Not attached are two config.log files. They were too big. They are instead in my Dropbox Public folder: https://dl.dropboxusercontent.com/u/58983082/mpich-intel-badgcc-config.log https://dl.dropboxusercontent.com/u/58983082/mpich-intel-okgcc-config.log One corresponds to an MPICH configure with my default environment and the other with a vanilla environment not including my GCC 4.8.1 install. When the environment knows about GCC 4.8.1, configure tests related to C++ fail. How does MPICH sniff out this non-standard GCC install when I'm using Intel and how do I fix it? Or is the Intel compiler doing this on its own and there's nothing MPICH can do about it? If the latter, does anyone know how to force the Intel compiler to ignore my non-standard GCC install? Thanks, Jeff -- Jeff Hammond [email protected]