Docker Images for C++ CI Workflows

This repository provides Docker images optimized for use in GitHub Actions CI workflows targeting C++ projects.

All images are built on top of a common Ubuntu 24.04 base with several useful packages installed via APT:

• binutils
• bison
• cmake
• conan (installed via pipx)
• flex
• git
• make
• ninja
• pkgconf

GCC images

• ghcr.io/mattkretz/cplusplus-ci/gcc9
• ghcr.io/mattkretz/cplusplus-ci/gcc10
• ghcr.io/mattkretz/cplusplus-ci/gcc11
• ghcr.io/mattkretz/cplusplus-ci/gcc12
• ghcr.io/mattkretz/cplusplus-ci/gcc13
• ghcr.io/mattkretz/cplusplus-ci/gcc14
• ghcr.io/mattkretz/cplusplus-ci/gcc15
• ghcr.io/mattkretz/cplusplus-ci/gcc16

The GCC images provide gcc and g++ aliases to the respective version. GCC is always installed with multilib support, i.e. -m32, -mx32, and -m64 are supported.

Clang images

• ghcr.io/mattkretz/cplusplus-ci/clang14
• ghcr.io/mattkretz/cplusplus-ci/clang15
• ghcr.io/mattkretz/cplusplus-ci/clang16
• ghcr.io/mattkretz/cplusplus-ci/clang17
• ghcr.io/mattkretz/cplusplus-ci/clang18
• ghcr.io/mattkretz/cplusplus-ci/clang19
• ghcr.io/mattkretz/cplusplus-ci/clang20
• ghcr.io/mattkretz/cplusplus-ci/clang21
• ghcr.io/mattkretz/cplusplus-ci/clang22

The Clang images provide clang, clang++, clang-tidy, and clang-format aliases to the respective version.

Deprecated images

The ghcr.io/mattkretz/cplusplus-ci/base and ghcr.io/mattkretz/cplusplus-ci/latest images are deprecated and will not be updated anymore.

---

Example GitHub CI Workflow

name: Clang

on:
  push:
    branches: [ main ]
  pull_request:

jobs:
  clang:
    strategy:
      fail-fast: false
      matrix:
        version: [20, 21]

    runs-on: ubuntu-latest

    container:
      image: ghcr.io/mattkretz/cplusplus-ci/clang${{ matrix.version }}

    steps:
      - uses: actions/checkout@v4

      - name: Run test suite
        env:
          CXX: clang++
        run: make check

Latest CMake

If you want to use latest CMake add the following step to your workflow before a step that needs cmake:

      - name: Set PATH for cmake-latest
        run: echo /opt/cmake-latest/bin >> $GITHUB_PATH

Updates

The gcc15 and gcc16 images are updated once per week. All other images are updated once per month. There may also be manual updates whenever the feature set needs to change.