Build issue on Mac OS (omp.h not found)

> [ 10%] Built target lib_CoinUtils

> [ 12%] Built target lib_Osi

> [ 21%] Built target lib_clp

> [ 22%] Built target lib_OsiClpSolver

> [ 23%] Built target openMVG_stlplus

> [ 23%] Built target main_svgSample

> [ 33%] Built target openMVG_cxsparse

> [ 33%] Building CXX object third_party/ceres-solver/internal/ceres/CMakeFiles/openMVG_ceres.dir/block_evaluate_preparer.cc.o

> In file included from /Users/jason/git/openMVG/src/third_party/ceres-solver/internal/ceres/block_evaluate_preparer.cc:34:

> In file included from /Users/jason/git/openMVG/src/third_party/ceres-solver/internal/ceres/block_sparse_matrix.h:38:

> In file included from /Users/jason/git/openMVG/src/third_party/ceres-solver/internal/ceres/sparse_matrix.h:38:

> In file included from /Users/jason/git/openMVG/src/third_party/ceres-solver/include/ceres/internal/eigen.h:34:

> /Users/jason/git/openMVG/src/third_party/eigen/Eigen/Core:70:10: fatal error: 'omp.h' file not found

> #include <omp.h>

>          ^~~~~~~

> 1 error generated.

> make[2]: *** [third_party/ceres-solver/internal/ceres/CMakeFiles/openMVG_ceres.dir/block_evaluate_preparer.cc.o] Error 1

> make[1]: *** [third_party/ceres-solver/internal/ceres/CMakeFiles/openMVG_ceres.dir/all] Error 2

> make: *** [all] Error 2



Various SO posts implied that Apple did something weird with the clang compiler and that some of these built in files no longer come with macOS.



I used `brew install libomp` and updated the files below to directly point to a new omp.h file but that didn't seem to do anything:



- OpenMPCheckVersion.cpp

- OpenMPTryFlag.cpp

- OpenMPCheckVersion.c

- OpenMPTryFlag.c



Let me know if there's anything else I can do to get this working. Will try docker approach in the meantime.

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