llvm@21

About

Install llvm@21 on macOS with Homebrew Formula using `brew install llvm@21`. llvm@21 is a Development command-line package with version 21.1.8. The package is listed in homebrew/core.

Dependencies

Build Dependencies

Installation Notes

CLANG_CONFIG_FILE_SYSTEM_DIR: $HOMEBREW_PREFIX/etc/clang
CLANG_CONFIG_FILE_USER_DIR:   ~/.config/clang

LLD is now provided in a separate formula:
  brew install lld@21

Using `clang`, `clang++`, etc., requires a CLT installation at `/Library/Developer/CommandLineTools`.
If you don't want to install the CLT, you can write appropriate configuration files pointing to your
SDK at ~/.config/clang.

To use the bundled libunwind please use the following LDFLAGS:
  LDFLAGS="-L$HOMEBREW_PREFIX/opt/llvm@21/lib/unwind -lunwind"

To use the bundled libc++ please use the following LDFLAGS:
  LDFLAGS="-L$HOMEBREW_PREFIX/opt/llvm@21/lib/c++ -L$HOMEBREW_PREFIX/opt/llvm@21/lib/unwind -lunwind"
Features newer than system libc++ will require the following define to enable:
  CPPFLAGS="-D_LIBCPP_DISABLE_AVAILABILITY"

NOTE: You probably want to use the libunwind and libc++ provided by macOS unless you know what you're doing.

Frequently asked questions