title: omp.h' file not found while compiling source code
body: <p>I am trying to compile this this source code (<a href="https://sites.google.com/site/bgcsoftware/" rel="nofollow noreferrer">https://sites.google.com/site/bgcsoftware/</a>) on a mac. I installed both hdf5 and gsl using homebrew.</p>
  <p>Would you know what the problem might be?</p>
  <p>Thank you in advance!</p>
  <pre><code>h5c++ -Wall -O2 -o bgc bgc_main.C bgc_func_readdata.C bgc_func_initialize.C bgc_func_mcmc.C bgc_func_write.C bgc_func_linkage.C bgc_func_ngs.C bgc_func_hdf5.C mvrandist.c -lgsl -lm
  </code></pre>
  <pre><code>clang: warning: treating 'c' input as 'c++' when in C++ mode, this behavior is deprecated [-Wdeprecated]
  bgc_main.C:17:10: fatal error: 'omp.h' file not found
  #include &lt;omp.h&gt;
           ^~~~~~~
  1 error generated.
  bgc_func_mcmc.C:12:10: fatal error: 'omp.h' file not found
  #include &lt;omp.h&gt;
           ^~~~~~~
  1 error generated.
  </code></pre>