title: How to build boost with mpi support on homebrew?
body: <p>According to this post (<a href="https://github.com/mxcl/homebrew/pull/2953" rel="noreferrer">https://github.com/mxcl/homebrew/pull/2953</a>), the flag "<code>--with-mpi</code>" should enable boost_mpi build support for the related homebrew formula, so I am trying to install boost via homebrew like this:</p>
  
  <pre><code>brew install boost --with-mpi
  </code></pre>
  
  <p>However, the actual boost mpi library is not being build and can not be found.
  There is currently some work being done around this, according to: <a href="https://github.com/mxcl/homebrew/pull/15689" rel="noreferrer">https://github.com/mxcl/homebrew/pull/15689</a></p>
  
  <p>In summary, I can currently build boost, but it seems the "<code>--with-mpi</code>" flag is being ignored. Could someone please check, if I should be able to build boost (with mpi support) on Mac OS X Mountain Lion (10.8)?</p>
  
  <p>The (verbose) output generates these lines:</p>
  
  <pre><code>MPI auto-detection failed: unknown wrapper compiler mpic++
  Please report this error to the Boost mailing list: http://www.boost.org
  You will need to manually configure MPI support.
  
  warning: skipping optional Message Passing Interface (MPI) library.
  note: to enable MPI support, add "using mpi ;" to user-config.jam.
  note: to suppress this message, pass "--without-mpi" to bjam.
  note: otherwise, you can safely ignore this message.
  </code></pre>
  
  <p>Not sure how exactly I can fix this and get the mpi stuff to be build - any ideas?</p>