Jeff Squyres jsquyres at cisco.com
Fri Feb 4 13:18:08 CST 2011

Question about MPI_UNDEFINED (and all the constants in the top table in MPI-2.2 p515): its type in C is listed as (const int) or unnamed (enum).  But in Open MPI, we have this value in mpi.h as:

    #define MPI_UNDEFINED          -32766

So does MPICH2.

A #define of an integer constant will work just fine with other const int's, but it technically isn't a const int or unnamed enum.

Are we wrong?  Or should I propose a ticket to change the wording of this table from:

    C type: const int (or unnamed enum) 


    C type: const int, unnamed enum, or integer constant

(the same issue doesn't exist for the C++ constants -- even though the point is moot with them, since they're deprecated -- because they're in the MPI:: namespace, and therefore really should be const int's or unnamed enum's)

Jeff Squyres
jsquyres at cisco.com
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