install-llvm-action

A GitHub Action for downloading and installing LLVM and Clang binaries.

Supports LLVM and Clang 7.1.0 and later. The binaries will be added to the relevant environment variables for the platform after installation (e.g., PATH, LD_LIBRARY_PATH, and/or DYLD_LIBRARY_PATH).

Released under the Apache License 2.0.

Note: As mentioned in the notes for recent llvm/llvm-project releases, LLVM and Clang binaries are provided by volunteers and there is no guarantee of the availability of pre-built binaries for every platform and for every LLVM and Clang release. The LLVM and Clang versions currently supported by this action can be found in the assets.json file. Note that availability of pre-built binaries can also differ depending on the targeted operating system and processor architecture (e.g., x86-64 vs ARM64).

Example Usage

- name: Install LLVM and Clang
  uses: KyleMayes/install-llvm-action@v2
  with:
    version: "10.0"

Example Usage (with non-default installation directory):

- name: Install LLVM and Clang
  uses: KyleMayes/install-llvm-action@v2
  with:
    version: "10.0"
    directory: ${{ runner.temp }}/llvm

Linking to Installed Libraries (Linux)

If your build system requires a library from the installed LLVM and Clang binaries such as libclang.so, and it fails to find it, then it may help to create a symlink for the versioned .so using the following step which utilizes the LLVM_PATH environment variable set by this action:

- name: Symlink libclang.so (Linux)
  if: contains(matrix.os, 'ubuntu')
  run: sudo ln -s libclang-11.so.1 /lib/x86_64-linux-gnu/libclang.so
  working-directory: ${{ env.LLVM_PATH }}/lib

Inputs

version

Required The version of LLVM and Clang binaries to install.

This can be a specific LLVM and Clang version such as 10.1.2 or a minimum version like 10.1 or just 10. When specifying a minimum version, the highest compatible version supported by the platform will be installed (e.g., 10.1.2 for 10.1 or 10.2.0 for 10).

Note that when using minimum versions like 10 the specific version installed by this action may not be the same on every operating system and architecture (e.g., x86-86 vs ARM64). This is because some versions of the LLVM and Clang binaries do not exist for some operating systems. You can view this file to see the currently supported LLVM and Clang versions for each operating system and architecture pairing.

arch

The archtecture (either x64 or arm64) to install LLVM and Clang binaries for.

By default, the architecture of the machine this action is running on will be used.

force-url

The full download URL to use for LLVM and Clang binaries.

If this input is used, the version, arch, and mirror-url inputs will be ignored (except in that the value of the version input will be used verbatim as the value for the version output). Instead, the URL supplied for this input is assumed to be a full URL to download LLVM and Clang binaries. This input can be used if this action lacks support for a recent LLVM and Clang version or if you have LLVM and Clang binaries mirror in a way that can't be handled by the mirror-url input.

directory

The directory to install LLVM and Clang binaries to. If not provided, C:\Program Files\LLVM is used as the default value on Windows and ./llvm is used on other operating systems.

This action puts the value of this input into the LLVM_PATH environment variable which allows for easy use of the directory containing the LLVM and Clang binaries in subsequent jobs (e.g., ${{ env.LLVM_PATH }}).

cached

Whether the LLVM and Clang binaries were cached.

Note: Caching is not currently recommended, it is usually slower than just directly downloading the LLVM and Clang binaries.

mirror-url

The base URL to download LLVM and Clang binaries from instead of using GitHub.

This can be used if you want to download the LLVM and Clang binaries from a mirror of the GitHub releases for the llvm/llvm-project repository provided by a service like Artifactory.

auth

The Authorization header to use when downloading LLVM and Clang binaries.

This is unnecessary unless you are providing the mirror-url input and you need to provide an Authorization header when downloading the LLVM and Clang binaries from the service targeted by that custom download URL.

env

Whether to set CC and CXX environment variables to Clang paths.

Outputs

version

The full version of LLVM and Clang binaries installed.

This will only differ from the value of the version input when specifying a minimum version like 10.1 or 10.