R crashes when using -qopenmp flag

I have an R package available here: https://github.com/jsilve24/mongrel/tree/develop

I have started linking this to MKL using  following R makevars parameters:

PKG_CPPFLAGS =  -I../inst/include/ -DMONGREL_USE_MKL
PKG_CXXFLAGS = -I/opt/intel/compilers_and_libraries_2019.1.144/mac/mkl/include -qopenmp
PKG_LIBS = -L/opt/intel/compilers_and_libraries_2019.1.144/mac/mkl/lib -Wl,-rpath,/opt/intel/compilers_and_libraries_2019.1.144/mac/mkl/lib -lmkl_intel_lp64 -lmkl_intel_thread -lmkl_core -liomp5 -lpthread -lm -ldl 

However whenever I add the -qopenmp flag as I do above everything compiles but R crashes whenever I try to run the program. This never happened when I was using Clang. I am now using  icc (ICC) 19.0.1.144 20181018. 

I don't know where to even begin debugging this problem. I would like to use my own omp pragmas but without that flag I don't believe I can (unless I am mistaken). 

Thank you!

Justin