calgray/cmake-cpp-modules-template

Template project for C++20 module support in CMake

CMake C++20 Modules Template

Template project for C++20 module support in CMake. For more information see https://www.kitware.com/import-cmake-c20-modules/.

Features

• Conan support and profiles
• Modularized library targets for common libraries
• Sample unit tests

Libraries

Library	Import Name	CMake Target
std	stdcxx	stdcxx
fmt	fmt.core	fmt-modules
range-v3	range_v3	range-v3-modules
cppcoro	cppcoro	cppcoro-modules
Eigen	eigen	eigen-modules
Cuda	cuda	cuda-modules
boost-ex-ut	boost.ut	boost-ext-ut-modules

(module name std is reserved for C++23 standard)

Requirements

Build tools:

• cmake>=3.26
• ninja>=1.11.0
• conan~=1.60.0

and one of:

• clang>=16.0.0
• msvc>=16.0
• gcc>=13.0.0 (experimental)

Setup with Ninja + Clang

Build

mkdir -p build/clang
conan install . -g cmake_multi -if build/clang -s build_type=Debug --build=missing --profile=profile-clang.txt
conan install . -g cmake_multi -if build/clang -s build_type=Release --build=missing --profile=profile-clang.txt
cmake -B build/clang -G "Ninja Multi-Config" -DCMAKE_CXX_COMPILER=/opt/clang/16.0.0/bin/clang++ -DCONAN_COMPILER=clang -DCONAN_COMPILER_VERSION=16
cmake --build build/clang --config Release -j8

Test

ctest --test-dir build/clang -C Release --output-on-failure

Setup with Ninja + GCC (Experimental)

Build

mkdir -p build/gcc
conan install . -g cmake_multi -if build/gcc -s build_type=Debug --build=missing --profile=profile-gcc.txt
conan install . -g cmake_multi -if build/gcc -s build_type=Release --build=missing --profile=profile-gcc.txt
cmake -B build/gcc -G "Ninja Multi-Config"

Test

ctest --test-dir build/gcc -C Release --output-on-failure

Notes

GCC not fully supported due to not recognizing using alias re-exports. Header unit modules are often prefered by gcc tutorials.

Clang supports either:

• Clang 16 std library (-stdlib=libc++) which can ONLY be exported via a std module. Use profile-clang.txt
• GNU std library (-stdlib=libstdc++) Using profile-stdclang.txt