On Mar 2, 2013, at 11:57 AM CST, Jeff Hammond wrote:

...

If you actually had a compiler that would give an _error_ when "long long" was used in C++, then we could skip checking "long long" in that case. So maybe "-Werror=long-long"?

This really is a waste of everyone's time. Just add "-Wno-long-long" and move on to a real problem.

Sure, but it still surprises me that MPI_Count requires a C99 type when at least one member of the MPICH team is quite strict about the need for MPICH to use only C89 features in order to work with the Microsoft C compiler.

MPI_Count does not require C99 types in all cases. It just uses them when the *C* compiler used to build MPICH supports "long long" and the device does not set MPID_NO_LONG_LONG=yes in its "_PREREQ_" m4 macros in subconfigure.m4. The issue is that none of the code is testing whether the C++ compiler supports "long long". It's just not worth actually doing it, since they all support it unless you go out of your way to disable that support with "-Werror=long-long". -Dave