Revision control
++ # Copyright (C) 2022 The Qt Company Ltd.
++ # SPDX-License-Identifier: BSD-3-Clause
++
++ # We can't create the same interface imported target multiple times, CMake will complain if we do
++ # that. This can happen if the find_package call is done in multiple different subdirectories.
++ if(TARGET WrapAtomic::WrapAtomic)
++ set(WrapAtomic_FOUND ON)
++ return()
++ endif()
++
++ include(CheckCXXSourceCompiles)
++
++ set (atomic_test_sources "#include <atomic>
++ #include <cstdint>
++
++ int main(int, char **)
++ {
++ volatile std::atomic<char> size_1;
++ volatile std::atomic<short> size_2;
++ volatile std::atomic<int> size_4;
++ volatile std::atomic<int64_t> size_8;
++
++ ++size_1;
++ ++size_2;
++ ++size_4;
++ ++size_8;
++
++ (void)size_1.load(std::memory_order_relaxed);
++ (void)size_2.load(std::memory_order_relaxed);
++ (void)size_4.load(std::memory_order_relaxed);
++ (void)size_8.load(std::memory_order_relaxed);
++
++ return 0;
++ }")
++
++ check_cxx_source_compiles("${atomic_test_sources}" HAVE_STDATOMIC)
++ if(NOT HAVE_STDATOMIC)
++ set(_req_libraries "${CMAKE_REQUIRED_LIBRARIES}")
++ set(atomic_LIB "-latomic")
++ set(CMAKE_REQUIRED_LIBRARIES ${atomic_LIB})
++ check_cxx_source_compiles("${atomic_test_sources}" HAVE_STDATOMIC_WITH_LIB)
++ set(CMAKE_REQUIRED_LIBRARIES "${_req_libraries}")
++ endif()
++
++ add_library(WrapAtomic::WrapAtomic INTERFACE IMPORTED)
++ if(HAVE_STDATOMIC_WITH_LIB)
++ # atomic_LIB is already found above.
++ target_link_libraries(WrapAtomic::WrapAtomic INTERFACE ${atomic_LIB})
++ endif()
++
++ set(WrapAtomic_FOUND 1)
++
++ include(FindPackageHandleStandardArgs)
++ find_package_handle_standard_args(WrapAtomic DEFAULT_MSG WrapAtomic_FOUND)