| # Enable scanning by default for targets that explicitly use C++ 20. |
| cmake_policy(SET CMP0155 NEW) |
| |
| # Block making C++ `import std` targets. |
| add_library(__CMAKE::CXX23 IMPORTED INTERFACE) |
| |
| enable_language(CXX) |
| |
| # Hide any real scanning rule that may be available. |
| unset(CMAKE_CXX_SCANDEP_SOURCE) |
| |
| # Explicitly enable C++20 for all targets. |
| set(CMAKE_CXX_STANDARD 20) |
| set(CMAKE_CXX_STANDARD_REQUIRED ON) |
| |
| # Explicitly suppress scanning so that support is not required. |
| set(CMAKE_CXX_SCAN_FOR_MODULES OFF) |
| |
| add_executable(noscanning-variable main-no-use.cxx) |
| |
| # Verify that CMAKE_CXX_SCAN_FOR_MODULES is propagated into the check. |
| # FIXME: Unset CMAKE_CXX_SCANDEP_SOURCE inside try_compile so this |
| # test can verify behavior on newer compilers too. |
| try_compile(result SOURCES ${CMAKE_CURRENT_SOURCE_DIR}/main-no-use.cxx) |
