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When compiling with CMAKE_BUILD_TYPE=RelWithDebInfo, several -Wmaybe-uninitialized warnings are printed. These were thought to be false positives (#5061); there are no control paths that lead to an uninitialized value. However, when gcc is run in -O2 mode, it makes a mistake while generating the necessary logic. Specifically, for the code: ... int = 0; // Index of the server whose address equals addr. for (; i < watchers.ga_len; i++) { watcher = ((SocketWatcher **)watchers.ga_data)[i]; // <snip> } if (i >= watchers.ga_len) { ELOG("Not listening on %s", addr); return; } ... Gcc generates: ... <+98>: cmp %ebx, %ebp <+100>: jg 0x530f13 <server_stop+55> <+102>: cmp %ebp, ebx <+104>: jl 0x530f7e <server_stop+162> ... Normally, the if statement should catch the only control path where watcher is not assigned: watchers.ga_len <= 0. When compiled, the assembly lines 98 and 100 correspond to checking if i < watchers.ga_len, and the lines 102 and 104 correspond to checking if i >= watchers.ga_len. The assembly seems to compare ebp (which is watchers.ga_len) with ebx (which is i), and jump if greater; then do the same comparison and jump if less. This is where gcc makes a mistake: it flips the order of the cmp instruction. This means that the REAL behavior is first check if i < watchers.ga_len and then check if i < watchers.ga_len. Which means the code inside the if statement is NEVER executed; no combination of i and watchers.ga_len will ever trigger ELOG(). So not only is this a use of an uninitialized value if watchers.ga_len == 0 (or technically, if it's less than zero too), it also clobbers any error detection if the for loop reaches the last entry (which would normally cause i == watchers.ga_len too). This commit fixes this issue by adding a bool to keep track of whether a watcher was found during the loop. This makes gcc generate the correct code, avoiding both bugs.
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Neovim is a project that seeks to aggressively refactor Vim in order to:
- Simplify maintenance and encourage contributions
- Split the work between multiple developers
- Enable advanced UIs without modifications to the core
- Maximize extensibility
See the wiki and Roadmap for more information.
Install from source
make CMAKE_BUILD_TYPE=RelWithDebInfo
sudo make install
To install to a non-default location, specify CMAKE_INSTALL_PREFIX:
make CMAKE_EXTRA_FLAGS="-DCMAKE_INSTALL_PREFIX=/full/path/"
make install
See the wiki for details.
Install from package
Pre-built packages for Windows, macOS, and Linux are found at the Releases page.
Managed packages are in Homebrew, Debian, Ubuntu, Fedora, Arch Linux, Gentoo, and more!
Project layout
├─ ci/ build automation
├─ cmake/ build scripts
├─ runtime/ user plugins/docs
├─ src/ application source code (see src/nvim/README.md)
│ ├─ api/ API subsystem
│ ├─ eval/ VimL subsystem
│ ├─ event/ event-loop subsystem
│ ├─ generators/ code generation (pre-compilation)
│ ├─ lib/ generic data structures
│ ├─ lua/ lua subsystem
│ ├─ msgpack_rpc/ RPC subsystem
│ ├─ os/ low-level platform code
│ └─ tui/ built-in UI
├─ third-party/ cmake subproject to build dependencies
└─ test/ tests (see test/README.md)
- To disable
third-party/specifyUSE_BUNDLED_DEPS=NOorUSE_BUNDLED=NO(CMake option).
Features
- Modern GUIs
- API access from any language including clojure, lisp, go, haskell, lua, javascript, perl, python, ruby, rust.
- Embedded, scriptable terminal emulator
- Asynchronous job control
- Shared data (shada) among multiple editor instances
- XDG base directories support
- Compatible with most Vim plugins, including Ruby and Python plugins.
See :help nvim-features for the full list!
License
Neovim is licensed under the terms of the Apache 2.0 license, except for parts that were contributed under the Vim license.
-
Contributions committed before b17d96 remain under the Vim license.
-
Contributions committed after b17d96 are licensed under Apache 2.0 unless those contributions were copied from Vim (identified in the commit logs by the
vim-patchtoken).
See LICENSE for details.
Vim is Charityware. You can use and copy it as much as you like, but you are
encouraged to make a donation for needy children in Uganda. Please see the
kcc section of the vim docs or visit the ICCF web site, available at these URLs:
http://iccf-holland.org/
http://www.vim.org/iccf/
http://www.iccf.nl/
You can also sponsor the development of Vim. Vim sponsors can vote for
features. The money goes to Uganda anyway.