| function (_cmake_cxx_find_modules_json) |
| if (CMAKE_CXX_STANDARD_LIBRARY STREQUAL "libc++") |
| set(_clang_modules_json_impl "libc++") |
| elseif (CMAKE_CXX_STANDARD_LIBRARY STREQUAL "libstdc++") |
| set(_clang_modules_json_impl "libstdc++") |
| else () |
| set(CMAKE_CXX_COMPILER_IMPORT_STD_ERROR_MESSAGE "Only `libc++` and `libstdc++` are supported" PARENT_SCOPE) |
| return () |
| endif () |
| |
| if (NOT DEFINED CMAKE_CXX_STDLIB_MODULES_JSON) |
| execute_process( |
| COMMAND |
| "${CMAKE_CXX_COMPILER}" |
| ${CMAKE_CXX_COMPILER_ID_ARG1} |
| "-print-file-name=${_clang_modules_json_impl}.modules.json" |
| OUTPUT_VARIABLE _clang_libcxx_modules_json_file |
| ERROR_VARIABLE _clang_libcxx_modules_json_file_err |
| RESULT_VARIABLE _clang_libcxx_modules_json_file_res |
| OUTPUT_STRIP_TRAILING_WHITESPACE |
| ERROR_STRIP_TRAILING_WHITESPACE) |
| if (_clang_libcxx_modules_json_file_res) |
| set(CMAKE_CXX_COMPILER_IMPORT_STD_ERROR_MESSAGE "Could not find `${_clang_modules_json_impl}.modules.json` resource" PARENT_SCOPE) |
| return () |
| endif () |
| set(CMAKE_CXX_STDLIB_MODULES_JSON "${_clang_libcxx_modules_json_file}" PARENT_SCOPE) |
| endif () |
| |
| if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS "18.1.2" AND |
| CMAKE_CXX_STANDARD_LIBRARY STREQUAL "libc++") |
| # The original PR had a key spelling mismatch internally. Do not support it |
| # and instead require a release known to have the fix. |
| # https://github.com/llvm/llvm-project/pull/83036 |
| set(CMAKE_CXX_COMPILER_IMPORT_STD_ERROR_MESSAGE "LLVM 18.1.2 is required for `${_clang_modules_json_impl}.modules.json` format fix" PARENT_SCOPE) |
| return () |
| endif () |
| endfunction () |
