llvmmacos-sierra

How to install LLVM for Mac?

How do I install LLVM on macOS Sierra? I've tried brew install llvm but when trying to use an llvm command like lli I get a command not found error.

Solution

  • homebrew does not link llvm to /usr/local/bin because it may conflict with the system one, causing all kinds of nasty bugs. Instead, you should use the full path to invoke them, such as /usr/local/opt/llvm/bin/lli.

    In fact there's a Caveat that's now listed which spells this out...

    ==> Caveats
    ==> llvm

    To use the bundled libc++ please add the following LDFLAGS:
    LDFLAGS="-L/usr/local/opt/llvm/lib -Wl,-rpath,/usr/local/opt/llvm/lib"

    llvm is keg-only, which means it was not symlinked into /usr/local, because macOS already provides this software and installing another version in parallel can cause all kinds of trouble.

    If you need to have llvm first in your PATH run:
    echo 'export PATH="/usr/local/opt/llvm/bin:$PATH"' >> ~/.bash_profile

    For compilers to find llvm you may need to set:
    export LDFLAGS="-L/usr/local/opt/llvm/lib"
    export CPPFLAGS="-I/usr/local/opt/llvm/include"