Clang

Catalog v8.

Installs Clang with clangd, clang-format, clang-tidy and LLDB next to GCC.

Select

[toolchains]
clang = "22"

Choose the line in the [toolchains] table of limanix.toml and apply the change. The module brings GCC with its build tools and native library support; cc and c++ stay GCC. Choose the GCC line with gcc in the same table.

Versions

Value	Clang	Notes
22	22.x	Recommended
21	21.x	End of life
20	20.x	End of life

Lines come from the base Nixpkgs revision. The LLVM project maintains only its newest release; selecting an older line prints a warning when the VM is built.

Use

Inside the VM:

clang++ -std=c++23 -o app main.cpp
CC=clang CXX=clang++ cmake -B build -G Ninja
clang-format -i main.cpp

On Linux, Clang uses the C++ standard library and the startup files of GCC. It finds the headers and libraries of [nixos] packages the same way as GCC.

Editor support

The clangd of the selected line replaces the one that comes with GCC. It runs clang-tidy checks when the project has a .clang-tidy file.

Configuration and integration

Boundary	Contract
Public capability	lmx.capabilities.languageSupport.tools.clangd from the selected line, preferred over the GCC one
Integration	Imports GCC; cc and c++ remain GCC
Compilers	clang and clang++ search /run/current-system/sw like GCC
Services	No daemon