Set the OpenMP project MacOS Mojave in CLion - c++

Question

I'm trying to execute my homework in C++ with OpenMP on Mac with macOS Mojave. But it's failed. The Mac is new, so all setups are not changed. What I did:
I installed Homebrew.
I installed llvm (brew install llvm)
I installed omp (brew install libomp)
Also, in CMakeLists.txt of the project I have
cmake_minimum_required(VERSION 3.5.1)
project(...)
include_directories("/usr/local/include" "/usr/local/opt/llvm/include")
link_directories("/usr/local/lib" "/usr/local/opt/llvm/lib")
set(CMAKE_CXX_COMPILER /usr/local/opt/llvm/bin/clang++)
set(CMAKE_CXX_STANDARD 14)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -march=native -fopenmp -O3")
add_executable(...)
In Terminal 'clang -v':
Apple LLVM version 10.0.1 (clang-1001.0.46.4)
Target: x86_64-apple-darwin18.6.0
Thread model: posix
InstalledDir: /Library/Developer/CommandLineTools/usr/bin
'gcc -v':
Configured with: --prefix=/Library/Developer/CommandLineTools/usr --with-gxx-include-dir=/Library/Developer/CommandLineTools/SDKs/MacOSX10.14.sdk/usr/include/c++/4.2.1
Apple LLVM version 10.0.1 (clang-1001.0.46.4)
Target: x86_64-apple-darwin18.6.0
Thread model: posix
InstalledDir: /Library/Developer/CommandLineTools/usr/bin
In CLion I have this error:
[ 25%] Linking CXX executable search
ld: unknown option: -platform_version
clang-10: error: linker command failed with exit code 1 (use -v to see invocation)
make[3]: *** [search] Error 1
make[2]: *** [CMakeFiles/search.dir/all] Error 2
make[1]: *** [CMakeFiles/search.dir/rule] Error 2
make: *** [search] Error 2
I re-read a lot of forums, but I still don’t understand what the problem may be.

Answer 1

Be sure to call the Xcode preprocessor to handle OMP.
C++ flags should include:
-Xpreprocessor -fopenmp -lomp -I/usr/local/include
LDFLAGS should include:
-lomp
With cmake you may add them to your command:
cmake -DCMAKE_CXX_FLAGS="-Xpreprocessor -fopenmp -lomp -I/usr/local/include" -DCMAKE_EXE_LINKER_FLAGS="-lomp" ..
or you may add them to your CMakeLists.txt

Answer 2

After trying so many options from the following links
How to set up basic openMP project in CLion
How to set linker flags for OpenMP in CMake's try_compile function
.. and some more
I had the error The CMAKE_CXX_COMPILER: g++-6 is not a full path and was not found in the PATH.
So
i installed GNU gcc from brew instead of Clang (gcc#12 was installed)
brew install gcc
Changed the c++ and c compilers in Preferences > Build, Execution and Development > Toolchains in CLion to the installed compilers in 1
/usr/local/bin/gcc-12 // c
/usr/local/bin/g++-12 // c++
My CMakeList.txt file at this point looks like this:
cmake_minimum_required(VERSION 3.17)
project(test)
set(CMAKE_CXX_STANDARD 11)
add_executable(test main.cpp)
target_compile_options(test PRIVATE -Wall ${OpenMP_CXX_FLAGS})
target_link_libraries(test PRIVATE ${OpenMP_CXX_FLAGS})
and it worked for me.