make error

[xncaffe]

I compiled your code under ubuntu14.04 system, but there was an error about openmp, I can not solve it myself, asking for your help. Looking forward to your reply. Very grateful!

[xncaffe]

.build_release/lib/libcaffe.so：对‘omp_set_num_threads’未定义的引用
collect2: error: ld returned 1 exit status
.build_release/lib/libcaffe.so：对‘omp_set_num_threads’未定义的引用
make: *** [.build_release/tools/upgrade_solver_proto_text.bin] 错误 1
make: *** 正在等待未完成的任务....
collect2: error: ld returned 1 exit status
make: *** [.build_release/tools/create_label_map.bin] 错误 1
.build_release/lib/libcaffe.so：对‘omp_set_num_threads’未定义的引用
collect2: error: ld returned 1 exit status
make: *** [.build_release/tools/upgrade_net_proto_text.bin] 错误 1
.build_release/lib/libcaffe.so：对‘omp_set_num_threads’未定义的引用
.build_release/lib/libcaffe.so：对‘omp_set_num_threads’未定义的引用
.build_release/lib/libcaffe.so：对‘omp_set_num_threads’未定义的引用
collect2: error: ld returned 1 exit status
make: *** [.build_release/tools/extract_features.bin] 错误 1
collect2: error: ld returned 1 exit status
collect2: error: ld returned 1 exit status
make: *** [.build_release/tools/upgrade_net_proto_binary.bin] 错误 1
make: *** [.build_release/tools/caffe.bin] 错误 1