.graph, c.idgen, "`=wasMoved`", mWasMoved)))
    result.add copyTree(n) #mWasMoved does not take the address
    #if n.kind != nkSym:
    #  message(c.graph.config, n.info, warnUser, "wasMoved(" & $n & ")")
@@ -429,10 +407,7 @@ proc genDefaultCall(t: PType; c: Con; info: TLineInfo): PNode =
 proc destructiveMoveVar(n: PNode; c: var Con; s: var Scope): PNode =
  # generate: (let tmp = v; reset(v); tmp)
  if (not hasDestructor(c, n.typ)) and c.inEnsureMove == 0:
-    assert n.kind != nkSym or not hasDestructor(c, n.sym.typ) or
-          (n.typ.kind == tyPtr and n.sym.typ.kind == tyRef)
-      # bug #23505; transformed by `transf`: addr (deref ref) -> ptr
-      # we know it's really a pointer; so here we assign it directly
+    assert n.kind != nkSym or not hasDestructor(c, n.sym.typ)
    result = copyTree(n)
  else:
    result = newNodeIT(nkStmtListExpr, n.info, n.typ)
@@ -463,25 +438,24 @@ proc isCapturedVar(n: PNode): bool =

 proc passCopyToSink(n: PNode; c: var Con; s: var Scope): PNode =
  result = newNodeIT(nkStmtListExpr, n.info, n.typ)
-  let nTyp = n.typ.skipTypes(tyUserTypeClasses)
-  let tmp = c.getTemp(s, nTyp, n.info)
-  if hasDestructorOrAsgn(c, nTyp):
-    let typ = nTyp.skipTypes({tyGenericInst, tyAlias, tySink})
+  let tmp = c.getTemp(s, n.typ, n.info)
+  if hasDestructor(c, n.typ):
+    let typ = n.typ.skipTypes({tyGenericInst, tyAlias, tySink})
    let op = getAttachedOp(c.graph, typ, attachedDup)
    if op != nil and tfHasOwned notin typ.flags:
      if sfError in op.flags:
-        c.checkForErrorPragma(nTyp, n, "=dup")
+        c.checkForErrorPragma(n.typ, n, "=dup")
      else:
        let copyOp = getAttachedOp(c.graph, typ, attachedAsgn)
        if copyOp != nil and sfError in copyOp.flags and
           sfOverridden notin op.flags:
-          c.checkForErrorPragma(nTyp, n, "=dup", inferredFromCopy = true)
+          c.checkForErrorPragma(n.typ, n, "=dup", inferredFromCopy = true)

      let src = p(n, c, s, normal)
      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
@@ -490,9 +464,9 @@ 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:
+    if isLValue(n) and not isCapturedVar(n) and n.typ.skipTypes(abstractInst).kind != tyRef and c.inSpawn == 0:
      message(c.graph.config, n.info, hintPerformance,
        ("passing '$1' to a sink parameter introduces an implicit copy; " &
        "if possible, rearrange your program's control flow to prevent it") % $n)
@@ -501,8 +475,8 @@ proc passCopyToSink(n: PNode; c: var Con; s: var Scope): PNode =
        ("cannot move '$1', passing '$1' to a sink parameter introduces an implicit copy") % $n)
  else:
    if c.graph.config.selectedGC in {gcArc, gcOrc, gcAtomicArc}:
-      assert(not containsManagedMemory(nTyp))
-    if nTyp.skipTypes(abstractInst).kind in {tyOpenArray, tyVarargs}:
+      assert(not containsManagedMemory(n.typ))
+    if n.typ.skipTypes(abstractInst).kind in {tyOpenArray, tyVarargs}:
      localError(c.graph.config, n.info, "cannot create an implicit openArray copy to be passed to a sink parameter")
    result.add newTree(nkAsgn, tmp, p(n, c, s, normal))
  # Since we know somebody will take over the produced copy, there is
@@ -511,14 +485,14 @@ 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.elementType.flags
+  result = t.kind == tySequence and tfHasOwned notin t[0].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, nkCast:
+  of nkExprEqExpr, nkExprColonExpr, nkHiddenStdConv, nkHiddenSubConv:
    result = containsConstSeq(n[1])
  of nkObjConstr, nkClosure:
    for i in 1..<n.len:
@@ -575,7 +549,7 @@ proc cycleCheck(n: PNode; c: var Con) =
 proc pVarTopLevel(v: PNode; c: var Con; s: var Scope; res: PNode) =
  # move the variable declaration to the top of the frame:
  s.vars.add v.sym
-  if isFullyUnpackedTuple(v):
+  if isUnpackedTuple(v):
    if c.inLoop > 0:
      # unpacked tuple needs reset at every loop iteration
      res.add newTree(nkFastAsgn, v, genDefaultCall(v.typ, c, v.info))
@@ -616,9 +590,7 @@ template processScopeExpr(c: var Con; s: var Scope; ret: PNode, processCall: unt
  # tricky because you would have to intercept moveOrCopy at a certain point
  let tmp = c.getTemp(s.parent[], ret.typ, ret.info)
  tmp.sym.flags = tmpFlags
-  let cpy = if hasDestructor(c, ret.typ) and
-                ret.typ.kind notin {tyOpenArray, tyVarargs}:
-                # bug #23247 we don't own the data, so it's harmful to destroy it
+  let cpy = if hasDestructor(c, ret.typ):
              s.parent[].final.add c.genDestroy(tmp)
              moveOrCopy(tmp, ret, c, s, {IsDecl})
            else:
@@ -670,7 +642,7 @@ 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 n.typ.isEmptyType or it[^1].typ.isEmptyType or willProduceStmt:
+      branch[^1] = if it[^1].typ.isEmptyType or willProduceStmt:
                     processScope(c, ofScope, maybeVoid(it[^1], ofScope))
                   else:
                     processScopeExpr(c, ofScope, it[^1], processCall, tmpFlags)
@@ -718,7 +690,7 @@ 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 n.typ.isEmptyType or it[^1].typ.isEmptyType or willProduceStmt:
+      branch[^1] = if it[^1].typ.isEmptyType or willProduceStmt:
                     processScope(c, branchScope, maybeVoid(it[^1], branchScope))
                   else:
                     processScopeExpr(c, branchScope, it[^1], processCall, tmpFlags)
@@ -778,7 +750,7 @@ 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
@@ -793,18 +765,6 @@ proc pRaiseStmt(n: PNode, c: var Con; s: var Scope): PNode =
      result.add copyNode(n[0])
  s.needsTry = true

-template isCustomDestructor(c: Con, t: PType): bool =
-  hasDestructor(c, t) and
-          getAttachedOp(c.graph, t, attachedDestructor) != nil and
-          sfOverridden in getAttachedOp(c.graph, t, attachedDestructor).flags
-
-proc hasCustomDestructor(c: Con, t: PType): bool =
-  result = isCustomDestructor(c, t)
-  var obj = t
-  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 =
  if n.kind in {nkStmtList, nkStmtListExpr, nkBlockStmt, nkBlockExpr, nkIfStmt,
                nkIfExpr, nkCaseStmt, nkWhen, nkWhileStmt, nkParForStmt, nkTryStmt, nkPragmaBlock}:
@@ -818,7 +778,15 @@ proc p(n: PNode; c: var Con; s: var Scope; mode: ProcessMode; tmpFlags = {sfSing
      result = passCopyToSink(n, c, s)
    elif n.kind in {nkBracket, nkObjConstr, nkTupleConstr, nkClosure, nkNilLit} +
         nkCallKinds + nkLiterals:
-      result = p(n, c, s, consumed)
+      if n.kind in nkCallKinds and n[0].kind == nkSym:
+        if n[0].sym.magic == mEnsureMove:
+          inc c.inEnsureMove
+          result = p(n[1], c, s, sinkArg)
+          dec c.inEnsureMove
+        else:
+          result = p(n, c, s, consumed)
+      else:
+        result = p(n, c, s, consumed)
    elif ((n.kind == nkSym and isSinkParam(n.sym)) or isAnalysableFieldAccess(n, c.owner)) and
        isLastRead(n, c, s) and not (n.kind == nkSym and isCursor(n)):
      # Sinked params can be consumed only once. We need to reset the memory
@@ -838,9 +806,6 @@ proc p(n: PNode; c: var Con; s: var Scope; mode: ProcessMode; tmpFlags = {sfSing
    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)
@@ -884,25 +849,29 @@ 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 or field.typ.kind in {tyOpenArray, tyVarargs}):
-            # don't sink fields with openarray types
+          if field != nil and sfCursor in field.flags:
            result[i][1] = p(n[i][1], c, s, normal)
          else:
            result[i][1] = p(n[i][1], c, s, m)
        else:
          result[i] = p(n[i], c, s, m)
-      if mode == normal and (isRefConstr or hasCustomDestructor(c, t)):
+      if mode == normal and isRefConstr:
        result = ensureDestruction(result, n, c, s)
    of nkCallKinds:
+      if n[0].kind == nkSym and n[0].sym.magic == mEnsureMove:
+        inc c.inEnsureMove
+        result = p(n[1], c, s, sinkArg)
+        dec c.inEnsureMove
+        return
+
      let inSpawn = c.inSpawn
      if n[0].kind == nkSym and n[0].sym.magic == mSpawn:
        c.inSpawn.inc
      elif c.inSpawn > 0:
        c.inSpawn.dec

-      # 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
+      let parameters = n[0].typ
+      let L = if parameters != nil: parameters.len else: 0

      when false:
        var isDangerous = false
@@ -911,19 +880,13 @@ proc p(n: PNode; c: var Con; s: var Scope; mode: ProcessMode; tmpFlags = {sfSing
          isDangerous = true

      result = shallowCopy(n)
-
-      if n[0].kind == nkSym and n[0].sym.magic == mEnsureMove:
-        inc c.inEnsureMove
-        result[1] = p(n[1], c, s, sinkArg)
-        dec c.inEnsureMove
-      else:
-        for i in 1..<n.len:
-          if i < L and isCompileTimeOnly(parameters[i]):
-            result[i] = n[i]
-          elif i < L and (isSinkTypeForParam(parameters[i]) or inSpawn > 0):
-            result[i] = p(n[i], c, s, sinkArg)
-          else:
-            result[i] = p(n[i], c, s, normal)
+      for i in 1..<n.len:
+        if i < L and isCompileTimeOnly(parameters[i]):
+          result[i] = n[i]
+        elif i < L and (isSinkTypeForParam(parameters[i]) or inSpawn > 0):
+          result[i] = p(n[i], c, s, sinkArg)
+        else:
+          result[i] = p(n[i], c, s, normal)

      when false:
        if isDangerous:
@@ -938,10 +901,7 @@ proc p(n: PNode; c: var Con; s: var Scope; mode: ProcessMode; tmpFlags = {sfSing
        result[0] = p(n[0], c, s, normal)
      if canRaise(n[0]): s.needsTry = true
      if mode == normal:
-        if result.typ != nil and result.typ.kind notin {tyOpenArray, tyVarargs}:
-          # Returns of openarray types shouldn't be destroyed
-          # bug #19435; # bug #23247
-          result = ensureDestruction(result, n, c, s)
+        result = ensureDestruction(result, n, c, s)
    of nkDiscardStmt: # Small optimization
      result = shallowCopy(n)
      if n[0].kind != nkEmpty:
@@ -951,9 +911,6 @@ proc p(n: PNode; c: var Con; s: var Scope; mode: ProcessMode; tmpFlags = {sfSing
    of nkVarSection, nkLetSection:
      # transform; var x = y to  var x; x op y  where op is a move or copy
      result = newNodeI(nkStmtList, n.info)
-
-      let isInProc = c.owner.kind in {skProc, skFunc, skMethod, skIterator, skConverter}
-
      for it in n:
        var ri = it[^1]
        if it.kind == nkVarTuple and hasDestructor(c, ri.typ):
@@ -969,15 +926,7 @@ proc p(n: PNode; c: var Con; s: var Scope; mode: ProcessMode; tmpFlags = {sfSing
              s.locals.add v.sym
              pVarTopLevel(v, c, s, result)
            if ri.kind != nkEmpty:
-              let isGlobalPragma = v.kind == nkSym and
-                      {sfPure, sfGlobal} <= v.sym.flags and
-                      isInProc
-
-              if isGlobalPragma:
-                c.graph.procGlobals.add newTree(nkFastAsgn, v, ri)
-              else:
-                let value = moveOrCopy(v, ri, c, s, if v.kind == nkSym: {IsDecl} else: {})
-                result.add value
+              result.add moveOrCopy(v, ri, c, s, if v.kind == nkSym: {IsDecl} else: {})
            elif ri.kind == nkEmpty and c.inLoop > 0:
              let skipInit = v.kind == nkDotExpr and # Closure var
                             sfNoInit in v[1].sym.flags
@@ -1149,25 +1098,6 @@ proc genFieldAccessSideEffects(c: var Con; s: var Scope; dest, ri: PNode; flags:
  var snk = c.genSink(s, dest, newAccess, flags)
  result = newTree(nkStmtList, v, snk, c.genWasMoved(newAccess))

-proc ownsData(c: var Con; s: var Scope; orig: PNode; flags: set[MoveOrCopyFlag]): PNode =
-  var n = orig
-  while true:
-    case n.kind
-    of nkDotExpr, nkCheckedFieldExpr, nkBracketExpr:
-      n = n[0]
-    else:
-      break
-  if n.kind in nkCallKinds and n.typ != nil and hasDestructor(c, n.typ):
-    result = newNodeIT(nkStmtListExpr, orig.info, orig.typ)
-    let tmp = c.getTemp(s, n.typ, n.info)
-    tmp.sym.flagsImpl.incl sfSingleUsedTemp
-    result.add newTree(nkFastAsgn, tmp, copyTree(n))
-    s.final.add c.genDestroy(tmp)
-    n[] = tmp[]
-    result.add copyTree(orig)
-  else:
-    result = nil
-
 proc moveOrCopy(dest, ri: PNode; c: var Con; s: var Scope, flags: set[MoveOrCopyFlag] = {}): PNode =
  var ri = ri
  var isEnsureMove = 0
@@ -1194,7 +1124,7 @@ proc moveOrCopy(dest, ri: PNode; c: var Con; s: var Scope, flags: set[MoveOrCopy
    of nkCallKinds:
      result = c.genSink(s, dest, p(ri, c, s, consumed), flags)
    of nkBracketExpr:
-      if isFullyUnpackedTuple(ri[0]):
+      if isUnpackedTuple(ri[0]):
        # unpacking of tuple: take over the elements
        result = c.genSink(s, dest, p(ri, c, s, consumed), flags)
      elif isAnalysableFieldAccess(ri, c.owner) and isLastRead(ri, c, s):
@@ -1212,7 +1142,7 @@ 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, flags, isFromSink = false)
+        c.finishCopy(result, dest, isFromSink = false)
    of nkBracket:
      # array constructor
      if ri.len > 0 and isDangerousSeq(ri.typ):
@@ -1220,7 +1150,7 @@ 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, flags, isFromSink = false)
+        c.finishCopy(result, dest, isFromSink = false)
      else:
        result = c.genSink(s, dest, p(ri, c, s, consumed), flags)
    of nkObjConstr, nkTupleConstr, nkClosure, nkCharLit..nkNilLit:
@@ -1230,9 +1160,9 @@ 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
-          isAnalysableFieldAccess(ri, c.owner) and
-          isLastRead(ri, c, s) and canBeMoved(c, dest.typ):
+      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) and
+          not ({sfGlobal, sfPure} <= ri.sym.flags):
        # Rule 3: `=sink`(x, z); wasMoved(z)
        let snk = c.genSink(s, dest, ri, flags)
        result = newTree(nkStmtList, snk, c.genWasMoved(ri))
@@ -1241,24 +1171,17 @@ 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, flags, isFromSink = false)
+        c.finishCopy(result, dest, isFromSink = false)
    of nkHiddenSubConv, nkHiddenStdConv, nkConv, nkObjDownConv, nkObjUpConv, nkCast:
-      if IsExplicitSink in flags:
-        result = c.genSink(s, dest, p(ri, c, s, consumed), flags)
-      else:
-        result = c.genSink(s, dest, p(ri, c, s, sinkArg), flags)
-    of nkStmtListExpr, nkBlockExpr, nkIfExpr, nkCaseStmt, nkTryStmt, nkPragmaBlock:
+      result = c.genSink(s, dest, p(ri, c, s, sinkArg), flags)
+    of nkStmtListExpr, nkBlockExpr, nkIfExpr, nkCaseStmt, nkTryStmt:
      template process(child, s): untyped = moveOrCopy(dest, child, c, s, flags)
      # We know the result will be a stmt so we use that fact to optimize
      handleNestedTempl(ri, process, willProduceStmt = true)
    of nkRaiseStmt:
      result = pRaiseStmt(ri, c, s)
    else:
-      let isOwnsData = ownsData(c, s, ri2, flags)
-
-      if isOwnsData != nil:
-        result = moveOrCopy(dest, isOwnsData, c, s, flags)
-      elif isAnalysableFieldAccess(ri, c.owner) and isLastRead(ri, c, s) and
+      if 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)
@@ -1268,7 +1191,7 @@ 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, flags, isFromSink = false)
+        c.finishCopy(result, dest, isFromSink = false)

 when false:
  proc computeUninit(c: var Con) =
@@ -1297,55 +1220,6 @@ when false:
      for i in 0..<n.safeLen:
        injectDefaultCalls(n[i], c)

-proc replaceSinkParam(n: PNode, mapping: Table[int, PSym]): PNode =
-  case n.kind
-  of nkSym:
-    if n.sym.id in mapping:
-      result = newSymNode(mapping[n.sym.id])
-    else:
-      result = n
-  of nkVarSection, nkLetSection:
-    result = copyNode(n)
-    newSons(result, n.len)
-    for i in 0..<n.len:
-      result[i] = copyNode(n[i])
-      for j in 0..<n[i].len-1:
-        result[i].add n[i][j]
-      result[i].add replaceSinkParam(n[i][^1], mapping)
-  of {nkNone..nkNilLit}-{nkSym}, nkTypeSection, nkProcDef, nkConverterDef,
-      nkMethodDef, nkIteratorDef, nkMacroDef, nkTemplateDef, nkLambda, nkDo,
-      nkFuncDef, nkConstSection, nkConstDef, nkIncludeStmt, nkImportStmt,
-      nkExportStmt, nkPragma, nkCommentStmt, nkBreakState,
-      nkTypeOfExpr, nkMixinStmt, nkBindStmt:
-    result = n
-  else:
-    result = copyNode(n)
-    for i in 0..<n.len:
-      result.add replaceSinkParam(n[i], mapping)
-
-proc addSinkCopy(c: var Con; s: var Scope; sinkParams: seq[PSym]; n: PNode): PNode =
-  result = newNodeI(nkStmtList, n.info)
-  var mapping = initTable[int, PSym]()
-
-  var mutated = newSeq[PNode]()
-  getPotentialWrites(n, false, mutated)
-  var mutatedSet = initIntSet()
-  for m in mutated:
-    mutatedSet.incl m.sym.id
-  for param in sinkParams:
-    if param.id in mutatedSet:
-      let newSym = newSym(skTemp, getIdent(c.graph.cache, "sinkCopy"), c.idgen, param.owner, n.info)
-      newSym.flagsImpl.incl sfFromGeneric
-      newSym.typ = param.typ.elementType
-      mapping[param.id] = newSym
-      let v = newNodeI(nkVarSection, n.info)
-      v.addVar(newSymNode(newSym), newSymNode(param))
-      result.add v
-  if mapping.len > 0:
-    result.add replaceSinkParam(n, mapping)
-  else:
-    result = n
-
 proc injectDestructorCalls*(g: ModuleGraph; idgen: IdGenerator; owner: PSym; n: PNode): PNode =
  when toDebug.len > 0:
    shouldDebug = toDebug == owner.name.s or toDebug == "always"
@@ -1359,24 +1233,15 @@ proc injectDestructorCalls*(g: ModuleGraph; idgen: IdGenerator; owner: PSym; n:
  var scope = Scope(body: n)
  let body = p(n, c, scope, normal)

-  var sinkParams = newSeq[PSym]()
-
  if owner.kind in {skProc, skFunc, skMethod, skIterator, skConverter}:
    let params = owner.typ.n
    for i in 1..<params.len:
      let t = params[i].sym.typ
-      if isSinkTypeForParam(t):
-        let baseType = t.skipTypes({tySink})
-        if baseType.kind in {tyString, tySequence, tyArray, tyTuple, tyObject}:
-          sinkParams.add params[i].sym
-        if hasDestructor(c, baseType):
-          scope.final.add c.genDestroy(params[i])
+      if isSinkTypeForParam(t) and hasDestructor(c, t.skipTypes({tySink})):
+        scope.final.add c.genDestroy(params[i])
  #if optNimV2 in c.graph.config.globalOptions:
  #  injectDefaultCalls(n, c)
  result = optimize processScope(c, scope, body)
-  if sinkParams.len > 0:
-    result = addSinkCopy(c, scope, sinkParams, result)
-
  dbg:
    echo ">---------transformed-to--------->"
    echo renderTree(result, {renderIds})
--- a/compiler/inliner.nim
+++ b/compiler/inliner.nim
@@ -1,122 +0,0 @@
-
-proc copySymdef(n: PNode; locals: var Table[int, PSym]; idgen: IdGenerator; owner: PSym): PNode =
-  case n.kind
-  of nkEmpty..pred(nkSym), succ(nkSym)..nkNilLit:
-    result = n
-  of nkSym:
-    let oldSym = n.sym
-    let newSym = copySym(oldSym, idgen)
-    setOwner(newSym, owner)
-    locals[oldSym.id] = newSym
-    result = newSymNode(newSym, oldSym.info)
-  else:
-    result = shallowCopy(n)
-    for i in 0..<n.len:
-      result[i] = copySymdef(n[i], locals, idgen, owner)
-
-proc copyInlineProcBody(n: PNode; locals: var Table[int, PSym]; idgen: IdGenerator; owner: PSym): PNode =
-  case n.kind
-  of nkEmpty..pred(nkSym), succ(nkSym)..nkNilLit:
-    result = n
-  of nkSym:
-    let sym = locals.getOrDefault(n.sym.id)
-    if sym != nil:
-      result = newSymNode(sym, n.info)
-    else:
-      result = n
-  of nkLetSection, nkVarSection:
-    result = shallowCopy(n)
-    for i in 0..<n.len:
-      let it = n[i]
-      if it.kind == nkCommentStmt:
-        result[i] = it
-      elif it.kind in {nkIdentDefs, nkConstDef}:
-        result[i] = shallowCopy(it)
-        for j in 0..<it.len-2:
-          result[i][j] = copySymdef(it[j], locals, idgen, owner)
-        for j in it.len-2..<it.len:
-          result[i][j] = copyInlineProcBody(it[j], locals, idgen, owner)
-      else:
-        assert it.kind == nkVarTuple
-        result[i] = shallowCopy(it)
-        for j in 0..<it.len-2:
-          assert it[j].kind == nkSym
-          let oldSym = it[j].sym
-          let newSym = copySym(oldSym, idgen)
-          setOwner(newSym, owner)
-          locals[oldSym.id] = newSym
-          result[i][j] = newSymNode(newSym, oldSym.info)
-        for j in it.len-2..<it.len:
-          result[i][j] = copyInlineProcBody(it[j], locals, idgen, owner)
-
-  of nkForStmt, nkParForStmt:
-    result = shallowCopy(n)
-    for i in 0..<n.len-2:
-      assert n[i].kind == nkSym
-      let oldSym = n[i].sym
-      let newSym = copySym(oldSym, idgen)
-      setOwner(newSym, owner)
-      locals[oldSym.id] = newSym
-      result[i] = newSymNode(newSym, oldSym.info)
-    result[n.len-2] = copyInlineProcBody(n[n.len-2], locals, idgen, owner)
-    result[n.len-1] = copyInlineProcBody(n[n.len-1], locals, idgen, owner)
-  of routineDefs, nkTypeSection, nkTypeOfExpr, nkMixinStmt, nkBindStmt, nkConstSection:
-    result = n
-  else:
-    result = shallowCopy(n)
-    for i in 0..<n.len:
-      result[i] = copyInlineProcBody(n[i], locals, idgen, owner)
-
-proc copyParams(n: PNode; locals: var Table[int, PSym]; idgen: IdGenerator; owner: PSym): PNode =
-  result = shallowCopy(n)
-  result[0] = n[0] # return type
-  for i in 1..<n.len:
-    let it = n[i]
-    assert it.kind == nkIdentDefs
-    result[i] = shallowCopy(it)
-    for j in 0..<it.len-2:
-      assert it[j].kind == nkSym
-      let oldSym = it[j].sym
-      let newSym = copySym(oldSym, idgen)
-      setOwner(newSym, owner)
-      locals[oldSym.id] = newSym
-      result[i][j] = newSymNode(newSym, oldSym.info)
-      owner.typ.addParam newSym
-    for j in it.len-2..<it.len:
-      result[i][j] = copyInlineProcBody(it[j], locals, idgen, owner)
-
-proc copyInlineProc(prc: PSym; idgen: IdGenerator): PSym =
-  result = copySym(prc, idgen)
-  var locals = initTable[int, PSym]()
-
-  var a = shallowCopy(prc.ast)
-  if resultPos < prc.ast.len and prc.ast[resultPos].kind == nkSym:
-    let oldRes = prc.ast[resultPos].sym
-    let newRes = copySym(oldRes, idgen)
-    setOwner(newRes, result)
-    locals[oldRes.id] = newRes
-    a[resultPos] = newSymNode(newRes, oldRes.info)
-
-  result.typ = copyType(prc.typ, idgen, result)
-  result.typ.n = newNodeI(prc.typ.n.kind, prc.typ.n.info)
-  if prc.typ.n.len > 0:
-    result.typ.n.add copyNode(prc.typ.n[0])
-    for i in 1..<prc.typ.n.len:
-      let it = prc.typ.n[i]
-      assert it.kind == nkSym
-      let oldSym = it.sym
-      let newSym = copySym(oldSym, idgen)
-      setOwner(newSym, result)
-      locals[oldSym.id] = newSym
-      result.typ.addParam newSym
-
-  for i in 0..<prc.ast.len:
-    if i == paramsPos:
-      a[i] = copyTree(prc.ast[i])
-    elif i == resultPos and prc.ast[i].kind == nkSym:
-      discard "handled above"
-    else:
-      a[i] = copyInlineProcBody(prc.ast[i], locals, idgen, result)
-  result.ast = a
-
-  #echo "Produced: ", renderTree(result.ast, {renderIds})
--- a/compiler/installer.ini
+++ b/compiler/installer.ini
@@ -6,11 +6,11 @@ Name: "Nim"
 Version: "$version"
 Platforms: """
  windows: i386;amd64
-  linux: i386;hppa;ia64;alpha;amd64;powerpc64;arm;sparc;sparc64;s390x;m68k;mips;mipsel;mips64;mips64el;powerpc;powerpc64el;arm64;riscv32;riscv64;loongarch64
+  linux: i386;hppa;ia64;alpha;amd64;powerpc64;arm;sparc;sparc64;m68k;mips;mipsel;mips64;mips64el;powerpc;powerpc64el;arm64;riscv32;riscv64
  macosx: i386;amd64;powerpc64;arm64
  solaris: i386;amd64;sparc;sparc64
  freebsd: i386;amd64;powerpc64;arm;arm64;riscv64;sparc64;mips;mipsel;mips64;mips64el;powerpc;powerpc64el
-  netbsd: i386;amd64;arm64
+  netbsd: i386;amd64
  openbsd: i386;amd64;arm;arm64
  dragonfly: i386;amd64
  crossos: amd64
@@ -71,7 +71,6 @@ Files: "testament"
 Files: "nimsuggest"
 Files: "nimsuggest/tests/*.nim"
 Files: "changelogs/*.md"
-Files: "ci/funs.sh"

 [Lib]
 Files: "lib"
@@ -80,7 +79,6 @@ Files: "lib"
 Files: "examples"
 Files: "dist/nimble"
 Files: "dist/checksums"
-Files: "dist/nimony"

 Files: "tests"

@@ -148,4 +146,4 @@ licenses: "bin/nim,MIT;lib/*,MIT;"

 [nimble]
 pkgName: "nim"
-pkgFiles: "compiler/*;doc/basicopt.txt;doc/advopt.txt;doc/nimdoc.css;doc/nimdoc.cls"
+pkgFiles: "compiler/*;doc/basicopt.txt;doc/advopt.txt;doc/nimdoc.css"
--- a/compiler/int128.nim
+++ b/compiler/int128.nim
@@ -3,7 +3,7 @@
 ## hold all from `low(BiggestInt)` to `high(BiggestUInt)`, This
 ## type is for that purpose.

-from std/math import trunc
+from math import trunc

 when defined(nimPreviewSlimSystem):
  import std/assertions
@@ -34,7 +34,6 @@ 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:
@@ -209,35 +208,30 @@ 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
@@ -264,7 +258,6 @@ 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
@@ -288,7 +281,6 @@ 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)
@@ -321,7 +313,6 @@ 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)
@@ -344,7 +335,6 @@ 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)
@@ -368,7 +358,7 @@ proc `*`*(lhs, rhs: Int128): Int128 =
 proc `*=`*(a: var Int128, b: Int128) =
  a = a * b

-import std/bitops
+import bitops

 proc fastLog2*(a: Int128): int =
  result = 0
@@ -383,8 +373,6 @@ 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)

@@ -551,28 +539,24 @@ 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
--- a/compiler/isolation_check.nim
+++ b/compiler/isolation_check.nim
@@ -11,9 +11,7 @@
 ## https://github.com/nim-lang/RFCs/issues/244 for more details.

 import
-  ast, types, renderer
-
-import std/intsets
+  ast, types, renderer, intsets

 when defined(nimPreviewSlimSystem):
  import std/assertions
@@ -54,18 +52,18 @@ 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.baseClass != nil:
-        result = canAlias(arg, ret.baseClass, marker)
+      if not result and ret.len > 0 and ret[0] != nil:
+        result = canAlias(arg, ret[0], marker)
    else:
      result = true
  of tyTuple:
    result = false
-    for r in ret.kids:
-      result = canAlias(arg, r, marker)
+    for i in 0..<ret.len:
+      result = canAlias(arg, ret[i], marker)
      if result: break
  of tyArray, tySequence, tyDistinct, tyGenericInst,
     tyAlias, tyInferred, tySink, tyLent, tyOwned, tyRef:
-    result = canAlias(arg, ret.skipModifier, marker)
+    result = canAlias(arg, ret.lastSon, marker)
  of tyProc:
    result = ret.callConv == ccClosure
  else:
@@ -119,16 +117,14 @@ proc containsDangerousRefAux(t: PType; marker: var IntSet): SearchResult =
  if result != NotFound: return result
  case t.kind
  of tyObject:
-    if t.baseClass != nil:
-      result = containsDangerousRefAux(t.baseClass.skipTypes(skipPtrs), marker)
+    if t[0] != nil:
+      result = containsDangerousRefAux(t[0].skipTypes(skipPtrs), marker)
    if result == NotFound: result = containsDangerousRefAux(t.n, marker)
  of tyGenericInst, tyDistinct, tyAlias, tySink:
-    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)
+    result = containsDangerousRefAux(lastSon(t), marker)
+  of tyArray, tySet, tyTuple, tySequence:
+    for i in 0..<t.len:
+      result = containsDangerousRefAux(t[i], marker)
      if result == Found: return result
  else:
    discard
@@ -166,7 +162,7 @@ proc containsVariable(n: PNode): bool =
 proc checkIsolate*(n: PNode): bool =
  if types.containsTyRef(n.typ):
    # XXX Maybe require that 'n.typ' is acyclic. This is not much
-    # worse than the already existing inheritance and closure restrictions.
+    # worse than the already exisiting inheritance and closure restrictions.
    case n.kind
    of nkCharLit..nkNilLit:
      result = true
--- a/compiler/jsgen.nim
+++ b/compiler/jsgen.nim
--- a/compiler/jstypes.nim
+++ b/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.baseClass != nil
+  tfInheritable in t.flags or t[0] != 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.baseClass != nil):
+  if (typ.kind == tyObject) and (typ[0] != nil):
    p.g.typeInfo.addf("$1.base = $2;$n",
-         [name, genTypeInfo(p, typ.baseClass.skipTypes(skipPtrs))])
+         [name, genTypeInfo(p, typ[0].skipTypes(skipPtrs))])

 proc genTupleFields(p: PProc, typ: PType): Rope =
  var s: Rope = ""
@@ -117,17 +117,17 @@ 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.baseClass != nil:
+  if typ[0] != nil:
    p.g.typeInfo.addf("$1.base = $2;$n",
-         [name, genTypeInfo(p, typ.baseClass)])
+         [name, genTypeInfo(p, typ[0])])

 proc genTypeInfo(p: PProc, typ: PType): Rope =
-  let t = typ.skipTypes({tyGenericInst, tyDistinct, tyAlias, tySink, tyOwned} + tyUserTypeClasses)
+  let t = typ.skipTypes({tyGenericInst, tyDistinct, tyAlias, tySink, tyOwned})
  result = "NTI$1" % [rope(t.id)]
  if containsOrIncl(p.g.typeInfoGenerated, t.id): return
  case t.kind
  of tyDistinct:
-    result = genTypeInfo(p, t.skipModifier)
+    result = genTypeInfo(p, t[0])
  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.elementType)])
+         [result, genTypeInfo(p, t.lastSon)])
  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.elementType)])
+         [result, genTypeInfo(p, t[1])])
  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, skipModifier t)
+    if t.n != nil: result = genTypeInfo(p, lastSon t)
    else: internalError(p.config, "genTypeInfo(" & $t.kind & ')')
  else: internalError(p.config, "genTypeInfo(" & $t.kind & ')')
--- a/compiler/lambdalifting.nim
+++ b/compiler/lambdalifting.nim
@@ -10,12 +10,10 @@
 # This file implements lambda lifting for the transformator.

 import
-  options, ast, astalgo, msgs,
-  idents, renderer, types, magicsys, lowerings, modulegraphs, lineinfos,
+  intsets, strutils, options, ast, astalgo, msgs,
+  idents, renderer, types, magicsys, lowerings, tables, modulegraphs, lineinfos,
  transf, liftdestructors, typeallowed

-import std/[strutils, tables, intsets]
-
 when defined(nimPreviewSlimSystem):
  import std/assertions

@@ -135,24 +133,21 @@ 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, idgen, iter)
+  result = newType(tyRange, nextTypeId(idgen), iter)
  result.n = n
  var intType = nilOrSysInt(g)
-  if intType.isNil: intType = newType(tyInt, idgen, iter)
+  if intType.isNil: intType = newType(tyInt, nextTypeId(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)
-  result.incl tfFinal
-  if owner.isIterator:
-    rawAddField(result, createStateField(g, owner, idgen))
+  rawAddField(result, createStateField(g, owner, idgen))

 proc getClosureIterResult*(g: ModuleGraph; iter: PSym; idgen: IdGenerator): PSym =
  if resultPos < iter.ast.len:
@@ -160,8 +155,8 @@ 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.returnType
-    incl(result.flagsImpl, sfUsed)
+    result.typ = iter.typ[0]
+    incl(result.flags, sfUsed)
    iter.ast.add newSymNode(result)

 proc addHiddenParam(routine: PSym, param: PSym) =
@@ -175,23 +170,26 @@ proc addHiddenParam(routine: PSym, param: PSym) =
  assert sfFromGeneric in param.flags
  #echo "produced environment: ", param.id, " for ", routine.id

-proc getEnvParam*(routine: PSym): PSym =
-  if routine.ast.isNil: return nil
+proc getHiddenParam(g: ModuleGraph; routine: PSym): PSym =
  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
+  else:
+    result = nil
+
 proc interestingVar(s: PSym): bool {.inline.} =
  result = s.kind in {skVar, skLet, skTemp, skForVar, skParam, skResult} and
    sfGlobal notin s.flags and
@@ -200,7 +198,7 @@ proc interestingVar(s: PSym): bool {.inline.} =
 proc illegalCapture(s: PSym): bool {.inline.} =
  result = classifyViewType(s.typ) != noView or s.kind == skResult

-proc isInnerProc*(s: PSym): bool =
+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:
@@ -228,19 +226,28 @@ proc makeClosure*(g: ModuleGraph; idgen: IdGenerator; prc: PSym; env: PNode; inf
  #if isClosureIterator(result.typ):
  createTypeBoundOps(g, nil, result.typ, info, idgen)
  if tfHasAsgn in result.typ.flags or optSeqDestructors in g.config.globalOptions:
-    prc.incl sfInjectDestructors
+    prc.flags.incl sfInjectDestructors

-template liftingHarmful(conf: ConfigRef; owner: PSym): bool =
+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.} =
  ## lambda lifting can be harmful for JS-like code generators.
  let isCompileTime = sfCompileTime in owner.flags or owner.kind == skMacro
-  jsNoLambdaLifting in conf.legacyFeatures and conf.backend == backendJs and not isCompileTime
+  result = 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.elementType, info, idgen)
+    createTypeBoundOps(g, nil, refType.lastSon, info, idgen)
    createTypeBoundOps(g, nil, refType, info, idgen)
    if tfHasAsgn in refType.flags or optSeqDestructors in g.config.globalOptions:
-      owner.incl sfInjectDestructors
+      owner.flags.incl sfInjectDestructors

 proc genCreateEnv(env: PNode): PNode =
  var c = newNodeIT(nkObjConstr, env.info, env.typ)
@@ -255,7 +262,8 @@ proc liftIterSym*(g: ModuleGraph; n: PNode; idgen: IdGenerator; owner: PSym): PN
  let iter = n.sym
  assert iter.isIterator

-  result = newNodeIT(nkStmtListExpr, n.info, iter.typ)
+  result = newNodeIT(nkStmtListExpr, n.info, n.typ)
+
  let hp = getHiddenParam(g, iter)
  var env: PNode
  if owner.isIterator:
@@ -276,6 +284,15 @@ 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) =
@@ -285,12 +302,12 @@ 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: $3; using '-d:nimNoLentIterators' helps in some cases." &
-       " Consider using a <ref T> which can be captured.") %
-      [s.name.s, typeToString(s.typ.skipTypes({tyVar})), g.config$s.info])
+       " Consider using a <ref $2> which can be captured.") %
+      [s.name.s, typeToString(s.typ), g.config$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])
-  incl(owner.typ, tfCapturesEnv)
+  incl(owner.typ.flags, tfCapturesEnv)
  if not isEnv:
    owner.typ.callConv = ccClosure

@@ -323,20 +340,16 @@ proc getEnvTypeForOwner(c: var DetectionPass; owner: PSym;
                        info: TLineInfo): PType =
  result = c.ownerToType.getOrDefault(owner.id)
  if result.isNil:
-    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
+    result = newType(tyRef, nextTypeId(c.idgen), owner)
+    let obj = createEnvObj(c.graph, c.idgen, owner, info)
+    rawAddSon(result, obj)
    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, c.idgen, t.owner)
-    result.incl tfHasOwned
+    result = newType(tyOwned, nextTypeId(c.idgen), t.owner)
+    result.flags.incl tfHasOwned
    result.rawAddSon t
  else:
    result = t
@@ -344,7 +357,7 @@ 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, c.idgen, owner)
+  result = newType(tyPtr, nextTypeId(c.idgen), owner)
  rawAddSon(result, r.skipTypes({tyOwned, tyRef, tyPtr}))

 proc createUpField(c: var DetectionPass; dest, dep: PSym; info: TLineInfo) =
@@ -414,19 +427,13 @@ proc addClosureParam(c: var DetectionPass; fn: PSym; info: TLineInfo) =
  let t = c.getEnvTypeForOwner(owner, info)
  if cp == nil:
    cp = newSym(skParam, getIdent(c.graph.cache, paramName), c.idgen, fn, fn.info)
-    incl(cp.flagsImpl, sfFromGeneric)
+    incl(cp.flags, sfFromGeneric)
    cp.typ = t
    addHiddenParam(fn, cp)
  elif cp.typ != t and fn.kind != skIterator:
    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:
@@ -442,15 +449,25 @@ 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 or iterEnvHasUpField(c.graph, s))
+    let innerClosure = innerProc and s.typ.callConv == ccClosure and not s.isIterator
    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 """
@@ -532,8 +549,8 @@ 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:
@@ -541,7 +558,6 @@ 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

@@ -553,7 +569,7 @@ 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.elementType, v)
+      addUniqueField(it.typ[0], v)
      result = indirectAccess(newSymNode(it), v, v.info)
    else:
      result = newSymNode(v)
@@ -624,7 +640,7 @@ proc rawClosureCreation(owner: PSym;
        if owner.kind != skMacro:
          createTypeBoundOps(d.graph, nil, fieldAccess.typ, env.info, d.idgen)
        if tfHasAsgn in fieldAccess.typ.flags or optSeqDestructors in d.graph.config.globalOptions:
-          owner.incl sfInjectDestructors
+          owner.flags.incl sfInjectDestructors

  let upField = lookupInRecord(env.typ.skipTypes({tyOwned, tyRef, tyPtr}).n, getIdent(d.graph.cache, upName))
  if upField != nil:
@@ -650,27 +666,16 @@ 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 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;
+proc closureCreationForIter(iter: PNode;
                            d: var DetectionPass; c: var LiftingPass): PNode =
  result = newNodeIT(nkStmtListExpr, iter.info, iter.sym.typ)
-  let iterOwner = iter.sym.skipGenericOwner
-  var v = newSym(skVar, getIdent(d.graph.cache, envName), d.idgen, iterOwner, iter.info)
-  incl(v.flagsImpl, sfShadowed)
+  let owner = iter.sym.skipGenericOwner
+  var v = newSym(skVar, getIdent(d.graph.cache, envName), d.idgen, owner, iter.info)
+  incl(v.flags, sfShadowed)
  v.typ = asOwnedRef(d, getHiddenParam(d.graph, iter.sym).typ)
  var vnode: PNode
-  if iterOwner.isIterator:
-    let it = getHiddenParam(d.graph, iterOwner)
+  if owner.isIterator:
+    let it = getHiddenParam(d.graph, owner)
    addUniqueField(it.typ.skipTypes({tyOwned, tyRef, tyPtr}), v, d.graph.cache, d.idgen)
    vnode = indirectAccess(newSymNode(it), v, v.info)
  else:
@@ -679,14 +684,12 @@ proc closureCreationForIter(owner: PSym, iter: PNode;
    addVar(vs, vnode)
    result.add(vs)
  result.add genCreateEnv(vnode)
-  createTypeBoundOpsLL(d.graph, vnode.typ, iter.info, d.idgen, iterOwner)
+  createTypeBoundOpsLL(d.graph, vnode.typ, iter.info, d.idgen, owner)

  let upField = lookupInRecord(v.typ.skipTypes({tyOwned, tyRef, tyPtr}).n, getIdent(d.graph.cache, upName))
  if upField != nil:
-    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:
+    let u = setupEnvVar(owner, d, c, iter.info)
+    if u.typ.skipTypes({tyOwned, tyRef, tyPtr}) == upField.typ.skipTypes({tyOwned, tyRef, tyPtr}):
      result.add(newAsgnStmt(rawIndirectAccess(vnode, upField, iter.info),
                 u, iter.info))
    else:
@@ -720,7 +723,7 @@ 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(owner, n, d, c)
+    result = closureCreationForIter(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)
@@ -752,7 +755,7 @@ 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, {})
+        var body = transformBody(d.graph, d.idgen, s, dontUseCache)
        body = liftCapturedVars(body, s, d, c)
        if c.envVars.getOrDefault(s.id).isNil:
          s.transformedBody = body
@@ -767,6 +770,8 @@ 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,
@@ -874,19 +879,20 @@ 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; flags: TransformFlags): PNode =
+                  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.
  let isCompileTime = sfCompileTime in fn.flags or fn.kind == skMacro

-  if body.kind == nkEmpty or (jsNoLambdaLifting in g.config.legacyFeatures and
+  if body.kind == nkEmpty or (
      g.config.backend == backendJs and not isCompileTime) or
-      (fn.skipGenericOwner.kind != skModule and force notin flags):
+      (fn.skipGenericOwner.kind != skModule and not force):

    # 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)
@@ -975,20 +981,6 @@ proc liftForLoop*(g: ModuleGraph; body: PNode; idgen: IdGenerator; owner: PSym):
      for i in 0..<op.len-1:
        result.add op[i]

-  elif op.kind != nkSym: # might have side effects
-    # bug #25046
-    # create a temp for the closure
-    # var :closureTemp
-    # :closureTemp = ...
-    let tempSym = newSym(skLet, getIdent(g.cache, ":closureTemp"), idgen, owner, body.info)
-    tempSym.typ = call[0].typ
-    let temp = newSymNode(tempSym)
-    var v = newNodeI(nkVarSection, body.info)
-    addVar(v, temp)
-    result.add(v)
-    result.add newAsgnStmt(temp, call[0], body.info)
-    call[0] = temp
-
  var loopBody = newNodeI(nkStmtList, body.info, 3)
  var whileLoop = newNodeI(nkWhileStmt, body.info, 2)
  whileLoop[0] = newIntTypeNode(1, getSysType(g, body.info, tyBool))
@@ -999,15 +991,12 @@ proc liftForLoop*(g: ModuleGraph; body: PNode; idgen: IdGenerator; owner: PSym):
  # gather vars in a tuple:
  var v2 = newNodeI(nkLetSection, body.info)
  var vpart = newNodeI(if body.len == 3: nkIdentDefs else: nkVarTuple, body.info)
-  if body.len == 3 and body[0].kind == nkVarTuple:
-    vpart = body[0] # fixes for (i,j) in walk() # bug #15924
-  else:
-    for i in 0..<body.len-2:
-      if body[i].kind == nkSym:
-        body[i].sym.transitionToLet()
-      vpart.add body[i]
+  for i in 0..<body.len-2:
+    if body[i].kind == nkSym:
+      body[i].sym.transitionToLet()
+    vpart.add body[i]

-    vpart.add newNodeI(nkEmpty, body.info) # no explicit type
+  vpart.add newNodeI(nkEmpty, body.info) # no explicit type
  if not env.isNil:
    call[0] = makeClosure(g, idgen, call[0].sym, env.newSymNode, body.info)
  vpart.add call
--- a/compiler/layeredtable.nim
+++ b/compiler/layeredtable.nim
@@ -1,91 +0,0 @@
-import ast, astalgo
-
-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)
-  #copyIdTable(result.topLayer, pt.topLayer)
-
-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.counter
-
-proc newTypeMapLayer*(pt: LayeredIdTable): LayeredIdTable =
-  result = LayeredIdTable(topLayer: initTypeMapping(), 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
-
-iterator pairs*(pt: LayeredIdTable): (ItemId, PType) =
-  var tm = pt
-  while true:
-    for (k, v) in idTablePairs(tm.topLayer):
-      yield (k, v)
-    if tm.nextLayer == nil:
-      break
-    tm.setToPreviousLayer
-
-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)
--- a/compiler/layouter.nim
+++ b/compiler/layouter.nim
@@ -9,7 +9,7 @@

 ## Layouter for nimpretty.

-import idents, lexer, ast, lineinfos, llstream, options, msgs, strutils, pathutils
+import idents, lexer, lineinfos, llstream, options, msgs, strutils, pathutils

 const
  MinLineLen = 15
@@ -243,28 +243,23 @@ proc renderTokens*(em: var Emitter): string =

  return content

-type
-  FinalCheck = proc (content: string; origAst: PNode): bool {.nimcall.}
-
-proc writeOut*(em: Emitter; content: string; origAst: PNode; check: FinalCheck) =
+proc writeOut*(em: Emitter, content: string)  =
  ## 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)

-  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) =
+proc closeEmitter*(em: var Emitter) =
  ## Renders emitter tokens and write to a file
  let content = renderTokens(em)
-  em.writeOut(content, origAst, check)
+  em.writeOut(content)

 proc wr(em: var Emitter; x: string; lt: LayoutToken) =
  em.tokens.add x
--- a/compiler/lexer.nim
+++ b/compiler/lexer.nim
@@ -16,10 +16,8 @@
 # DOS or Macintosh text files, even when it is not the native format.

 import
-  options, msgs, platform, idents, nimlexbase, llstream,
-  wordrecg, lineinfos, pathutils
-
-import std/[hashes, parseutils, strutils]
+  hashes, options, msgs, strutils, platform, idents, nimlexbase, llstream,
+  wordrecg, lineinfos, pathutils, parseutils

 when defined(nimPreviewSlimSystem):
  import std/[assertions, formatfloat]
@@ -122,6 +120,7 @@ type
                              # this is needed because scanning comments
                              # needs so much look-ahead
    currLineIndent*: int
+    strongSpaces*, allowTabs*: bool
    errorHandler*: ErrorHandler
    cache*: IdentCache
    when defined(nimsuggest):
@@ -175,6 +174,32 @@ 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)
@@ -300,7 +325,8 @@ 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(literal: "")
+    var t: Token
+    t.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
@@ -770,7 +796,7 @@ proc getString(L: var Lexer, tok: var Token, mode: StringMode) =
    if mode != normal: tok.tokType = tkRStrLit
    else: tok.tokType = tkStrLit
    while true:
-      let c = L.buf[pos]
+      var c = L.buf[pos]
      if c == '\"':
        if mode != normal and L.buf[pos+1] == '\"':
          inc(pos, 2)
@@ -796,7 +822,7 @@ proc getCharacter(L: var Lexer; tok: var Token) =
  tokenBegin(tok, L.bufpos)
  let startPos = L.bufpos
  inc(L.bufpos)               # skip '
-  let c = L.buf[L.bufpos]
+  var c = L.buf[L.bufpos]
  case c
  of '\0'..pred(' '), '\'':
    lexMessage(L, errGenerated, "invalid character literal")
@@ -914,7 +940,7 @@ proc getOperator(L: var Lexer, tok: var Token) =
  tokenBegin(tok, pos)
  var h: Hash = 0
  while true:
-    let c = L.buf[pos]
+    var c = L.buf[pos]
    if c in OpChars:
      h = h !& ord(c)
      inc(pos)
@@ -982,6 +1008,23 @@ proc getPrecedence*(tok: Token): int =
  of tkOr, tkXor, tkPtr, tkRef: result = 3
  else: return -10

+proc newlineFollows*(L: Lexer): bool =
+  result = false
+  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
@@ -1073,7 +1116,9 @@ 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)
@@ -1116,7 +1161,7 @@ proc skip(L: var Lexer, tok: var Token) =
      inc(pos)
      tok.spacing.incl(tsLeading)
    of '\t':
-      lexMessagePos(L, errGenerated, pos, "tabs are not allowed, use spaces instead")
+      if not L.allowTabs: lexMessagePos(L, errGenerated, pos, "tabs are not allowed, use spaces instead")
      inc(pos)
    of CR, LF:
      tokenEndPrevious(tok, pos)
@@ -1184,7 +1229,7 @@ proc rawGetTok*(L: var Lexer, tok: var Token) =
        L.previousToken.line = tok.line.uint16
        L.previousToken.col = tok.col.int16

-  reset(tok)
+  fillToken(tok)
  if L.indentAhead >= 0:
    tok.indent = L.indentAhead
    L.currLineIndent = L.indentAhead
@@ -1196,7 +1241,7 @@ proc rawGetTok*(L: var Lexer, tok: var Token) =
    if tok.tokType == tkComment:
      L.indentAhead = L.currLineIndent
      return
-  let c = L.buf[L.bufpos]
+  var c = L.buf[L.bufpos]
  tok.line = L.lineNumber
  tok.col = getColNumber(L, L.bufpos)
  if c in SymStartChars - {'r', 'R'} - UnicodeOperatorStartChars:
@@ -1355,6 +1400,7 @@ proc getIndentWidth*(fileIdx: FileIndex, inputstream: PLLStream;
  result = 0
  var lex: Lexer = default(Lexer)
  var tok: Token = default(Token)
+  initToken(tok)
  openLexer(lex, fileIdx, inputstream, cache, config)
  var prevToken = tkEof
  while tok.tokType != tkEof:
@@ -1367,11 +1413,11 @@ proc getIndentWidth*(fileIdx: FileIndex, inputstream: PLLStream;

 proc getPrecedence*(ident: PIdent): int =
  ## assumes ident is binary operator already
-  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)
-
+  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
  getPrecedence(tok)
--- a/compiler/liftdestructors.nim
+++ b/compiler/liftdestructors.nim
@@ -11,9 +11,8 @@
 ## (`=sink`, `=copy`, `=destroy`, `=deepCopy`, `=wasMoved`, `=dup`).

 import modulegraphs, lineinfos, idents, ast, renderer, semdata,
-  sighashes, lowerings, options, types, msgs, magicsys, ccgutils
+  sighashes, lowerings, options, types, msgs, magicsys, tables, ccgutils

-import std/tables
 from trees import isCaseObj

 when defined(nimPreviewSlimSystem):
@@ -56,10 +55,10 @@ proc destructorOverridden(g: ModuleGraph; t: PType): bool =
  op != nil and sfOverridden in op.flags

 proc fillBodyTup(c: var TLiftCtx; t: PType; body, x, y: PNode) =
-  for i, a in t.ikids:
+  for i in 0..<t.len:
    let lit = lowerings.newIntLit(c.g, x.info, i)
-    let b = if c.kind == attachedTrace: y else: y.at(lit, a)
-    fillBody(c, a, body, x.at(lit, a), b)
+    let b = if c.kind == attachedTrace: y else: y.at(lit, t[i])
+    fillBody(c, t[i], body, x.at(lit, t[i]), b)

 proc dotField(x: PNode, f: PSym): PNode =
  result = newNodeI(nkDotExpr, x.info, 2)
@@ -91,7 +90,7 @@ proc defaultOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
    call.typ = t
    body.add newAsgnStmt(x, call)
  elif c.kind == attachedWasMoved:
-    body.add genBuiltin(c, mWasMoved, "wasMoved", x)
+    body.add genBuiltin(c, mWasMoved, "`=wasMoved`", x)

 proc genAddr(c: var TLiftCtx; x: PNode): PNode =
  if x.kind == nkHiddenDeref:
@@ -139,25 +138,25 @@ 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.returnType)
+  var destroy = newNodeIT(nkCall, x.info, op.typ[0])
  destroy.add(newSymNode(op))
-  if op.typ.firstParamType.kind != tyVar:
+  if op.typ[1].kind != tyVar:
    destroy.add x
  else:
    destroy.add genAddr(c, x)
  if sfNeverRaises notin op.flags:
    c.canRaise = true
  if c.addMemReset:
-    result = newTree(nkStmtList, destroy, genBuiltin(c, mWasMoved,  "wasMoved", x))
+    result = newTree(nkStmtList, destroy, genBuiltin(c, mWasMoved,  "`=wasMoved`", x))
  else:
    result = destroy

 proc genWasMovedCall(c: var TLiftCtx; op: PSym; x: PNode): PNode =
-  result = newNodeIT(nkCall, x.info, op.typ.returnType)
+  result = newNodeIT(nkCall, x.info, op.typ[0])
  result.add(newSymNode(op))
  result.add genAddr(c, x)

-proc fillBodyObj(c: var TLiftCtx; n, body, x, y: PNode; enforceDefaultOp: bool, enforceWasMoved = false) =
+proc fillBodyObj(c: var TLiftCtx; n, body, x, y: PNode; enforceDefaultOp: bool) =
  case n.kind
  of nkSym:
    if c.filterDiscriminator != nil: return
@@ -167,8 +166,6 @@ proc fillBodyObj(c: var TLiftCtx; n, body, x, y: PNode; enforceDefaultOp: bool,
        enforceDefaultOp:
      defaultOp(c, f.typ, body, x.dotField(f), b)
    else:
-      if enforceWasMoved:
-        body.add genBuiltin(c, mWasMoved, "wasMoved", x.dotField(f))
      fillBody(c, f.typ, body, x.dotField(f), b)
  of nkNilLit: discard
  of nkRecCase:
@@ -207,7 +204,7 @@ proc fillBodyObj(c: var TLiftCtx; n, body, x, y: PNode; enforceDefaultOp: bool,
      branch[^1] = newNodeI(nkStmtList, c.info)

      fillBodyObj(c, n[i].lastSon, branch[^1], x, y,
-                  enforceDefaultOp = localEnforceDefaultOp, enforceWasMoved = c.kind == attachedAsgn)
+                  enforceDefaultOp = localEnforceDefaultOp)
      if branch[^1].len == 0: inc emptyBranches
      caseStmt.add(branch)
    if emptyBranches != n.len-1:
@@ -218,44 +215,20 @@ proc fillBodyObj(c: var TLiftCtx; n, body, x, y: PNode; enforceDefaultOp: bool,
      fillBodyObj(c, n[0], body, x, y, enforceDefaultOp = false)
    c.filterDiscriminator = oldfilterDiscriminator
  of nkRecList:
-    # destroys in reverse order #24719
-    if c.kind == attachedDestructor:
-      for i in countdown(n.len-1, 0):
-        fillBodyObj(c, n[i], body, x, y, enforceDefaultOp, enforceWasMoved)
-    else:
-      for t in items(n): fillBodyObj(c, t, body, x, y, enforceDefaultOp, enforceWasMoved)
+    for t in items(n): fillBodyObj(c, t, body, x, y, enforceDefaultOp)
  else:
    illFormedAstLocal(n, c.g.config)

 proc fillBodyObjTImpl(c: var TLiftCtx; t: PType, body, x, y: PNode) =
-  template fillBase =
-    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)
-  template fillFields =
-    fillBodyObj(c, t.n, body, x, y, enforceDefaultOp = false)
-
-  if c.kind == attachedDestructor:
-    # destroys in reverse order #24719
-    fillFields()
-    fillBase()
-  else:
-    fillBase()
-    fillFields()
+  if t.len > 0 and t[0] != nil:
+    fillBody(c, skipTypes(t[0], abstractPtrs), body, x, y)
+  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.baseClass != nil:
-    obj = skipTypes(obj.baseClass, abstractPtrs)
+  while obj.len > 0 and obj[0] != nil:
+    obj = skipTypes(obj[0], abstractPtrs)
    hasCase = hasCase or isCaseObj(obj.n)

  if hasCase and c.kind in {attachedAsgn, attachedDeepCopy}:
@@ -284,7 +257,7 @@ proc fillBodyObjT(c: var TLiftCtx; t: PType, body, x, y: PNode) =
      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
-    incl(temp, sfFromGeneric)
+    incl(temp.flags, sfFromGeneric)
    var v = newNodeI(nkVarSection, c.info)
    let blob = newSymNode(temp)
    v.addVar(blob, x)
@@ -292,8 +265,7 @@ proc fillBodyObjT(c: var TLiftCtx; t: PType, body, x, y: PNode) =
    #body.add newAsgnStmt(blob, x)

    var wasMovedCall = newNodeI(nkCall, c.info)
-    wasMovedCall.add(newSymNode(createMagic(c.g, c.idgen, "wasMoved", mWasMoved)))
-
+    wasMovedCall.add(newSymNode(createMagic(c.g, c.idgen, "`=wasMoved`", mWasMoved)))
    wasMovedCall.add x # mWasMoved does not take the address
    body.add wasMovedCall

@@ -306,7 +278,6 @@ proc fillBodyObjT(c: var TLiftCtx; t: PType, body, x, y: PNode) =
    c.kind = attachedDestructor
    fillBodyObjTImpl(c, t, body, blob, y)
    c.kind = prevKind
-
  else:
    fillBodyObjTImpl(c, t, body, x, y)

@@ -316,7 +287,7 @@ proc boolLit*(g: ModuleGraph; info: TLineInfo; value: bool): PNode =

 proc getCycleParam(c: TLiftCtx): PNode =
  assert c.kind in {attachedAsgn, attachedDup}
-  if c.fn.typ.len == 3 + ord(c.kind == attachedAsgn):
+  if c.fn.typ.len == 4:
    result = c.fn.typ.n.lastSon
    assert result.kind == nkSym
    assert result.sym.name.s == "cyclic"
@@ -330,35 +301,27 @@ 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.firstParamType.kind == tyVar:
+  if op.typ[1].kind == tyVar:
    result.add genAddr(c, x)
  else:
    result.add x
  if y != nil:
    result.add y
-  if op.typ.signatureLen == 4:
+  if op.typ.len == 4:
    assert y != nil
-    if c.fn.typ.signatureLen == 4:
+    if c.fn.typ.len == 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.returnType)
+  result = newNodeIT(nkCall, x.info, op.typ[0])
  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))

@@ -380,10 +343,6 @@ proc requiresDestructor(c: TLiftCtx; t: PType): bool {.inline.} =
 proc instantiateGeneric(c: var TLiftCtx; op: PSym; t, typeInst: PType): PSym =
  if c.c != nil and typeInst != nil:
    result = c.c.instTypeBoundOp(c.c, op, typeInst, c.info, attachedAsgn, 1)
-  elif typeInst != nil and getAttachedOp(c.g, typeInst, c.kind) != nil:
-    # c.c == nil in lambdalifting
-    # hooks are already insted
-    result = getAttachedOp(c.g, typeInst, c.kind)
  else:
    localError(c.g.config, c.info,
      "cannot generate destructor for generic type: " & typeToString(t))
@@ -397,8 +356,7 @@ proc considerAsgnOrSink(c: var TLiftCtx; t: PType; body, x, y: PNode;
    if op != nil and op != c.fn and
        (sfOverridden in op.flags or destructorOverridden):
      if sfError in op.flags:
-        ensureMutable c.fn
-        incl c.fn.flagsImpl, sfError
+        incl c.fn.flags, sfError
      #else:
      #  markUsed(c.g.config, c.info, op, c.g.usageSym)
      onUse(c.info, op)
@@ -424,8 +382,7 @@ proc considerAsgnOrSink(c: var TLiftCtx; t: PType; body, x, y: PNode;
      if op == nil:
        op = produceSym(c.g, c.c, t, c.kind, c.info, c.idgen)
    if sfError in op.flags:
-      ensureMutable c.fn
-      incl c.fn.flagsImpl, sfError
+      incl c.fn.flags, sfError
    #else:
    #  markUsed(c.g.config, c.info, op, c.g.usageSym)
    onUse(c.info, op)
@@ -541,7 +498,7 @@ proc considerUserDefinedOp(c: var TLiftCtx; t: PType; body, x, y: PNode): bool =
 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)
  temp.typ = getSysType(c.g, body.info, tyInt)
-  incl(temp.flagsImpl, sfFromGeneric)
+  incl(temp.flags, sfFromGeneric)

  var v = newNodeI(nkVarSection, c.info)
  result = newSymNode(temp)
@@ -551,7 +508,7 @@ proc declareCounter(c: var TLiftCtx; body: PNode; first: BiggestInt): PNode =
 proc declareTempOf(c: var TLiftCtx; body: PNode; value: PNode): PNode =
  var temp = newSym(skTemp, getIdent(c.g.cache, lowerings.genPrefix), c.idgen, c.fn, c.info)
  temp.typ = value.typ
-  incl(temp.flagsImpl, sfFromGeneric)
+  incl(temp.flags, sfFromGeneric)

  var v = newNodeI(nkVarSection, c.info)
  result = newSymNode(temp)
@@ -587,7 +544,7 @@ 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.elementType
+  let elemType = t.lastSon
  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:
@@ -634,7 +591,7 @@ proc fillSeqOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
    if canFormAcycle(c.g, t.elemType):
      # follow all elements:
      forallElements(c, t, body, x, y)
-  of attachedWasMoved: body.add genBuiltin(c, mWasMoved, "wasMoved", x)
+  of attachedWasMoved: body.add genBuiltin(c, mWasMoved, "`=wasMoved`", x)

 proc useSeqOrStrOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
  createTypeBoundOps(c.g, c.c, t, body.info, c.idgen)
@@ -672,7 +629,7 @@ proc useSeqOrStrOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
      if op == nil:
        return # protect from recursion
      body.add newHookCall(c, op, x, y)
-  of attachedWasMoved: body.add genBuiltin(c, mWasMoved, "wasMoved", x)
+  of attachedWasMoved: body.add genBuiltin(c, mWasMoved, "`=wasMoved`", x)
  of attachedDup:
    # XXX: replace these with assertions.
    let op = getAttachedOp(c.g, t, c.kind)
@@ -694,11 +651,11 @@ proc fillStrOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
    body.add genBuiltin(c, mDestroy, "destroy", x)
  of attachedTrace:
    discard "strings are atomic and have no inner elements that are to trace"
-  of attachedWasMoved: body.add genBuiltin(c, mWasMoved, "wasMoved", x)
+  of attachedWasMoved: body.add genBuiltin(c, mWasMoved, "`=wasMoved`", x)

 proc cyclicType*(g: ModuleGraph, t: PType): bool =
  case t.kind
-  of tyRef: result = types.canFormAcycle(g, t.elementType)
+  of tyRef: result = types.canFormAcycle(g, t.lastSon)
  of tyProc: result = t.callConv == ccClosure
  else: result = false

@@ -723,7 +680,7 @@ proc atomicRefOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =

  ]#
  var actions = newNodeI(nkStmtList, c.info)
-  let elemType = t.elementType
+  let elemType = t.lastSon

  createTypeBoundOps(c.g, c.c, elemType, c.info, c.idgen)
  let isCyclic = c.g.config.selectedGC == gcOrc and types.canFormAcycle(c.g, elemType)
@@ -793,7 +750,7 @@ proc atomicRefOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
        # If the ref is polymorphic we have to account for this
        body.add callCodegenProc(c.g, "nimTraceRefDyn", c.info, genAddrOf(x, c.idgen), y)
      #echo "can follow ", elemType, " static ", isFinal(elemType)
-  of attachedWasMoved: body.add genBuiltin(c, mWasMoved, "wasMoved", x)
+  of attachedWasMoved: body.add genBuiltin(c, mWasMoved, "`=wasMoved`", x)
  of attachedDup:
    if isCyclic:
      body.add newAsgnStmt(x, y)
@@ -860,7 +817,7 @@ proc atomicClosureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
  of attachedDeepCopy: assert(false, "cannot happen")
  of attachedTrace:
    body.add callCodegenProc(c.g, "nimTraceRefDyn", c.info, genAddrOf(xenv, c.idgen), y)
-  of attachedWasMoved: body.add genBuiltin(c, mWasMoved, "wasMoved", x)
+  of attachedWasMoved: body.add genBuiltin(c, mWasMoved, "`=wasMoved`", x)

 proc weakrefOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
  case c.kind
@@ -888,12 +845,12 @@ proc weakrefOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
      body.sons.insert(des, 0)
  of attachedDeepCopy: assert(false, "cannot happen")
  of attachedTrace: discard
-  of attachedWasMoved: body.add genBuiltin(c, mWasMoved, "wasMoved", x)
+  of attachedWasMoved: body.add genBuiltin(c, mWasMoved, "`=wasMoved`", x)

 proc ownedRefOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
  var actions = newNodeI(nkStmtList, c.info)

-  let elemType = t.skipModifier
+  let elemType = t.lastSon
  #fillBody(c, elemType, actions, genDeref(x), genDeref(y))
  #var disposeCall = genBuiltin(c, mDispose, "dispose", x)

@@ -916,7 +873,7 @@ proc ownedRefOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
    body.add genIf(c, x, actions)
  of attachedDeepCopy: assert(false, "cannot happen")
  of attachedTrace: discard
-  of attachedWasMoved: body.add genBuiltin(c, mWasMoved, "wasMoved", x)
+  of attachedWasMoved: body.add genBuiltin(c, mWasMoved, "`=wasMoved`", x)

 proc closureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
  if c.kind == attachedDeepCopy:
@@ -956,7 +913,7 @@ proc closureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
        body.sons.insert(des, 0)
    of attachedDeepCopy: assert(false, "cannot happen")
    of attachedTrace: discard
-    of attachedWasMoved: body.add genBuiltin(c, mWasMoved, "wasMoved", x)
+    of attachedWasMoved: body.add genBuiltin(c, mWasMoved, "`=wasMoved`", x)

 proc ownedClosureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
  let xx = genBuiltin(c, mAccessEnv, "accessEnv", x)
@@ -974,7 +931,7 @@ proc ownedClosureOp(c: var TLiftCtx; t: PType; body, x, y: PNode) =
    body.add genIf(c, xx, actions)
  of attachedDeepCopy: assert(false, "cannot happen")
  of attachedTrace: discard
-  of attachedWasMoved: body.add genBuiltin(c, mWasMoved, "wasMoved", x)
+  of attachedWasMoved: body.add genBuiltin(c, mWasMoved, "`=wasMoved`", x)

 proc fillBody(c: var TLiftCtx; t: PType; body, x, y: PNode) =
  case t.kind
@@ -1024,20 +981,14 @@ proc fillBody(c: var TLiftCtx; t: PType; body, x, y: PNode) =
      # 'selectedGC' here to determine if we have the new runtime.
      discard considerUserDefinedOp(c, t, body, x, y)
    elif tfHasAsgn in t.flags:
-      # seqs with elements using custom hooks in refc
      if c.kind in {attachedAsgn, attachedSink, attachedDeepCopy}:
        body.add newSeqCall(c, x, y)
-      if c.kind == attachedWasMoved:
-        body.add genBuiltin(c, mWasMoved, "wasMoved", x)
-      else:
-        forallElements(c, t, body, x, y)
+      forallElements(c, t, body, x, y)
    else:
      defaultOp(c, t, body, x, y)
  of tyString:
    if useNoGc(c, t):
      useSeqOrStrOp(c, t, body, x, y)
-    elif c.g.config.selectedGC == gcRefc:
-      defaultOp(c, t, body, x, y)
    elif tfHasAsgn in t.flags:
      discard considerUserDefinedOp(c, t, body, x, y)
    else:
@@ -1049,11 +1000,9 @@ proc fillBody(c: var TLiftCtx; t: PType; body, x, y: PNode) =
        of {attachedAsgn, attachedSink, attachedDup}:
          body.add newAsgnStmt(x, y)
        of attachedWasMoved:
-          body.add genBuiltin(c, mWasMoved, "wasMoved", x)
+          body.add genBuiltin(c, mWasMoved, "`=wasMoved`", x)
        else:
          fillBodyObjT(c, t, body, x, y)
-      elif tfUnion in t.flags: # bug #25236
-        defaultOp(c, t, body, x, y)
      else:
        if c.kind == attachedDup:
          var op2 = getAttachedOp(c.g, t, attachedAsgn)
@@ -1067,7 +1016,7 @@ 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.elementType, body, x, y)
+      fillBody(c, t[0], body, x, y)
  of tyTuple:
    fillBodyTup(c, t, body, x, y)
  of tyVarargs, tyOpenArray:
@@ -1076,7 +1025,7 @@ proc fillBody(c: var TLiftCtx; t: PType; body, x, y: PNode) =
    else:
      discard "cannot copy openArray"

-  of tyFromExpr, tyError, tyBuiltInTypeClass, tyUserTypeClass,
+  of tyFromExpr, tyProxy, tyBuiltInTypeClass, tyUserTypeClass,
     tyUserTypeClassInst, tyCompositeTypeClass, tyAnd, tyOr, tyNot, tyAnything,
     tyGenericParam, tyGenericBody, tyNil, tyUntyped, tyTyped,
     tyTypeDesc, tyGenericInvocation, tyForward, tyStatic:
@@ -1084,14 +1033,14 @@ proc fillBody(c: var TLiftCtx; t: PType; body, x, y: PNode) =
    discard
  of tyOrdinal, tyRange, tyInferred,
     tyGenericInst, tyAlias, tySink:
-    fillBody(c, skipModifier(t), body, x, y)
+    fillBody(c, lastSon(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.elementType
+  let baseType = typ[0]
  if getAttachedOp(g, baseType, kind) == nil:
    discard produceSym(g, c, baseType, kind, info, idgen)
  result = getAttachedOp(g, baseType, kind)
@@ -1107,7 +1056,7 @@ proc symDupPrototype(g: ModuleGraph; typ: PType; owner: PSym; kind: TTypeAttache
  res.typ = typ
  src.typ = typ

-  result.typ = newType(tyProc, idgen, owner)
+  result.typ = newType(tyProc, nextTypeId idgen, owner)
  result.typ.n = newNodeI(nkFormalParams, info)
  rawAddSon(result.typ, res.typ)
  result.typ.n.add newNodeI(nkEffectList, info)
@@ -1128,10 +1077,11 @@ proc symDupPrototype(g: ModuleGraph; typ: PType; owner: PSym; kind: TTypeAttache
  n[bodyPos] = newNodeI(nkStmtList, info)
  n[resultPos] = newSymNode(res)
  result.ast = n
-  incl result.flagsImpl, {sfFromGeneric, sfGeneratedOp}
+  incl result.flags, sfFromGeneric
+  incl result.flags, sfGeneratedOp

 proc symPrototype(g: ModuleGraph; typ: PType; owner: PSym; kind: TTypeAttachedOp;
-              info: TLineInfo; idgen: IdGenerator; isDiscriminant = false): PSym =
+              info: TLineInfo; idgen: IdGenerator): PSym =
  if kind == attachedDup:
    return symDupPrototype(g, typ, owner, kind, info, idgen)

@@ -1141,8 +1091,7 @@ 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 g.config.selectedGC in {gcArc, gcOrc, gcAtomicArc} and
-     ((g.config.isDefined("nimPreviewNonVarDestructor") and not isDiscriminant) or (typ.kind in {tyRef, tyString, tySequence})):
+  if kind == attachedDestructor and typ.kind in {tyRef, tyString, tySequence} and g.config.selectedGC in {gcArc, gcOrc, gcAtomicArc}:
    dest.typ = typ
  else:
    dest.typ = makeVarType(typ.owner, typ, idgen)
@@ -1152,7 +1101,7 @@ proc symPrototype(g: ModuleGraph; typ: PType; owner: PSym; kind: TTypeAttachedOp
  else:
    src.typ = typ

-  result.typ = newProcType(info, idgen, owner)
+  result.typ = newProcType(info, nextTypeId(idgen), owner)
  result.typ.addParam dest
  if kind notin {attachedDestructor, attachedWasMoved}:
    result.typ.addParam src
@@ -1170,11 +1119,11 @@ proc symPrototype(g: ModuleGraph; typ: PType; owner: PSym; kind: TTypeAttachedOp
  n[paramsPos] = result.typ.n
  n[bodyPos] = newNodeI(nkStmtList, info)
  result.ast = n
-  incl result.flagsImpl, sfFromGeneric
-  incl result.flagsImpl, sfGeneratedOp
+  incl result.flags, sfFromGeneric
+  incl result.flags, sfGeneratedOp
  if kind == attachedWasMoved:
-    incl result.flagsImpl, sfNoSideEffect
-    incl result.typ, tfNoSideEffect
+    incl result.flags, sfNoSideEffect
+    incl result.typ.flags, tfNoSideEffect

 proc genTypeFieldCopy(c: var TLiftCtx; t: PType; body, x, y: PNode) =
  let xx = genBuiltin(c, mAccessTypeField, "accessTypeField", x)
@@ -1196,7 +1145,7 @@ 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.firstParamType.kind == tyVar: newDeref(newSymNode(dest)) else: newSymNode(dest)
+  let d = if result.typ[1].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)
@@ -1207,17 +1156,14 @@ proc produceSym(g: ModuleGraph; c: PContext; typ: PType; kind: TTypeAttachedOp;

  if kind == attachedSink and destructorOverridden(g, typ):
    ## compiler can use a combination of `=destroy` and memCopy for sink op
-    ensureMutable dest
-    dest.flagsImpl.incl sfCursor
+    dest.flags.incl sfCursor
    let op = getAttachedOp(g, typ, attachedDestructor)
-    result.ast[bodyPos].add newOpCall(a, op, if op.typ.firstParamType.kind == tyVar: d[0] else: d)
+    result.ast[bodyPos].add newOpCall(a, op, if op.typ[1].kind == tyVar: d[0] else: d)
    result.ast[bodyPos].add newAsgnStmt(d, src)
  else:
    var tk: TTypeKind
-    var skipped: PType = nil
    if g.config.selectedGC in {gcArc, gcOrc, gcHooks, gcAtomicArc}:
-      skipped = skipTypes(typ, {tyOrdinal, tyRange, tyInferred, tyGenericInst, tyStatic, tyAlias, tySink})
-      tk = skipped.kind
+      tk = skipTypes(typ, {tyOrdinal, tyRange, tyInferred, tyGenericInst, tyStatic, tyAlias, tySink}).kind
    else:
      tk = tyNone # no special casing for strings and seqs
    case tk
@@ -1227,28 +1173,18 @@ proc produceSym(g: ModuleGraph; c: PContext; typ: PType; kind: TTypeAttachedOp;
      fillStrOp(a, typ, result.ast[bodyPos], d, src)
    else:
      fillBody(a, typ, result.ast[bodyPos], d, src)
-      if tk == tyObject and a.kind in {attachedAsgn, attachedSink, attachedDeepCopy, attachedDup} and not isObjLackingTypeField(skipped):
+      if tk == tyObject and a.kind in {attachedAsgn, attachedSink, attachedDeepCopy, attachedDup} and not lacksMTypeField(typ):
        # bug #19205: Do not forget to also copy the hidden type field:
        genTypeFieldCopy(a, typ, result.ast[bodyPos], d, src)

-  if not a.canRaise:
-    ensureMutable result
-    incl result.flagsImpl, sfNeverRaises
-    result.ast[pragmasPos] = newNodeI(nkPragma, info)
-    result.ast[pragmasPos].add newTree(nkExprColonExpr,
-        newIdentNode(g.cache.getIdent("raises"),  info), newNodeI(nkBracket, info))
-
-  if kind == attachedDestructor:
-    ensureMutable result
-    incl result.optionsImpl, optQuirky
+  if not a.canRaise: incl result.flags, sfNeverRaises
  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)
-  # 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)
+  result = symPrototype(g, field.typ, typ.owner, attachedDestructor, info, idgen)
  var a = TLiftCtx(info: info, g: g, kind: attachedDestructor, asgnForType: typ, idgen: idgen,
                   fn: result)
  a.asgnForType = typ
@@ -1265,9 +1201,7 @@ proc produceDestructorForDiscriminator*(g: ModuleGraph; typ: PType; field: PSym,
  result.ast[bodyPos].add v
  let placeHolder = newNodeIT(nkSym, info, getSysType(g, info, tyPointer))
  fillBody(a, typ, result.ast[bodyPos], d, placeHolder)
-  if not a.canRaise:
-    ensureMutable result
-    incl result.flagsImpl, sfNeverRaises
+  if not a.canRaise: incl result.flags, sfNeverRaises


 template liftTypeBoundOps*(c: PContext; typ: PType; info: TLineInfo) =
@@ -1302,7 +1236,7 @@ proc inst(g: ModuleGraph; c: PContext; t: PType; kind: TTypeAttachedOp; idgen: I
    else:
      localError(g.config, info, "unresolved generic parameter")

-proc isTrivial*(s: PSym): bool {.inline.} =
+proc isTrival(s: PSym): bool {.inline.} =
  s == nil or (s.ast != nil and s.ast[bodyPos].len == 0)

 proc createTypeBoundOps(g: ModuleGraph; c: PContext; orig: PType; info: TLineInfo;
@@ -1311,13 +1245,7 @@ proc createTypeBoundOps(g: ModuleGraph; c: PContext; orig: PType; info: TLineInf
  ## to ensure we lift assignment, destructors and moves properly.
  ## The later 'injectdestructors' pass depends on it.
  if orig == nil or {tfCheckedForDestructor, tfHasMeta} * orig.flags != {}: return
-  # IC: review this solution again later
-  incl orig.flagsImpl, tfCheckedForDestructor
-  # for user defined generic destructors:
-  let origRoot = genericRoot(orig)
-  if origRoot != nil:
-    # IC: review this solution again later
-    incl origRoot.flagsImpl, tfGenericHasDestructor
+  incl orig.flags, tfCheckedForDestructor

  let skipped = orig.skipTypes({tyGenericInst, tyAlias, tySink})
  if isEmptyContainer(skipped) or skipped.kind == tyStatic: return
@@ -1343,7 +1271,7 @@ 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 = default(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]:
@@ -1359,9 +1287,8 @@ proc createTypeBoundOps(g: ModuleGraph; c: PContext; orig: PType; info: TLineInf
    if canon != orig:
      setAttachedOp(g, idgen.module, orig, k, getAttachedOp(g, canon, k))

-  if not isTrivial(getAttachedOp(g, orig, attachedDestructor)):
-    #or not isTrivial(orig.assignment) or
-    # not isTrivial(orig.sink):
-    # IC: review this solution again later
-    orig.flagsImpl.incl tfHasAsgn
+  if not isTrival(getAttachedOp(g, orig, attachedDestructor)):
+    #or not isTrival(orig.assignment) or
+    # not isTrival(orig.sink):
+    orig.flags.incl tfHasAsgn
    # ^ XXX Breaks IC!
--- a/compiler/liftlocals.nim
+++ b/compiler/liftlocals.nim
@@ -10,11 +10,9 @@
 ## This module implements the '.liftLocals' pragma.

 import
-  options, ast, msgs,
+  strutils, options, ast, msgs,
  idents, renderer, types, lowerings, lineinfos

-import std/strutils
-
 from pragmas import getPragmaVal
 from wordrecg import wLiftLocals

--- a/compiler/lineinfos.nim
+++ b/compiler/lineinfos.nim
@@ -10,8 +10,7 @@
 ## This module contains the `TMsgKind` enum as well as the
 ## `TLineInfo` object.

-import ropes, pathutils
-import std/[hashes, tables]
+import ropes, tables, pathutils, hashes

 const
  explanationsBaseUrl* = "https://nim-lang.github.io/Nim"
@@ -92,11 +91,7 @@ type
    warnStmtListLambda = "StmtListLambda",
    warnBareExcept = "BareExcept",
    warnImplicitDefaultValue = "ImplicitDefaultValue",
-    warnIgnoredSymbolInjection = "IgnoredSymbolInjection",
-    warnStdPrefix = "StdPrefix"
-    warnUnknownNotes = "UnknownNotes"
    warnUser = "User",
-    warnGlobalVarConstructorTemporary = "GlobalVarConstructorTemporary",
    # hints
    hintSuccess = "Success", hintSuccessX = "SuccessX",
    hintCC = "CC",
@@ -109,8 +104,8 @@ 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",
-    hintUnknownRaises = "UnknownRaises",
    hintMsgOrigin = "MsgOrigin", # since 1.3.5
    hintDeclaredLoc = "DeclaredLoc", # since 1.5.1

@@ -190,7 +185,7 @@ const
    warnAnyEnumConv: "$1",
    warnHoleEnumConv: "$1",
    warnCstringConv: "$1",
-    warnPtrToCstringConv: "unsafe conversion to 'cstring' from '$1'; Use a `cast` operation like `cast[cstring](x)`; this will become a compile time error in the future",
+    warnPtrToCstringConv: "unsafe conversion to 'cstring' from '$1'; this will become a compile time error in the future",
    warnEffect: "$1",
    warnCastSizes: "$1", # deadcode
    warnAboveMaxSizeSet: "$1",
@@ -199,11 +194,7 @@ const
    warnStmtListLambda: "statement list expression assumed to be anonymous proc; this is deprecated, use `do (): ...` or `proc () = ...` instead",
    warnBareExcept: "$1",
    warnImplicitDefaultValue: "$1",
-    warnIgnoredSymbolInjection: "$1",
-    warnStdPrefix: "$1 needs the 'std' prefix",
-    warnUnknownNotes: "$1",
    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",
@@ -234,12 +225,12 @@ const
    hintGCStats: "$1",
    hintGlobalVar: "global variable declared here",
    hintExpandMacro: "expanded macro: $1",
+    hintAmbiguousEnum: "$1",
    hintUser: "$1",
    hintUserRaw: "$1",
    hintExtendedContext: "$1",
-    hintUnknownRaises: "$1 is a forward declaration without explicit .raises, assuming it can raise anything",
    hintMsgOrigin: "$1",
-    hintDeclaredLoc: "$1"
+    hintDeclaredLoc: "$1",
  ]

 const
@@ -258,7 +249,7 @@ type

 proc computeNotesVerbosity(): array[0..3, TNoteKinds] =
  result = default(array[0..3, TNoteKinds])
-  result[3] = {low(TNoteKind)..high(TNoteKind)} - {warnObservableStores, warnResultUsed, warnAnyEnumConv, warnBareExcept, warnStdPrefix}
+  result[3] = {low(TNoteKind)..high(TNoteKind)} - {warnObservableStores, warnResultUsed, warnAnyEnumConv, warnBareExcept}
  result[2] = result[3] - {hintStackTrace, hintExtendedContext, hintDeclaredLoc, hintProcessingStmt}
  result[1] = result[2] - {warnProveField, warnProveIndex,
    warnGcUnsafe, hintPath, hintDependency, hintCodeBegin, hintCodeEnd,
@@ -270,13 +261,8 @@ 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
-  FileInfoKind* = enum
-    fikSource,      ## A real source file path
-    fikNifModule    ## A NIF module suffix (not a real path)
-
  TFileInfo* = object
    fullPath*: AbsoluteFile    # This is a canonical full filesystem path
    projPath*: RelativeFile    # This is relative to the project's root
@@ -295,7 +281,6 @@ type
                               # for 'nimsuggest'
    hash*: string              # the checksum of the file
    dirty*: bool               # for 'nimpretty' like tooling
-    kind*: FileInfoKind        # distinguishes real files from NIF suffixes
    when defined(nimpretty):
      fullContent*: string
  FileIndex* = distinct int32
--- a/compiler/linter.nim
+++ b/compiler/linter.nim
@@ -12,7 +12,7 @@
 import std/strutils
 from std/sugar import dup

-import options, ast, msgs, idents, lineinfos, wordrecg, astmsgs, semdata, packages, modulegraphs
+import options, ast, msgs, idents, lineinfos, wordrecg, astmsgs, semdata, packages
 export packages

 const
@@ -97,7 +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.belongsToProjectPackageMaybeNil(getModule(ctx.graph, info.fileIndex)) and # ignore foreign packages
+     ctx.config.belongsToProjectPackage(sym) 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
@@ -138,7 +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.belongsToProjectPackageMaybeNil(getModule(ctx.graph, info.fileIndex)) and # ignore foreign packages
+     ctx.config.belongsToProjectPackage(sym) 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
@@ -154,5 +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
-     ctx.config.belongsToProjectPackageMaybeNil(getModule(ctx.graph, info.fileIndex)): # ignore foreign packages
+     (sym != nil and ctx.config.belongsToProjectPackage(sym)): # ignore foreign packages
    checkPragmaUseImpl(ctx.config, info, w, pragmaName)
--- a/compiler/llstream.nim
+++ b/compiler/llstream.nim
@@ -11,7 +11,7 @@

 import
  pathutils
-import std/strutils
+
 when defined(nimPreviewSlimSystem):
  import std/syncio

@@ -19,7 +19,7 @@ when defined(nimPreviewSlimSystem):
 const hasRstdin = (defined(nimUseLinenoise) or defined(useLinenoise) or defined(useGnuReadline)) and
  not defined(windows)

-when hasRstdin: import std/rdstdin
+when hasRstdin: import rdstdin

 type
  TLLRepl* = proc (s: PLLStream, buf: pointer, bufLen: int): int
@@ -68,7 +68,6 @@ 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")
@@ -86,47 +85,6 @@ const
  LineContinuationOprs = {'+', '-', '*', '/', '\\', '<', '>', '!', '?', '^',
                          '|', '%', '&', '$', '@', '~', ','}
  AdditionalLineContinuationOprs = {'#', ':', '='}
-  LineContinuationTokens = [
-    "let", "var", "const", "type",  # section
-    "object", "tuple",
-    # from ./layouter.oprSet
-    "div", "mod", "shl", "shr", "in", "notin", "is",
-    "isnot", "not", "of", "as", "from", "..", "and", "or", "xor", 
-  ]  # must be all `nimIdentNormalized`-ed
-
-proc eqIdent(a, bNormalized: string): bool =
-  a.nimIdentNormalize == bNormalized
-
-proc endsWithIdent(s, subs: string): bool =
-  let le = subs.len
-  if le > s.len: return false
-  s[^le .. ^1].eqIdent subs
-
-proc continuesWithIdent(s, subs: string, start: int): bool =
-  s.substr(start, start+subs.high).eqIdent subs
-
-proc endsWithIdent(s, subs: string, endIdx: var int): bool =
-  endIdx.dec subs.len
-  result = s.continuesWithIdent(subs, endIdx+1)
-
-proc containsObjectOf(x: string): bool =
-  const sep = ' '
-  var idx = x.rfind(sep)
-  if idx == -1: return
-  template eatWord(word) =  
-    while x[idx] == sep: idx.dec
-    result = x.endsWithIdent(word, idx)
-    if not result: return
-  eatWord "of"
-  eatWord "object"
-  result = true
-
-proc endsWithLineContinuationToken(x: string): bool =
-  result = false
-  for tok in LineContinuationTokens:
-    if x.endsWithIdent(tok):
-      return true
-  result = x.containsObjectOf

 proc endsWithOpr*(x: string): bool =
  result = x.endsWith(LineContinuationOprs)
@@ -134,9 +92,7 @@ proc endsWithOpr*(x: string): bool =
 proc continueLine(line: string, inTripleString: bool): bool {.inline.} =
  result = inTripleString or line.len > 0 and (
        line[0] == ' ' or
-        line.endsWith(LineContinuationOprs+AdditionalLineContinuationOprs) or
-        line.endsWithLineContinuationToken()
-      )
+        line.endsWith(LineContinuationOprs+AdditionalLineContinuationOprs))

 proc countTriples(s: string): int =
  result = 0
@@ -152,10 +108,7 @@ proc llReadFromStdin(s: PLLStream, buf: pointer, bufLen: int): int =
  s.rd = 0
  var line = newStringOfCap(120)
  var triples = 0
-  while true:
-    if not readLineFromStdin(if s.s.len == 0: ">>> " else: "... ", line):
-      # now readLineFromStdin meets EOF (ctrl-D/Z) or ctrl-C
-      quit()
+  while readLineFromStdin(if s.s.len == 0: ">>> " else: "... ", line):
    s.s.add(line)
    s.s.add("\n")
    inc triples, countTriples(line)
--- a/compiler/lookups.nim
+++ b/compiler/lookups.nim
@@ -14,10 +14,8 @@ when defined(nimPreviewSlimSystem):
  import std/assertions

 import
-  ast, astalgo, idents, semdata, types, msgs, options,
-  renderer, lineinfos, modulegraphs, astmsgs, wordrecg
-
-import std/[intsets, sets]
+  intsets, ast, astalgo, idents, semdata, types, msgs, options,
+  renderer, lineinfos, modulegraphs, astmsgs, sets, wordrecg

 proc ensureNoMissingOrUnusedSymbols(c: PContext; scope: PScope)

@@ -50,7 +48,7 @@ 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, nkOpenSym:
+        of nkSymChoices:
          if x[0].kind == nkSym:
            id.add(x[0].sym.name.s)
          else:
@@ -58,7 +56,7 @@ proc considerQuotedIdent*(c: PContext; n: PNode, origin: PNode = nil): PIdent =
        of nkLiterals - nkFloatLiterals: id.add(x.renderTree)
        else: handleError(n, origin)
      result = getIdent(c.cache, id)
-  of nkOpenSymChoice, nkClosedSymChoice, nkOpenSym:
+  of nkOpenSymChoice, nkClosedSymChoice:
    if n[0].kind == nkSym:
      result = n[0].sym.name
    else:
@@ -75,13 +73,10 @@ proc addUniqueSym*(scope: PScope, s: PSym): PSym =
 proc openScope*(c: PContext): PScope {.discardable.} =
  result = PScope(parent: c.currentScope,
                  symbols: initStrTable(),
-                  depthLevel: c.scopeDepth + 1,
-                  optionStackLen: c.optionStack.len)
+                  depthLevel: c.scopeDepth + 1)
  c.currentScope = result

 proc rawCloseScope*(c: PContext) =
-  if c.currentScope.optionStackLen >= 1:
-    c.optionStack.setLen(c.currentScope.optionStackLen)
  c.currentScope = c.currentScope.parent

 proc closeScope*(c: PContext) =
@@ -140,7 +135,7 @@ 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 = default(ModuleIter)
+  var ti: ModuleIter
  var candidate = initIdentIter(ti, marked, im, name, g)
  while candidate != nil:
    yield candidate
@@ -153,7 +148,7 @@ iterator importedItems*(c: PContext; name: PIdent): PSym =
      yield s

 proc allPureEnumFields(c: PContext; name: PIdent): seq[PSym] =
-  var ti: TIdentIter = default(TIdentIter)
+  var ti: TIdentIter
  result = @[]
  var res = initIdentIter(ti, c.pureEnumFields, name)
  while res != nil:
@@ -222,33 +217,28 @@ proc debugScopes*(c: PContext; limit=0, max = int.high) {.deprecated.} =
    if i == limit: return
    inc i

-proc searchImportsAll*(c: PContext, s: PIdent, filter: TSymKinds, holding: var seq[PSym]) =
-  var marked = initIntSet()
-  for im in c.imports.mitems:
-    for s in symbols(im, marked, s, c.graph):
-      if s.kind in filter:
-        holding.add s
-
-proc searchScopes*(c: PContext, s: PIdent, filter: TSymKinds): seq[PSym] =
+proc searchInScopesAllCandidatesFilterBy*(c: PContext, s: PIdent, filter: TSymKinds): seq[PSym] =
  result = @[]
  for scope in allScopes(c.currentScope):
-    var ti: TIdentIter = default(TIdentIter)
+    var ti: TIdentIter
    var candidate = initIdentIter(ti, scope.symbols, s)
    while candidate != nil:
      if candidate.kind in filter:
        result.add candidate
      candidate = nextIdentIter(ti, scope.symbols)

-proc searchScopesAll*(c: PContext, s: PIdent, filter: TSymKinds): seq[PSym] =
-  result = searchScopes(c,s,filter)
  if result.len == 0:
-    searchImportsAll(c, s, filter, result)
+    var marked = initIntSet()
+    for im in c.imports.mitems:
+      for s in symbols(im, marked, s, c.graph):
+        if s.kind in filter:
+          result.add s

-proc selectFromScopesElseAll*(c: PContext, s: PIdent, filter: TSymKinds): seq[PSym] =
+proc searchInScopesFilterBy*(c: PContext, s: PIdent, filter: TSymKinds): seq[PSym] =
  result = @[]
  block outer:
    for scope in allScopes(c.currentScope):
-      var ti: TIdentIter = default(TIdentIter)
+      var ti: TIdentIter
      var candidate = initIdentIter(ti, scope.symbols, s)
      while candidate != nil:
        if candidate.kind in filter:
@@ -258,25 +248,17 @@ proc selectFromScopesElseAll*(c: PContext, s: PIdent, filter: TSymKinds): seq[PS
        candidate = nextIdentIter(ti, scope.symbols)

  if result.len == 0:
-    searchImportsAll(c, s, filter, result)
-
-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
+    var marked = initIntSet()
+    for im in c.imports.mitems:
+      for s in symbols(im, marked, s, c.graph):
+        if s.kind in filter:
+          result.add s

 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 = default(TIdentIter)
+      var ti: TIdentIter
      var candidate = initIdentIter(ti, scope.symbols, s)
      var scopeHasCandidate = false
      while candidate != nil:
@@ -307,16 +289,8 @@ 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, 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.flagsImpl, 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 =
+  ## creates an error symbol to avoid cascading errors (for IDE support)
  var m = n
  # ensure that 'considerQuotedIdent' can't fail:
  if m.kind == nkDotExpr: m = m[1]
@@ -324,7 +298,12 @@ proc errorSym*(c: PContext, n: PNode): PSym =
      considerQuotedIdent(c, m)
    else:
      getIdent(c.cache, "err:" & renderTree(m))
-  result = errorSym(c, ident, n.info)
+  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)

 type
  TOverloadIterMode* = enum
@@ -351,7 +330,7 @@ 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 = default(TTabIter)
+  var it: TTabIter
  var s = initTabIter(it, scope.symbols)
  var missingImpls = 0
  var unusedSyms: seq[tuple[sym: PSym, key: string]] = @[]
@@ -388,7 +367,7 @@ proc addDeclAt*(c: PContext; scope: PScope, sym: PSym, info: TLineInfo) =
  if sym.name.id == ord(wUnderscore): return
  let conflict = scope.addUniqueSym(sym)
  if conflict != nil:
-    if sym.kind == skModule and conflict.kind == skModule and not c.config.isDefined("nimPreviewDuplicateModuleError"):
+    if sym.kind == skModule and conflict.kind == skModule:
      # e.g.: import foo; import foo
      # xxx we could refine this by issuing a different hint for the case
      # where a duplicate import happens inside an include.
@@ -485,7 +464,7 @@ proc mergeShadowScope*(c: PContext) =
      c.addInterfaceDecl(sym)


-import std/[editdistance, heapqueue]
+import std/editdistance, heapqueue

 type SpellCandidate = object
  dist: int
@@ -506,7 +485,7 @@ proc mustFixSpelling(c: PContext): bool {.inline.} =
  result = c.config.spellSuggestMax != 0 and c.compilesContextId == 0
    # don't slowdown inside compiles()

-proc fixSpelling(c: PContext, ident: PIdent, result: var string) =
+proc fixSpelling(c: PContext, n: PNode, ident: PIdent, result: var string) =
  ## when we cannot find the identifier, suggest nearby spellings
  var list = initHeapQueue[SpellCandidate]()
  let name0 = ident.s.nimIdentNormalize
@@ -562,47 +541,33 @@ 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 = false
+  var amb: bool
  discard errorUseQualifier(c, info, s, amb)

-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 & "'"
+proc errorUseQualifier(c: PContext; info: TLineInfo; candidates: seq[PSym]; prefix = "use one of") =
+  var err = "ambiguous identifier: '" & candidates[0].name.s & "'"
  var i = 0
  for candidate in candidates:
-    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)
+    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)
    inc i
+  localError(c.config, info, errGenerated, err)

-proc errorUseQualifier*(c: PContext; info: TLineInfo; candidates: seq[PSym]) =
-  localError(c.config, info, errGenerated, ambiguousIdentifierMsg(candidates))
-
-proc ambiguousIdentifierMsg*(choices: PNode, indent = 0): string =
+proc errorUseQualifier*(c: PContext; info:TLineInfo; choices: PNode) =
  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
-  result = ambiguousIdentifierMsg(candidates, prefix, indent)
-
-proc errorUseQualifier*(c: PContext; info:TLineInfo; choices: PNode) =
-  localError(c.config, info, errGenerated, ambiguousIdentifierMsg(choices))
+  errorUseQualifier(c, info, candidates, prefix)

 proc errorUndeclaredIdentifier*(c: PContext; info: TLineInfo; name: string, extra = "") =
  var err: string
  if name == "_":
    err = "the special identifier '_' is ignored in declarations and cannot be used"
  else:
-    err = "undeclared identifier: '" & name & "'"
-    if "`gensym" in name:
-      err.add "; if declared in a template, this identifier may be inconsistently marked inject or gensym"
-    if extra.len != 0:
-      err.add extra
+    err = "undeclared identifier: '" & name & "'" & extra
    if c.recursiveDep.len > 0:
      err.add "\nThis might be caused by a recursive module dependency:\n"
      err.add c.recursiveDep
@@ -610,11 +575,11 @@ proc errorUndeclaredIdentifier*(c: PContext; info: TLineInfo; name: string, extr
      c.recursiveDep = ""
  localError(c.config, info, errGenerated, err)

-proc errorUndeclaredIdentifierHint*(c: PContext; ident: PIdent; info: TLineInfo): PSym =
+proc errorUndeclaredIdentifierHint*(c: PContext; n: PNode, ident: PIdent): PSym =
  var extra = ""
-  if c.mustFixSpelling: fixSpelling(c, ident, extra)
-  errorUndeclaredIdentifier(c, info, ident.s, extra)
-  result = errorSym(c, ident, info)
+  if c.mustFixSpelling: fixSpelling(c, n, ident, extra)
+  errorUndeclaredIdentifier(c, n.info, ident.s, extra)
+  result = errorSym(c, n)

 proc lookUp*(c: PContext, n: PNode): PSym =
  # Looks up a symbol. Generates an error in case of nil.
@@ -622,13 +587,13 @@ 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.ident, n.info)
+    if result == nil: result = errorUndeclaredIdentifierHint(c, n, n.ident)
  of nkSym:
    result = n.sym
  of nkAccQuoted:
    var ident = considerQuotedIdent(c, n)
    result = searchInScopes(c, ident, amb)
-    if result == nil: result = errorUndeclaredIdentifierHint(c, ident, n.info)
+    if result == nil: result = errorUndeclaredIdentifierHint(c, n, ident)
  else:
    internalError(c.config, n.info, "lookUp")
    return nil
@@ -642,30 +607,16 @@ 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 = selectFromScopesElseAll(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 = lookUpCandidates(c, ident, allExceptModule)
+      let candidates = searchInScopesFilterBy(c, ident, allExceptModule)
      if candidates.len > 0:
        result = candidates[0]
        amb = candidates.len > 1
@@ -673,47 +624,46 @@ proc qualifiedLookUp*(c: PContext, n: PNode, flags: set[TLookupFlag]): PSym =
          errorUseQualifier(c, n.info, candidates)
      else:
        result = nil
+    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)
+
    if result == nil and checkUndeclared in flags:
-      result = errorUndeclaredIdentifierHint(c, ident, n.info)
+      result = errorUndeclaredIdentifierHint(c, n, ident)
    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 == nkAccQuoted:
+      if n[1].kind == nkIdent:
+        ident = n[1].ident
+      elif 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:
-          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
+          result = strTableGet(c.topLevelScope.symbols, ident)
        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 = someSymAmb(c.graph, m, ident, amb)
-            if amb: c.isAmbiguous = true
+            result = someSym(c.graph, m, ident)
        if result == nil and checkUndeclared in flags:
-          result = errorUndeclaredIdentifierHint(c, ident, n[1].info)
+          result = errorUndeclaredIdentifierHint(c, n[1], ident)
      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, result.name, n[1].info)
+          result = errorUndeclaredIdentifierHint(c, n[1], considerQuotedIdent(c, n[1]))
      elif checkUndeclared in flags and
           n[1].kind notin {nkOpenSymChoice, nkClosedSymChoice}:
        localError(c.config, n[1].info, "identifier expected, but got: " &
@@ -725,10 +675,6 @@ 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
--- a/compiler/lowerings.nim
+++ b/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.elementType)
+  result = newNodeIT(nkHiddenDeref, n.info, n.typ[0])
  result.add n

 proc newTupleAccess*(g: ModuleGraph; tup: PNode, i: int): PNode =
@@ -82,7 +82,7 @@ proc lowerTupleUnpacking*(g: ModuleGraph; n: PNode; idgen: IdGenerator; owner: P
    var temp = newSym(skTemp, getIdent(g.cache, genPrefix), idgen,
                  owner, value.info, g.config.options)
    temp.typ = skipTypes(value.typ, abstractInst)
-    incl(temp.flagsImpl, sfFromGeneric)
+    incl(temp.flags, sfFromGeneric)
    tempAsNode = newSymNode(temp)

  var v = newNodeI(nkVarSection, value.info)
@@ -103,7 +103,7 @@ proc evalOnce*(g: ModuleGraph; value: PNode; idgen: IdGenerator; owner: PSym): P
  var temp = newSym(skTemp, getIdent(g.cache, genPrefix), idgen,
                    owner, value.info, g.config.options)
  temp.typ = skipTypes(value.typ, abstractInst)
-  incl(temp.flagsImpl, sfFromGeneric)
+  incl(temp.flags, sfFromGeneric)

  var v = newNodeI(nkLetSection, value.info)
  let tempAsNode = newSymNode(temp)
@@ -127,8 +127,8 @@ proc lowerSwap*(g: ModuleGraph; n: PNode; idgen: IdGenerator; owner: PSym): PNod
  # note: cannot use 'skTemp' here cause we really need the copy for the VM :-(
  var temp = newSym(skVar, getIdent(g.cache, genPrefix), idgen, owner, n.info, owner.options)
  temp.typ = n[1].typ
-  incl(temp.flagsImpl, sfFromGeneric)
-  incl(temp.flagsImpl, sfGenSym)
+  incl(temp.flags, sfFromGeneric)
+  incl(temp.flags, sfGenSym)

  var v = newNodeI(nkVarSection, n.info)
  let tempAsNode = newSymNode(temp)
@@ -144,16 +144,16 @@ 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, idgen, owner)
+  result = newType(tyObject, nextTypeId(idgen), owner)
  if final:
    rawAddSon(result, nil)
-    incl result, tfFinal
+    incl result.flags, tfFinal
  else:
    rawAddSon(result, getCompilerProc(g, "RootObj").typ)
  result.n = newNodeI(nkRecList, info)
  let s = newSym(skType, getIdent(g.cache, "Env_" & toFilename(g.config, info) & "_" & $owner.name.s),
                  idgen, owner, info, owner.options)
-  incl s.flagsImpl, sfAnon
+  incl s.flags, sfAnon
  s.typ = result
  result.sym = s

@@ -255,14 +255,14 @@ proc newDotExpr*(obj, b: PSym): PNode =
 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).elementType
+  deref.typ = a.typ.skipTypes(abstractInst)[0]
  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.baseClass
+    t = t[0]
    if t == nil: break
    t = t.skipTypes(skipPtrs)
  #if field == nil:
@@ -278,7 +278,7 @@ proc indirectAccess*(a: PNode, b: ItemId, info: TLineInfo): PNode =
 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).elementType
+  deref.typ = a.typ.skipTypes(abstractInst)[0]
  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.baseClass
+    t = t[0]
    if t == nil: break
    t = t.skipTypes(skipPtrs)
  #if field == nil:
@@ -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.baseClass
+    t = t[0]
    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, idgen, n.typ.owner)
+  result.typ = newType(typeKind, nextTypeId(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).elementType)
+                     n.typ.skipTypes(abstractInst)[0])
  result.add n

 proc callCodegenProc*(g: ModuleGraph; name: string;
@@ -344,7 +344,7 @@ proc callCodegenProc*(g: ModuleGraph; name: string;
    if optionalArgs != nil:
      for i in 1..<optionalArgs.len-2:
        result.add optionalArgs[i]
-    result.typ = sym.typ.returnType
+    result.typ = sym.typ[0]

 proc newIntLit*(g: ModuleGraph; info: TLineInfo; value: BiggestInt): PNode =
  result = nkIntLit.newIntNode(value)
--- a/compiler/magicsys.nim
+++ b/compiler/magicsys.nim
@@ -10,7 +10,7 @@
 # Built-in types and compilerprocs are registered here.

 import
-  ast, msgs, platform, idents,
+  ast, astalgo, msgs, platform, idents,
  modulegraphs, lineinfos

 export createMagic
@@ -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, g.idgen, g.systemModule)
+  result = newType(kind, nextTypeId(g.idgen), g.systemModule)
  result.size = size
  result.align = size.int16

@@ -27,7 +27,7 @@ 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, g.idgen, g.systemModule)
+    result.typ = newType(tyError, nextTypeId(g.idgen), g.systemModule)

 proc getSysMagic*(g: ModuleGraph; info: TLineInfo; name: string, m: TMagic): PSym =
  result = nil
@@ -35,12 +35,12 @@ proc getSysMagic*(g: ModuleGraph; info: TLineInfo; name: string, m: TMagic): PSy
  for r in systemModuleSyms(g, id):
    if r.magic == m:
      # prefer the tyInt variant:
-      if r.typ.returnType != nil and r.typ.returnType.kind == tyInt: return r
+      if r.typ[0] != nil and r.typ[0].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, g.idgen, g.systemModule)
+  result.typ = newType(tyError, nextTypeId(g.idgen), g.systemModule)

 proc sysTypeFromName*(g: ModuleGraph; info: TLineInfo; name: string): PType =
  result = getSysSym(g, info, name).typ
@@ -93,7 +93,7 @@ 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, id, t.owner)
+    result = copyType(t, nextTypeId(id), t.owner)
    result.n = nil
  else:
    result = t
@@ -103,13 +103,6 @@ proc addSonSkipIntLit*(father, son: PType; id: IdGenerator) =
  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)
@@ -157,13 +150,4 @@ proc getMagicEqSymForType*(g: ModuleGraph; t: PType; info: TLineInfo): PSym =
    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.skipTypes({tySink}), idgen)
--- a/compiler/main.nim
+++ b/compiler/main.nim
@@ -22,20 +22,19 @@ import
  modules,
  modulegraphs, lineinfos, pathutils, vmprofiler

+# ensure NIR compiles:
+import nir / nir

 when defined(nimPreviewSlimSystem):
  import std/[syncio, assertions]

-import ic / [cbackend, integrity, navigator, ic]
+import ic / [cbackend, integrity, navigator]
+from ic / ic import rodViewer

 import ../dist/checksums/src/checksums/sha1

 import pipelines

-when not defined(nimKochBootstrap):
-  import nifbackend
-  import deps
-
 when not defined(leanCompiler):
  import docgen

@@ -121,38 +120,6 @@ when not defined(leanCompiler):
    else: raiseAssert $ext
    compilePipelineProject(graph)

-proc commandCompileToNif(graph: ModuleGraph) =
-  let conf = graph.config
-  extccomp.initVars(conf)
-  if conf.symbolFiles == disabledSf:
-    if {optRun, optForceFullMake} * conf.globalOptions == {optRun} or isDefined(conf, "nimBetterRun"):
-      if not changeDetectedViaJsonBuildInstructions(conf, conf.jsonBuildInstructionsFile):
-        # nothing changed
-        graph.config.notes = graph.config.mainPackageNotes
-        return
-
-  if not extccomp.ccHasSaneOverflow(conf):
-    conf.symbols.defineSymbol("nimEmulateOverflowChecks")
-
-  setPipeLinePass(graph, NifgenPass)
-  compilePipelineProject(graph)
-
-proc commandNifC(graph: ModuleGraph) =
-  ## Generate C code from precompiled NIF files.
-  ## This is the new IC approach: compile modules to NIF first with `nim m`,
-  ## then generate C code from the entry.nif file with whole-program DCE.
-  when not defined(nimKochBootstrap):
-    let conf = graph.config
-    extccomp.initVars(conf)
-
-    if not extccomp.ccHasSaneOverflow(conf):
-      conf.symbols.defineSymbol("nimEmulateOverflowChecks")
-
-    # Use the NIF backend to generate C code
-    nifbackend.generateCode(graph, conf.projectMainIdx)
-  else:
-    rawMessage(graph.config, errGenerated, "NIF backend not available during bootstrap build")
-
 proc commandCompileToC(graph: ModuleGraph) =
  let conf = graph.config
  extccomp.initVars(conf)
@@ -186,7 +153,7 @@ proc commandCompileToC(graph: ModuleGraph) =
    extccomp.callCCompiler(conf)
    # for now we do not support writing out a .json file with the build instructions when HCR is on
    if not conf.hcrOn:
-      extccomp.writeJsonBuildInstructions(conf, graph.cachedFiles)
+      extccomp.writeJsonBuildInstructions(conf)
    if optGenScript in graph.config.globalOptions:
      writeDepsFile(graph)
    if optGenCDeps in graph.config.globalOptions:
@@ -220,7 +187,7 @@ proc commandInteractive(graph: ModuleGraph) =
    discard graph.compilePipelineModule(fileInfoIdx(graph.config, graph.config.projectFull), {})
  else:
    var m = graph.makeStdinModule()
-    incl(m, sfMainModule)
+    incl(m.flags, sfMainModule)
    var idgen = IdGenerator(module: m.itemId.module, symId: m.itemId.item, typeId: 0)
    let s = llStreamOpenStdIn(onPrompt = proc() = flushDot(graph.config))
    discard processPipelineModule(graph, m, idgen, s)
@@ -230,8 +197,9 @@ proc commandScan(cache: IdentCache, config: ConfigRef) =
  var stream = llStreamOpen(f, fmRead)
  if stream != nil:
    var
-      L: Lexer = default(Lexer)
+      L: Lexer
      tok: Token = default(Token)
+    initToken(tok)
    openLexer(L, f, stream, cache, config)
    while true:
      rawGetTok(L, tok)
@@ -293,7 +261,7 @@ proc mainCommand*(graph: ModuleGraph) =
      if conf.exc == excNone: conf.exc = excSetjmp
    of backendCpp:
      if conf.exc == excNone: conf.exc = excCpp
-    of backendObjc, backendNif: discard
+    of backendObjc: discard
    of backendJs:
      if conf.hcrOn:
        # XXX: At the moment, system.nim cannot be compiled in JS mode
@@ -311,7 +279,6 @@ proc mainCommand*(graph: ModuleGraph) =
    of backendCpp: commandCompileToC(graph)
    of backendObjc: commandCompileToC(graph)
    of backendJs: commandCompileToJS(graph)
-    of backendNif: commandCompileToNif(graph)
    of backendInvalid: raiseAssert "unreachable"

  template docLikeCmd(body) =
@@ -332,18 +299,14 @@ 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
-    if not ret.string.isAbsolute: # `AbsoluteDir` is not a real guarantee
-      rawMessage(conf, errCannotOpenFile, ret.string & "/")
+    doAssert ret.string.isAbsolute # `AbsoluteDir` is not a real guarantee
    if conf.cmd in cmdDocLike + {cmdRst2html, cmdRst2tex, cmdMd2html, cmdMd2tex}:
      ret = ret / htmldocsDir
    conf.outDir = ret

  ## process all commands
  case conf.cmd
-  of cmdBackends:
-    compileToBackend()
-    when BenchIC:
-      echoTimes graph.packed
+  of cmdBackends: compileToBackend()
  of cmdTcc:
    when hasTinyCBackend:
      extccomp.setCC(conf, "tcc", unknownLineInfo)
@@ -439,23 +402,6 @@ proc mainCommand*(graph: ModuleGraph) =
      for it in conf.searchPaths: msgWriteln(conf, it.string)
  of cmdCheck:
    commandCheck(graph)
-  of cmdM:
-    # cmdM uses NIF files, not ROD files
-    graph.config.symbolFiles = disabledSf
-    setUseIc(false)
-    commandCheck(graph)
-  of cmdNifC:
-    # Generate C code from NIF files
-    wantMainModule(conf)
-    setOutFile(conf)
-    commandNifC(graph)
-  of cmdDeps:
-    # Generate .build.nif for nifmake
-    wantMainModule(conf)
-    when not defined(nimKochBootstrap):
-      commandDeps(conf)
-    else:
-      rawMessage(conf, errGenerated, "nim deps not available in bootstrap build")
  of cmdParse:
    wantMainModule(conf)
    discard parseFile(conf.projectMainIdx, cache, conf)
--- a/compiler/mangleutils.nim
+++ b/compiler/mangleutils.nim
@@ -1,59 +0,0 @@
-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 #
--- a/compiler/modulegraphs.nim
+++ b/compiler/modulegraphs.nim
@@ -11,17 +11,11 @@
 ## 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, os, strutils, parseutils]
+import intsets, tables, hashes
 import ../dist/checksums/src/checksums/md5
-import ast, astalgo, options, lineinfos,idents, btrees, ropes, msgs, pathutils, packages, suggestsymdb
+import ast, astalgo, options, lineinfos,idents, btrees, ropes, msgs, pathutils, packages
 import ic / [packed_ast, ic]

-when not defined(nimKochBootstrap):
-  import ast2nif
-  import "../dist/nimony/src/lib" / [nifstreams, bitabs]
-
-import typekeys
-
 when defined(nimPreviewSlimSystem):
  import std/assertions

@@ -60,12 +54,15 @@ type
    concreteTypes*: seq[FullId]
    inst*: PInstantiation

+  SymInfoPair* = object
+    sym*: PSym
+    info*: TLineInfo
+
  PipelinePass* = enum
    NonePass
    SemPass
    JSgenPass
    CgenPass
-    NifgenPass
    EvalPass
    InterpreterPass
    GenDependPass
@@ -81,11 +78,8 @@ 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.
-    loadedOps: array[TTypeAttachedOp, Table[string, PSym]] # This can later by unified with `attachedOps` once it's stable
-    opsLog*: seq[LogEntry]
-    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)
+    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)
    enumToStringProcs*: Table[ItemId, LazySym]
    emittedTypeInfo*: Table[string, FileIndex]

@@ -95,8 +89,6 @@ 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
@@ -106,18 +98,12 @@ 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*: SuggestSymbolDatabase
+    suggestSymbols*: Table[FileIndex, seq[SymInfoPair]]
    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
@@ -142,11 +128,6 @@ type
    idgen*: IdGenerator
    operators*: Operators

-    cachedFiles*: StringTableRef
-
-    procGlobals*: seq[PNode]
-    nifReplayActions*: Table[int32, seq[PNode]]  # module position -> replay actions for NIF
-
  TPassContext* = object of RootObj # the pass's context
    idgen*: IdGenerator
  PPassContext* = ref TPassContext
@@ -166,13 +147,8 @@ proc resetForBackend*(g: ModuleGraph) =
  g.procInstCache.clear()
  for a in mitems(g.attachedOps):
    a.clear()
-  g.methodsPerGenericType.clear()
-  g.enumToStringProcs.clear()
-  g.dispatchers.setLen(0)
  g.methodsPerType.clear()
-  for a in mitems(g.loadedOps):
-    a.clear()
-  g.opsLog.setLen(0)
+  g.enumToStringProcs.clear()

 const
  cb64 = [
@@ -230,10 +206,10 @@ 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)
@@ -272,7 +248,7 @@ 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 = default(RodIter)
+    var rodIt: RodIter
    var r = initRodIterAllSyms(rodIt, g.config, g.cache, g.packed, FileIndex m.position, importHidden)
    while r != nil:
      yield r
@@ -289,30 +265,11 @@ 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 = default(ModuleIter)
+  var mi: ModuleIter
  var r = initModuleIter(mi, g, g.systemModule, name)
  while r != nil:
    yield r
@@ -343,7 +300,7 @@ 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)
@@ -362,38 +319,18 @@ 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.
  if g.attachedOps[op].contains(t.itemId):
    result = resolveAttachedOp(g, g.attachedOps[op][t.itemId])
-  elif g.config.cmd in {cmdNifC, cmdM}:
-    # Fall back to key-based lookup for NIF-loaded hooks
-    let key = typeKey(t, g.config, loadTypeCallback, loadSymCallback)
-    result = g.loadedOps[op].getOrDefault(key)
-    #echo "fallback ", key, " ", op, " ", result
  else:
    result = nil

 proc setAttachedOp*(g: ModuleGraph; module: int; t: PType; op: TTypeAttachedOp; value: PSym) =
  ## we also need to record this to the packed module.
-  if not g.attachedOps[op].contains(t.itemId):
-    let key = typeKey(t, g.config, loadTypeCallback, loadSymCallback)
-    # Use key-based deduplication for opsLog because different type objects
-    # (e.g. canon vs orig) can have different itemIds but same structural key
-    if key notin g.loadedOps[op]:
-      # Hooks should be written to the module where the type is defined,
-      # not the module that triggered the registration
-      let ownerModule = if t.sym != nil: t.sym.itemId.module.int else: module
-      g.opsLog.add LogEntry(kind: HookEntry, op: op, module: ownerModule, key: key, sym: value)
-      g.loadedOps[op][key] = value
  g.attachedOps[op][t.itemId] = LazySym(sym: value)

-proc setAttachedOp*(g: ModuleGraph; module: int; typeId: ItemId; op: TTypeAttachedOp; value: PSym) =
-  ## Overload that takes ItemId directly, useful for registering hooks from NIF index.
-  g.attachedOps[op][typeId] = LazySym(sym: value)
-
 proc setAttachedOpPartial*(g: ModuleGraph; module: int; t: PType; op: TTypeAttachedOp; value: PSym) =
  ## we also need to record this to the packed module.
  g.attachedOps[op][t.itemId] = LazySym(sym: value)
@@ -405,59 +342,20 @@ 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
-
-proc addNifReplayAction*(g: ModuleGraph; module: int32; n: PNode) =
-  ## Stores a replay action for NIF-based incremental compilation.
-  g.nifReplayActions.mgetOrPut(module, @[]).add n
-
-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

 proc setToStringProc*(g: ModuleGraph; t: PType; value: PSym) =
  g.enumToStringProcs[t.itemId] = LazySym(sym: value)
-  let key = typeKey(t, g.config, loadTypeCallback, loadSymCallback)
-  let ownerModule = if t.sym != nil: t.sym.itemId.module.int else: value.itemId.module.int
-  g.opsLog.add LogEntry(kind: EnumToStrEntry, module: ownerModule, key: key, sym: value)

 iterator methodsForGeneric*(g: ModuleGraph; t: PType): (int, PSym) =
-  if g.methodsPerGenericType.contains(t.itemId):
-    for it in mitems g.methodsPerGenericType[t.itemId]:
+  if g.methodsPerType.contains(t.itemId):
+    for it in mitems g.methodsPerType[t.itemId]:
      yield (it[0], resolveSym(g, it[1]))

 proc addMethodToGeneric*(g: ModuleGraph; module: int; t: PType; col: int; m: PSym) =
-  g.methodsPerGenericType.mgetOrPut(t.itemId, @[]).add (col, LazySym(sym: m))
-  let key = typeKey(t, g.config, loadTypeCallback, loadSymCallback)
-  let ownerModule = if t.sym != nil: t.sym.itemId.module.int else: module
-  g.opsLog.add LogEntry(kind: MethodEntry, module: ownerModule, key: key, sym: m)
-
-proc logGenericInstance*(g: ModuleGraph; inst: PSym) =
-  ## Log a generic instance so it gets written to the NIF file.
-  ## This is needed when generic instances are created during compile-time
-  ## evaluation and may be referenced from other modules compiled in the same run.
-  if g.config.cmd in {cmdNifC, cmdM}:
-    let ownerModule = inst.itemId.module.int
-    g.opsLog.add LogEntry(kind: GenericInstEntry, module: ownerModule, sym: inst)
+  g.methodsPerType.mgetOrPut(t.itemId, @[]).add (col, LazySym(sym: m))

 proc hasDisabledAsgn*(g: ModuleGraph; t: PType): bool =
  let op = getAttachedOp(g, t, attachedAsgn)
@@ -471,33 +369,10 @@ proc copyTypeProps*(g: ModuleGraph; module: int; dest, src: PType) =

 proc loadCompilerProc*(g: ModuleGraph; name: string): PSym =
  result = nil
-  if g.config.symbolFiles == disabledSf and optWithinConfigSystem notin g.config.globalOptions:
-    # For NIF-based compilation, search in loaded NIF modules
-    when not defined(nimKochBootstrap):
-      # Only try to resolve from NIF if we're actually using NIF files (cmdNifC)
-      if g.config.cmd == cmdNifC:
-        # First try system module (most compilerprocs are there)
-        let systemFileIdx = g.config.m.systemFileIdx
-        if systemFileIdx != InvalidFileIdx:
-          result = tryResolveCompilerProc(ast.program, name, systemFileIdx)
-          if result != nil:
-            strTableAdd(g.compilerprocs, result)
-            return result
-
-        # Try threadpool module (some compilerprocs like FlowVar are there)
-        # Find threadpool module by searching loaded modules
-        for moduleIdx in 0..<g.ifaces.len:
-          let module = g.ifaces[moduleIdx].module
-          if module != nil and module.name.s == "threadpool":
-            let threadpoolFileIdx = module.position.FileIndex
-            result = tryResolveCompilerProc(ast.program, name, threadpoolFileIdx)
-            if result != nil:
-              strTableAdd(g.compilerprocs, result)
-              return result
-    return nil
+  if g.config.symbolFiles == disabledSf: return nil

  # slow, linear search, but the results are cached:
-  for module in 0..<len(g.packed):
+  for module in 0..high(g.packed):
    #if isCachedModule(g, module):
    let x = searchForCompilerproc(g.packed[module], name)
    if x >= 0:
@@ -528,10 +403,10 @@ template getPContext(): untyped =
  else: c.c

 when defined(nimsuggest):
-  template onUse*(info: TLineInfo; s: PSym; isGenericInstance = false) = discard
+  template onUse*(info: TLineInfo; s: PSym) = discard
  template onDefResolveForward*(info: TLineInfo; s: PSym) = discard
 else:
-  template onUse*(info: TLineInfo; s: PSym; isGenericInstance = false) = discard
+  template onUse*(info: TLineInfo; s: PSym) = discard
  template onDef*(info: TLineInfo; s: PSym) = discard
  template onDefResolveForward*(info: TLineInfo; s: PSym) = discard

@@ -546,49 +421,6 @@ 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
@@ -597,12 +429,11 @@ proc registerModule*(g: ModuleGraph; m: PSym) =
    setLen(g.ifaces, m.position + 1)

  if m.position >= g.packed.len:
-    setLen(g.packed.pm, m.position + 1)
+    setLen(g.packed, m.position + 1)

-  if g.ifaces[m.position].module == nil:
-    g.ifaces[m.position] = Iface(module: m, converters: @[], patterns: @[],
-                                uniqueName: rope(uniqueModuleName(g.config, m)))
-    initStrTables(g, m)
+  g.ifaces[m.position] = Iface(module: m, converters: @[], patterns: @[],
+                               uniqueName: rope(uniqueModuleName(g.config, FileIndex(m.position))))
+  initStrTables(g, m)

 proc registerModuleById*(g: ModuleGraph; m: FileIndex) =
  registerModule(g, g.packed[int m].module)
@@ -610,21 +441,19 @@ proc registerModuleById*(g: ModuleGraph; m: FileIndex) =
 proc initOperators*(g: ModuleGraph): Operators =
  # These are safe for IC.
  # Public because it's used by DrNim.
-  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)
-  )
+  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)

 proc initModuleGraphFields(result: ModuleGraph) =
  # A module ID of -1 means that the symbol is not attached to a module at all,
@@ -637,7 +466,7 @@ proc initModuleGraphFields(result: ModuleGraph) =
  result.importStack = @[]
  result.inclToMod = initTable[FileIndex, FileIndex]()
  result.owners = @[]
-  result.suggestSymbols = initTable[FileIndex, SuggestFileSymbolDatabase]()
+  result.suggestSymbols = initTable[FileIndex, seq[SymInfoPair]]()
  result.suggestErrors = initTable[FileIndex, seq[Suggest]]()
  result.methods = @[]
  result.compilerprocs = initStrTable()
@@ -651,14 +480,12 @@ proc initModuleGraphFields(result: ModuleGraph) =
  result.symBodyHashes = initTable[int, SigHash]()
  result.operators = initOperators(result)
  result.emittedTypeInfo = initTable[string, FileIndex]()
-  result.cachedFiles = newStringTable()

 proc newModuleGraph*(cache: IdentCache; config: ConfigRef): ModuleGraph =
  result = ModuleGraph()
  result.config = config
  result.cache = cache
  initModuleGraphFields(result)
-  ast.setupProgram(config, cache)

 proc resetAllModules*(g: ModuleGraph) =
  g.packageSyms = initStrTable()
@@ -754,13 +581,13 @@ proc markDirty*(g: ModuleGraph; fileIdx: FileIndex) =
  if m != nil:
    g.suggestSymbols.del(fileIdx)
    g.suggestErrors.del(fileIdx)
-    incl m.flagsImpl, sfDirty
+    incl m.flags, sfDirty

 proc unmarkAllDirty*(g: ModuleGraph) =
  for i in 0i32..<g.ifaces.len.int32:
    let m = g.ifaces[i].module
    if m != nil:
-      m.flagsImpl.excl sfDirty
+      m.flags.excl sfDirty

 proc isDirty*(g: ModuleGraph; m: PSym): bool =
  result = g.suggestMode and sfDirty in m.flags
@@ -813,52 +640,11 @@ proc moduleFromRodFile*(g: ModuleGraph; fileIdx: FileIndex;
  else:
    result = nil

-when not defined(nimKochBootstrap):
-  proc moduleFromNifFile*(g: ModuleGraph; fileIdx: FileIndex;
-                          flags: set[LoadFlag] = {}): PrecompiledModule =
-    ## Returns 'nil' if the module needs to be recompiled.
-    ## Loads module from NIF file when optCompress is enabled.
-    ## When loadFullAst is true, loads the complete module AST for code generation.
-    if not fileExists(toNifFilename(g.config, fileIdx)):
-      return PrecompiledModule(module: nil)
-
-    # Create module symbol
-    let filename = AbsoluteFile toFullPath(g.config, fileIdx)
-
-    let m = PSym(
-      kindImpl: skModule,
-      itemId: ItemId(module: int32(fileIdx), item: 0'i32),
-      name: getIdent(g.cache, splitFile(filename).name),
-      infoImpl: newLineInfo(fileIdx, 1, 1),
-      positionImpl: int(fileIdx))
-    setOwner(m, getPackage(g.config, g.cache, fileIdx))
-    # Register module in graph
-    registerModule(g, m)
-
-    result = loadNifModule(ast.program, fileIdx,
-                           g.ifaces[fileIdx.int].interf,
-                           g.ifaces[fileIdx.int].interfHidden, flags)
-    result.module = m
-
-    # Register hooks from NIF index with the module graph
-    for x in result.logOps:
-      case x.kind
-      of HookEntry:
-        g.loadedOps[x.op][x.key] = x.sym
-      of ConverterEntry:
-        g.ifaces[fileIdx.int].converters.add LazySym(sym: x.sym)
-      of MethodEntry:
-        discard "todo"
-      of EnumToStrEntry:
-        discard "todo"
-      of GenericInstEntry:
-        raiseAssert "GenericInstEntry should not be in the NIF index"
-    # Register methods per type from NIF index
-    discard "todo"
-
 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")
@@ -880,18 +666,20 @@ proc getPackage*(graph: ModuleGraph; fileIdx: FileIndex): PSym =
    result = pkgSym
    graph.packageSyms.strTableAdd(pkgSym)

-proc belongsToStdlib*(graph: ModuleGraph, sym: PSym): bool =
+func belongsToStdlib*(graph: ModuleGraph, sym: PSym): bool =
  ## Check if symbol belongs to the 'stdlib' package.
  sym.getPackageSymbol.getPackageId == graph.systemModule.getPackageId

-proc fileSymbols*(graph: ModuleGraph, fileIdx: FileIndex): SuggestFileSymbolDatabase =
-  result = graph.suggestSymbols.getOrDefault(fileIdx, newSuggestFileSymbolDatabase(fileIdx, optIdeExceptionInlayHints in graph.config.globalOptions))
-  doAssert(result.fileIndex == fileIdx)
+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, @[])

 iterator suggestSymbolsIter*(g: ModuleGraph): SymInfoPair =
  for xs in g.suggestSymbols.values:
-    for i in xs.lineInfo.low..xs.lineInfo.high:
-      yield xs.getSymInfoPair(i)
+    for x in xs:
+      yield x

 iterator suggestErrorsIter*(g: ModuleGraph): Suggest =
  for xs in g.suggestErrors.values:
--- a/compiler/modulepaths.nim
+++ b/compiler/modulepaths.nim
@@ -7,11 +7,9 @@
 #    distribution, for details about the copyright.
 #

-import ast, renderer, msgs, options, idents, lineinfos,
+import ast, renderer, strutils, msgs, options, idents, os, 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"
@@ -38,18 +36,11 @@ proc getModuleName*(conf: ConfigRef; n: PNode): string =
          localError(n.info, "only '/' supported with $package notation")
          result = ""
    else:
-      if n0.kind in nkIdentKinds:
-        let ident = n0.getPIdent
-        if ident != nil and ident.s[0] == '/':
-          let modname = getModuleName(conf, n[2])
-          # hacky way to implement 'x / y /../ z':
-          result = getModuleName(conf, n1)
-          result.add renderTree(n0, {renderNoComments}).replace(" ")
-          result.add modname
-        else:
-          result = ""
-      else:
-        result = ""
+      let modname = getModuleName(conf, n[2])
+      # hacky way to implement 'x / y /../ z':
+      result = getModuleName(conf, n1)
+      result.add renderTree(n0, {renderNoComments}).replace(" ")
+      result.add modname
  of nkPrefix:
    when false:
      if n[0].kind == nkIdent and n[0].ident.s == "$":
@@ -79,10 +70,6 @@ proc checkModuleName*(conf: ConfigRef; n: PNode; doLocalError=true): FileIndex =
  else:
    result = fileInfoIdx(conf, fullPath)

-type
-  SelectedBase = enum
-    FromProject, FromSearchPath, FromNimblePath
-
 proc mangleModuleName*(conf: ConfigRef; path: AbsoluteFile): string =
  ## Mangle a relative module path to avoid path and symbol collisions.
  ##
@@ -91,27 +78,9 @@ proc mangleModuleName*(conf: ConfigRef; path: AbsoluteFile): string =
  ##
  ## Example:
  ## `foo-#head/../bar` becomes `@foo-@hhead@s..@sbar`
-  var best = relativeTo(path, conf.projectPath).string
-  var selectedBase = FromProject
-  for x in conf.searchPaths:
-    let other = relativeTo(path, x).string
-    if other.len < best.len:
-      best = other
-      selectedBase = FromSearchPath
-  for x in conf.nimblePaths:
-    let other = relativeTo(path, x).string
-    if other.len < best.len:
-      best = other
-      selectedBase = FromNimblePath
-  let prefix =
-    case selectedBase
-    of FromProject: "@m"
-    of FromSearchPath: "@p"
-    of FromNimblePath: "@n"
-
-  prefix & best.multiReplace(
+  "@m" & relativeTo(path, conf.projectPath).string.multiReplace(
    {$os.DirSep: "@s", $os.AltSep: "@s", "#": "@h", "@": "@@", ":": "@c"})

 proc demangleModuleName*(path: string): string =
  ## Demangle a relative module path.
-  result = path.multiReplace({"@@": "@", "@h": "#", "@s": "/", "@m": "", "@p": "", "@n": "", "@c": ":"})
+  result = path.multiReplace({"@@": "@", "@h": "#", "@s": "/", "@m": "", "@c": ":"})
--- a/compiler/modules.nim
+++ b/compiler/modules.nim
@@ -14,9 +14,6 @@ import
  idents, lexer, syntaxes, modulegraphs,
  lineinfos, pathutils

-import ../dist/checksums/src/checksums/sha1
-import std/strtabs
-
 proc resetSystemArtifacts*(g: ModuleGraph) =
  magicsys.resetSysTypes(g)

@@ -25,16 +22,16 @@ template getModuleIdent(graph: ModuleGraph, filename: AbsoluteFile): PIdent =

 proc partialInitModule*(result: PSym; graph: ModuleGraph; fileIdx: FileIndex; filename: AbsoluteFile) =
  let packSym = getPackage(graph, fileIdx)
-  setOwner(result, packSym)
+  result.owner = packSym
  result.position = int fileIdx

 proc newModule*(graph: ModuleGraph; fileIdx: FileIndex): PSym =
  let filename = AbsoluteFile toFullPath(graph.config, fileIdx)
  # We cannot call ``newSym`` here, because we have to circumvent the ID
  # mechanism, which we do in order to assign each module a persistent ID.
-  result = PSym(kindImpl: skModule, itemId: ItemId(module: int32(fileIdx), item: 0'i32),
+  result = PSym(kind: skModule, itemId: ItemId(module: int32(fileIdx), item: 0'i32),
                name: getModuleIdent(graph, filename),
-                infoImpl: newLineInfo(fileIdx, 1, 1))
+                info: newLineInfo(fileIdx, 1, 1))
  if not isNimIdentifier(result.name.s):
    rawMessage(graph.config, errGenerated, "invalid module name: '" & result.name.s &
              "'; a module name must be a valid Nim identifier.")
@@ -45,8 +42,6 @@ proc includeModule*(graph: ModuleGraph; s: PSym, fileIdx: FileIndex): PNode =
  result = syntaxes.parseFile(fileIdx, graph.cache, graph.config)
  graph.addDep(s, fileIdx)
  graph.addIncludeDep(s.position.FileIndex, fileIdx)
-  let path = toFullPath(graph.config, fileIdx)
-  graph.cachedFiles[path] = $secureHashFile(path)

 proc wantMainModule*(conf: ConfigRef) =
  if conf.projectFull.isEmpty:
--- a/Show More
+++ b/Show More
Author	SHA1	Message	Date
ringabout	88f556b486	merge upstream code	2023-10-04 15:07:11 +08:00
ringabout	343b304461	Merge remote-tracking branch 'upstream/araq-nir' into pr_ast2ir	2023-10-04 15:03:36 +08:00
Araq	37e3573b61	NIR: implemented builtin	2023-10-03 23:57:38 +02:00
ringabout	09d40ea41b	adds entry point and debug code	2023-10-03 22:27:19 +08:00
Araq	326a4592f1	progress	2023-10-03 09:08:20 +02:00
araq	df71f4602e	baby steps	2023-10-02 14:23:42 +02:00
araq	f496c0e14c	progress	2023-10-01 12:53:38 +02:00
araq	9d9d860797	support for annotations that can be used for calling conventions	2023-10-01 10:34:37 +02:00
araq	ef5c4ffaa2	same chance recursive types work [CI skip]	2023-10-01 09:41:37 +02:00
Araq	95c9d4cd7b	bugfix	2023-10-01 07:49:05 +02:00
araq	7f92d26470	type generation for closures	2023-10-01 01:43:06 +02:00
araq	284bbe2eb7	some varargs handling	2023-10-01 01:28:19 +02:00
araq	42ebed76e6	progress	2023-10-01 01:15:53 +02:00
araq	4fada54c6b	WIP: translate the AST into the IR	2023-10-01 00:06:56 +02:00
araq	9510e1a55c	NIR: An immediate representation for Nim. WIP	2023-09-30 21:02:01 +02:00