[OMPI users] Suggestion: adding OMPI_ versions macros in mpi.h

[Audet, Martin]

Hi,

I would like to suggest you to add macros indicating the version of the OpenMPI 
library in the C/C++ header file mpi.h analogous to the parameter constants in 
the Fortran header file:

   parameter (OMPI_MAJOR_VERSION=1)
   parameter (OMPI_MINOR_VERSION=1)
   parameter (OMPI_RELEASE_VERSION=4)
   parameter (OMPI_GREEK_VERSION="")
   parameter (OMPI_SVN_VERSION="r13362")

This would be very handy if someone discover a bug XYZ and a workaround for it 
in OpenMPI versions before (and not including) 1.1.4 for example and wants his 
code to be portable on many OpenMPI versions and also on other MPI-2 
implementations. In this situation he could do something like this in a common 
C header file:

   #ifdef OPEN_MPI

   /* true iff (x.y.z < u.v.w) */
   #define DOTTED_LESS_THAN(x,y,z, u,v,w)   \
      (((x) < (u)) || (((x) == (u)) && (((y) < (v)) || (((y) == (v)) && ((z) < 
(w))))))

   # if DOTTED_LESS_THAN(OMPI_MAJOR_VERSION, OMPI_MINOR_VERSION, 
OMPI_RELEASE_VERSION, 1,1,4)
   #  define USE_MPI_WORKAROUND_XYZ
   # endif

   #endif


And later in the C source code:

   #ifdef USE_MPI_WORKAROUND_XYZ
     /* use the workaround */
   #else
     /* use the normal method */
   #endif


Thanks,

Martin