I'm using CMake 3.29.2040507 and a clang/libc++ 19.0 build ``` # CMakeLists.txt cmake_minimum_required(VERSION 3.29.20240507-gf2b76d7) set(CMAKE_CXX_STANDARD 23) set(CMAKE_CXX_STANDARD_REQUIRED YES) set(CMAKE_EXPERIMENTAL_CXX_IMPORT_STD "0e5b6991-d74f-4b3d-a41c-cf096e0b2508") set(CMAKE_CXX_MODULE_STD ON) project(example LANGUAGES CXX) add_executable(main main.cpp) ``` ``` # main.cpp import std; int main() { std::println("hi"); } ``` Running CMake like this on these files: ``` $ cmake -G Ninja -S . -B build -DCMAKE_CXX_COMPILER=/usr/bin/clang++ -DCMAKE_CXX_FLAGS=-stdlib=libc++ ``` produces the following error: ``` CMake Error in CMakeLists.txt: The "CXX_MODULE_STD" property on the target "main" requires that the "__CMAKE::CXX23" target exist, but it was not provided by the toolchain. ```