How do I designate which compiler is called when running cmake + make?

Question

I'm trying to compile a c++ project with cmake and make on OSX but it looks like make is using CXX or clang when I want to use g++ (gcc) so I can follow the answer here to tell the compiler where to find header files (#includes) for tbb used in the project: Need help getting intel TBB working?

brew list shows that I have up to date versions of cmake, make, gcc, and swig installed.

Here's the project I'm trying to compile for reference: https://github.com/nmoehrle/mvs-texturing/blob/master/README.md

Maybe you are looking for CMAKE_CXX_COMPILER and CMAKE_C_COMPILER? — Ilya S, May 05 '20 at 12:48
Clang and GCC have the same syntax regarding compiler flags. There should be no difference — Thomas Sablik, May 05 '20 at 13:04
Do you have [Intel TBB](https://software.intel.com/en-us/tbb) installed? — rustyx, May 05 '20 at 13:32

score 0 · Answer 1 · answered Jun 01 '20 at 16:26

I came across this related answer and was able to get the project working! MacOS, CMake and OpenMP

I updated the cmakelists.txt with the following commands to set llvm as the compiler. Note, I needed to update the llvm file path to match the version number I have installed.

set(CMAKE_C_COMPILER "/usr/local/Cellar/llvm/5.0.1/bin/clang")
set(CMAKE_CXX_COMPILER "/usr/local/Cellar/llvm/5.0.1/bin/clang++")
set(OPENMP_LIBRARIES "/usr/local/Cellar/llvm/5.0.1/lib")
set(OPENMP_INCLUDES "/usr/local/Cellar/llvm/5.0.1/include")

Then I was also having issues with OpenMP so I added this section to configure the OpenMP include directories and link directories.

if (OPENMP_FOUND)
    include_directories("${OPENMP_INCLUDES}")
    link_directories("${OPENMP_LIBRARIES}")
    set (CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${OpenMP_C_FLAGS}")
    set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${OpenMP_CXX_FLAGS}")
endif(OPENMP_FOUND)

I'm a novice dev and wish I had more insight into why this worked but it fixed my issues!

How do I designate which compiler is called when running cmake + make?

1 Answers1