message: Switch MPI_CXX_BOOL to MPI_C_BOOL for AppVeyor
diff: @@ -51,7 +51,7 @@ void ParLinearForm::Assemble(bool use_device)
  {
  bool supports_device = SupportsDevice();
  MPI_Allreduce(&supports_device, &all_supports_device, 1,
  - MPI_CXX_BOOL, MPI_LAND, pfes->GetComm());
  + MPI_C_BOOL, MPI_LAND, pfes->GetComm());
  }
  LinearForm::Assemble(all_supports_device);
  