I have built the MPI binaries many times without issue... until now. I have two machines with the same Ubuntu build, openmpi, and site.settings file on them. The build goes fine on one, but fails on the other (I did the openmpi installation tests and they succeed).
In the build output I see: "'MPI' has not been declared". Below is more of the output... thank you very much in advance for your time!
src/protocols/mpi_refinement/MPI_Refine_Master.cc: In member function 'virtual void protocols::mpi_refinement::MPI_Refine_Master::init()':
src/protocols/mpi_refinement/MPI_Refine_Master.cc:204:15: error: 'MPI' has not been declared
int ncores = MPI::COMM_WORLD.Get_size();
scons: *** [build/src/release/linux/4.4/64/x86/gcc/5.4/mpi/protocols/mpi_refinement/MPI_Refine_Master.os] Error 1
scons: building terminated because of errors."