How can I install openMP on my new MacBook Pro (with Mac OS Catalina)?

Question

I installed Xcode (and also the command line tools) but terminal says (when I\'m compiling):

gcc -o task -fopenmp task.c
clang: error: unsupported option \'-         


        

Answer 1

This https://iscinumpy.gitlab.io/post/omp-on-high-sierra/ suggest to do the following:

brew install libomp

To install the OpenMP runtime components/libraries.

Then, when compiling:

• use -Xpreprocessor -fopenmp in place of -fopenmp in the compile step (-c option)
• add -lomp to the linking step

Note that the above page also mention that CMake 3.12 or later will automatically find the right way of adding OpenMP on MacOS:

cmake_minimum_required(VERSION 3.12)
project(openmptest CXX)

add_executable(sample sample.cpp)

find_package(OpenMP REQUIRED)
target_link_libraries(sample PRIVATE OpenMP::OpenMP_CXX)

Note: I didn't test any of this but it sounds relatively sane