Trinity install error

[Jkdubblu]

I am getting an error while installing trinity. This is the code that follows at the end.

IRKE.cpp: In member function ‘void IRKE:opulate_Kmers_from_kmers(const string&)’:
IRKE.cpp:89:62: error: ‘omp_set_num_threads’ was not declared in this scope
omp_set_num_threads(IRKE_COMMON::MAX_THREADS_READ_PARSING); // place limit here because performance deteriorates beyond this value.
^
IRKE.cpp: In member function ‘void IRKE::compute_sequence_assemblies(KmerCounter&, float, unsigned int, unsigned int, bool, bool, std::string)’:
IRKE.cpp:461:53: error: ‘omp_set_num_threads’ was not declared in this scope
omp_set_num_threads(IRKE_COMMON::NUM_THREADS);
^
IRKE.cpp:464:30: error: ‘omp_set_num_threads’ was not declared in this scope
omp_set_num_threads(1); // turn off multithreading for the contig building.
^
make[2]: *** [IRKE.o] Error 1
make[2]: Leaving directory `/panfs/pan.fsl.byu.edu/scr/grp/fslg_phylo640/kyle/software/trinityrnaseq-Trinity-v2.4.0/Inchworm/src'
make[1]: *** [install-recursive] Error 1
make[1]: Leaving directory `/panfs/pan.fsl.byu.edu/scr/grp/fslg_phylo640/kyle/software/trinityrnaseq-Trinity-v2.4.0/Inchworm'
make: *** [inchworm_target] Error 2

Any ideas?