Files
dssp/cmake/FindFilesystem.cmake
2021-09-29 13:39:18 +02:00

75 lines
2.2 KiB
CMake

# Simplistic reimplementation of https://github.com/vector-of-bool/CMakeCM/blob/master/modules/FindFilesystem.cmake
if(TARGET std::filesystem)
return()
endif()
cmake_minimum_required(VERSION 3.10)
include(CMakePushCheckState)
include(CheckIncludeFileCXX)
include(CheckCXXSourceCompiles)
cmake_push_check_state()
set(CMAKE_CXX_STANDARD 17)
check_include_file_cxx("filesystem" _CXX_FILESYSTEM_HAVE_HEADER)
mark_as_advanced(_CXX_FILESYSTEM_HAVE_HEADER)
set(code [[
#include <cstdlib>
#include <filesystem>
int main() {
auto cwd = std::filesystem::current_path();
return EXIT_SUCCESS;
}
]])
if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS_EQUAL 8.4.0)
# >> https://stackoverflow.com/questions/63902528/program-crashes-when-filesystempath-is-destroyed
set(CXX_FILESYSTEM_NO_LINK_NEEDED 0)
else()
# Check a simple filesystem program without any linker flags
check_cxx_source_compiles("${code}" CXX_FILESYSTEM_NO_LINK_NEEDED)
endif()
if(CXX_FILESYSTEM_NO_LINK_NEEDED)
set(_found 1)
else()
set(prev_libraries ${CMAKE_REQUIRED_LIBRARIES})
# Add the libstdc++ flag
set(CMAKE_REQUIRED_LIBRARIES ${prev_libraries} -lstdc++fs)
check_cxx_source_compiles("${code}" CXX_FILESYSTEM_STDCPPFS_NEEDED)
set(_found ${CXX_FILESYSTEM_STDCPPFS_NEEDED})
if(NOT CXX_FILESYSTEM_STDCPPFS_NEEDED)
# Try the libc++ flag
set(CMAKE_REQUIRED_LIBRARIES ${prev_libraries} -lc++fs)
check_cxx_source_compiles("${code}" CXX_FILESYSTEM_CPPFS_NEEDED)
set(_found ${CXX_FILESYSTEM_CPPFS_NEEDED})
endif()
endif()
if(_found)
add_library(std::filesystem INTERFACE IMPORTED)
set_property(TARGET std::filesystem APPEND PROPERTY INTERFACE_COMPILE_FEATURES cxx_std_17)
if(CXX_FILESYSTEM_NO_LINK_NEEDED)
# Nothing to add...
elseif(CXX_FILESYSTEM_STDCPPFS_NEEDED)
set_target_properties(std::filesystem PROPERTIES IMPORTED_LIBNAME stdc++fs)
elseif(CXX_FILESYSTEM_CPPFS_NEEDED)
set_target_properties(std::filesystem PROPERTIES IMPORTED_LIBNAME c++fs)
endif()
endif()
cmake_pop_check_state()
set(Filesystem_FOUND ${_found} CACHE BOOL "TRUE if we can run a program using std::filesystem" FORCE)
if(Filesystem_FIND_REQUIRED AND NOT Filesystem_FOUND)
message(FATAL_ERROR "Cannot run simple program using std::filesystem")
endif()