Fix CI and build with modern cmake

.github/workflows/ci.yml

@@ -1,73 +1,48 @@
 name: CI
 on: [push, pull_request]
 
-jobs:
-  # Here we're keeping on arbitrary LLVM version fixed and varying GCC.
-  linux-gcc:
-    strategy:
-      fail-fast: false
-      matrix:
-        image:
-          # List: https://github.com/conan-io/conan-docker-tools
-          - gcc10
-          - gcc9
-          - gcc8
-          - gcc7
-          - gcc6
-
-    runs-on: ubuntu-latest
-    container:
-      image: conanio/${{matrix.image}}
-      options: --user root
-
-    steps:
-    - uses: actions/checkout@v2
-    - name: Create Build Environment
-      run: cmake -E make_directory build
-    - name: Install libclang
-      run: apt-get -qq update && apt-get install -y llvm clang libclang-dev
-    - name: Install ninja
-      run: type ninja || apt-get install -y ninja-build
+concurrency:
+  group: ci-${{ github.ref }}
+  cancel-in-progress: true
 
-    - name: Configure
-      working-directory: build/
-      run: cmake -GNinja $GITHUB_WORKSPACE
-    - name: Build
-      working-directory: build/
-      run: cmake --build .
-    - name: Test
-      working-directory: build/
-      run: ctest --output-on-failure
-
-  # Here we're varying the LLVM version and using its clang for compiling as well.
-  linux-clang:
+jobs:
+  test:
+    runs-on: ${{ matrix.on }}
     strategy:
-      fail-fast: false
       matrix:
-        version: [7, 8, 9, 10]
-
-    runs-on: ubuntu-latest
-    container:
-      # Just one of the newer images.
-      image: conanio/gcc10
-      options: --user root
+        include:
+        - { environment: "llvm-15", on: "ubuntu-24.04" }
+        - { environment: "llvm-16", on: "ubuntu-24.04" }
+        - { environment: "llvm-17", on: "ubuntu-24.04" }
+        - { environment: "llvm-18", on: "ubuntu-24.04" }
+        - { environment: "llvm-19", on: "ubuntu-24.04" }
+        - { environment: "llvm-20", on: "ubuntu-24.04" }
+        - { environment: "llvm-21", on: "ubuntu-24.04" }
+        - { environment: "llvm-22", on: "ubuntu-24.04" }
+        # The Xcode 16.x SDK is not compatible with such an old clang
+        # - { environment: "llvm-15", on: "macos-15" }
+        # - { environment: "llvm-16", on: "macos-15" }
+        # - { environment: "llvm-17", on: "macos-15" }
+        # - { environment: "llvm-18", on: "macos-15" }
+        - { environment: "llvm-19", on: "macos-15" }
+        # conda cannot solve for clangdev=20,21,22 on Silicon
+        # - { environment: "llvm-20", on: "macos-15" }
+        # - { environment: "llvm-21", on: "macos-15" }
+        # - { environment: "llvm-22", on: "macos-15" }
+        # The Xcode 16.x SDK is not compatible with such an old clang
+        # - { environment: "llvm-15", on: "macos-15-intel" }
+        # - { environment: "llvm-16", on: "macos-15-intel" }
+        # - { environment: "llvm-17", on: "macos-15-intel" }
+        # - { environment: "llvm-18", on: "macos-15-intel" }
+        - { environment: "llvm-19", on: "macos-15-intel" }
+        - { environment: "llvm-20", on: "macos-15-intel" }
+        - { environment: "llvm-21", on: "macos-15-intel" }
+        - { environment: "llvm-22", on: "macos-15-intel" }
 
     steps:
-    - uses: actions/checkout@v2
-    - name: Create Build Environment
-      run: cmake -E make_directory build
-    - name: Install libclang
-      run: apt-get -qq update && apt-get install -y llvm-${{matrix.version}} clang-${{matrix.version}} libclang-${{matrix.version}}-dev
-    - name: Install ninja
-      run: type ninja || apt-get install -y ninja-build
-
-    - name: Configure
-      working-directory: build/
-      run: cmake -GNinja $GITHUB_WORKSPACE -DCMAKE_CXX_COMPILER=clang++-${{matrix.version}}
-    - name: Build
-      working-directory: build/
-      run: cmake --build .
-    - name: Test
-      working-directory: build/
-      run: ctest --output-on-failure
-
+    - uses: actions/checkout@v5
+      with: { submodules: recursive }
+    - uses: prefix-dev/setup-pixi@v0.9.4
+      with: { pixi-version: v0.68.0 }
+    - name: run tests
+      run: pixi run -e ${{ matrix.environment }} test

.gitignore

@@ -0,0 +1,2 @@
+/build
+/Testing

CMakeLists.txt

@@ -2,7 +2,7 @@
 # SPDX-License-Identifier: MIT
 # found in the top-level directory of this distribution.
 
-cmake_minimum_required(VERSION 3.11)
+cmake_minimum_required(VERSION 4.0)
 project(cppast VERSION 0.1.0)
 
 if(CMAKE_CURRENT_SOURCE_DIR STREQUAL CMAKE_SOURCE_DIR)

README.md

@@ -40,23 +40,17 @@ TODO, refer to documentation comments in header file.
 
 ### Installation
 
-The library can be used as CMake subdirectory, download it and call `add_subdirectory(path/to/cppast)`, then link to the `cppast` target and enable C++11 or higher.
+For development, we recommend to use [pixi](https://pixi.sh). Run `pixi run build` to compile the package, `pixi run test` to run its test suite, `pixi run cppast` to run the cppast tool.
 
-The parser needs `libclang` and the `clang++` binary, at least version 4.0.0.
-The `clang++` binary will be found in `PATH` and in the same directory as the program that is being executed.
+The library can also be used as CMake subdirectory, download it and call `add_subdirectory(path/to/cppast)`, then link to the `cppast` target and enable C++11 or higher.
 
-*Note: The project will drop support for older LLVM versions very soon; this minimizes the workaround code when the `libclang` API catches up.*
+The parser needs `libclang` and the `clang++` binary, at least version 15.
+The `clang++` binary will be found in `PATH` and in the same directory as the program that is being executed.
 
 The CMake code requires `llvm-config`, you may need to install `llvm` and not just `clang` to get it (e.g. on ArchLinux).
 If `llvm-config` is in your path and the version is compatible, it should just work out of the box.
 Else you need to set the CMake variable `LLVM_CONFIG_BINARY` to the proper path.
 
-If you don't have a proper clang version installed, it can also be downloaded.
-For that you need to set `LLVM_DOWNLOAD_OS_NAME`.
-This is the name of the operating system used on the [LLVM pre-built binary archive](http://releases.llvm.org/download.html#4.0.0), e.g. `x86_64-linux-gnu-ubuntu-16.10` for Ubuntu 16.10.
-
-You can also set `LLVM_DOWNLOAD_URL` to a custom url, to download a specific version or from a mirror.
-
 If you don't have `llvm-config`, you need to pass the locations explictly.
 For that set the option `LLVM_VERSION_EXPLICIT` to the version you're using,
 `LIBCLANG_LIBRARY` to the location of the libclang library file,

external/external.cmake

@@ -9,7 +9,7 @@ include(FetchContent)
 find_package(type_safe QUIET)
 if(NOT type_safe_FOUND)
     message(STATUS "Fetching type_safe")
-    FetchContent_Declare(type_safe GIT_REPOSITORY https://github.com/foonathan/type_safe GIT_TAG origin/main)
+    FetchContent_Declare(type_safe GIT_REPOSITORY https://github.com/foonathan/type_safe GIT_TAG 292e8c127037e33d92f8f52dab0f1184993942d0)  # main as of 2026-05-20
     FetchContent_MakeAvailable(type_safe)
 endif()
 
@@ -31,7 +31,7 @@ if(build_tool)
     set(CXXOPTS_BUILD_TESTS OFF CACHE BOOL "")
 
     message(STATUS "Fetching cxxopts")
-    FetchContent_Declare(cxxopts URL https://github.com/jarro2783/cxxopts/archive/v2.2.1.zip)
+    FetchContent_Declare(cxxopts GIT_REPOSITORY https://github.com/jarro2783/cxxopts GIT_TAG a3a21b31ef2894b5a802f041f40d51059469a259)  # master as of 2026-05-20
     FetchContent_MakeAvailable(cxxopts)
 endif()
 
@@ -50,38 +50,6 @@ function(name_without_extension FILENAME NAME)
     set(${NAME} "${name_we}" PARENT_SCOPE)
 endfunction()
 
-# downloads and extracts LLVM using the given URL, filename, and extension
-# sets: LLVM_DOWNLOAD_DIR
-function(_cppast_download_llvm url)
-    get_filename_component(file "${url}" NAME)
-    name_without_extension(${file} folder)
-
-    if(NOT EXISTS ${CMAKE_CURRENT_BINARY_DIR}/${folder})
-        message(STATUS "Downloading LLVM from ${url}")
-        file(DOWNLOAD ${url} ${CMAKE_CURRENT_BINARY_DIR}/${file}
-            STATUS status
-            LOG log)
-
-        list(GET status 0 status_code)
-        list(GET status 1 status_string)
-        if(NOT status_code EQUAL 0)
-            message(FATAL_ERROR "error downloading llvm: ${status_string}" "${log}")
-        endif()
-
-        execute_process(COMMAND ${CMAKE_COMMAND} -E tar xJf ${file}
-                        WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
-    endif()
-
-    set(LLVM_DOWNLOAD_DIR ${CMAKE_CURRENT_BINARY_DIR}/${folder} PARENT_SCOPE)
-endfunction()
-
-# downloads and extracts LLVM using the given version and OS name
-# sets: LLVM_DOWNLOAD_DIR
-function(_cppast_download_llvm_from_llvm_releases version os)
-    _cppast_download_llvm("http://releases.llvm.org/${version}/clang+llvm-${version}-${os}.tar.xz")
-    set(LLVM_DOWNLOAD_DIR ${LLVM_DOWNLOAD_DIR} PARENT_SCOPE)
-endfunction()
-
 # determines the llvm version from a config binary
 macro(_cppast_llvm_version output_name llvm_binary)
     execute_process(COMMAND ${llvm_binary} --version
@@ -94,34 +62,16 @@ endmacro()
 # finds the llvm-config binary
 # sets: LLVM_CONFIG_BINARY
 function(_cppast_find_llvm_config)
-    unset(LLVM_CONFIG_BINARY CACHE)
-    if(LLVM_DOWNLOAD_DIR)
-        find_program(LLVM_CONFIG_BINARY "llvm-config" "${LLVM_DOWNLOAD_DIR}/bin" NO_DEFAULT_PATH)
-    else()
-        find_program(llvm_config_binary_no_suffix llvm-config)
-        find_program(llvm_config_binary_suffix NAMES llvm-config-10 llvm-config-9 llvm-config-8 llvm-config-7 llvm-config-6.0 llvm-config-5.0 llvm-config-4.0)
+    if(NOT LLVM_CONFIG_BINARY)
+
+        find_program(LLVM_CONFIG_BINARY llvm-config)
 
-        if(NOT llvm_config_binary_no_suffix)
-            set(LLVM_CONFIG_BINARY ${llvm_config_binary_suffix} CACHE INTERNAL "")
-        elseif(NOT llvm_config_binary_suffix)
-            set(LLVM_CONFIG_BINARY ${llvm_config_binary_no_suffix} CACHE INTERNAL "")
+        if(NOT LLVM_CONFIG_BINARY)
+            message(FATAL_ERROR "Unable to find llvm-config binary, please set option LLVM_CONFIG_BINARY yourself")
         else()
-            # pick latest version of the two
-            _cppast_llvm_version(suffix_version ${llvm_config_binary_suffix})
-            _cppast_llvm_version(no_suffix_version ${llvm_config_binary_no_suffix})
-            if(suffix_version VERSION_GREATER no_suffix_version)
-                set(LLVM_CONFIG_BINARY ${llvm_config_binary_suffix} CACHE INTERNAL "")
-            else()
-                set(LLVM_CONFIG_BINARY ${llvm_config_binary_no_suffix} CACHE INTERNAL "")
-            endif()
+            message(STATUS "Found llvm-config at ${LLVM_CONFIG_BINARY}")
         endif()
     endif()
-
-    if(NOT LLVM_CONFIG_BINARY)
-        message(FATAL_ERROR "Unable to find llvm-config binary, please set option LLVM_CONFIG_BINARY yourself")
-    else()
-        message(STATUS "Found llvm-config at ${LLVM_CONFIG_BINARY}")
-    endif()
 endfunction()
 
 # find libclang using the config tool
@@ -202,11 +152,7 @@ function(_cppast_find_libclang config_tool min_version force)
     endif()
 endfunction()
 
-set(llvm_min_version 4.0.0)
-
-if(NOT DEFINED LLVM_PREFERRED_VERSION)
-    set(LLVM_PREFERRED_VERSION 4.0.0 CACHE STRING "the preferred LLVM version")
-endif()
+set(llvm_min_version 15.0.0)
 
 if(DEFINED LLVM_VERSION_EXPLICIT)
     if(LLVM_VERSION_EXPLICIT VERSION_LESS llvm_min_version)
@@ -215,11 +161,6 @@ if(DEFINED LLVM_VERSION_EXPLICIT)
     set(LLVM_VERSION ${LLVM_VERSION_EXPLICIT} CACHE INTERNAL "")
     message(STATUS "Using manually specified LLVM version ${LLVM_VERSION}")
 elseif(NOT LLVM_CONFIG_BINARY)
-    if(DEFINED LLVM_DOWNLOAD_OS_NAME)
-        _cppast_download_llvm_from_llvm_releases(${LLVM_PREFERRED_VERSION} ${LLVM_DOWNLOAD_OS_NAME})
-    elseif(DEFINED LLVM_DOWNLOAD_URL)
-        _cppast_download_llvm(${LLVM_DOWNLOAD_URL})
-    endif()
     _cppast_find_llvm_config()
     _cppast_find_libclang(${LLVM_CONFIG_BINARY} ${llvm_min_version} 1) # override here
 else()

external/tpl/CMakeLists.txt

@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.1)
+cmake_minimum_required(VERSION 4.0)
 
 project(tiny-process-library)
 

include/cppast/compile_config.hpp

@@ -168,6 +168,11 @@ class compile_config
         return do_use_c();
     }
 
+    void add_flag(std::string flag)
+    {
+        flags_.push_back(std::move(flag));
+    }
+
 protected:
     compile_config(std::vector<std::string> def_flags) : flags_(std::move(def_flags)) {}
 
@@ -176,11 +181,6 @@ class compile_config
 
     ~compile_config() noexcept = default;
 
-    void add_flag(std::string flag)
-    {
-        flags_.push_back(std::move(flag));
-    }
-
     const std::vector<std::string>& get_flags() const noexcept
     {
         return flags_;

include/cppast/cpp_entity_index.hpp

@@ -46,7 +46,7 @@ struct cpp_entity_id : type_safe::strong_typedef<cpp_entity_id, detail::hash_typ
 inline namespace literals
 {
     /// \returns A new [cppast::cpp_entity_id]() created from the given string.
-    inline cpp_entity_id operator"" _id(const char* str, std::size_t)
+    inline cpp_entity_id operator""_id(const char* str, std::size_t)
     {
         return cpp_entity_id(str);
     }