MPI-4: Missing `MPI_F_XXX` C constants

[dalcinl]

I'm using branch v5.0.x to assess MPI-4 support.

There are 4 trivial constants (C only) that are missing and should be trivial to add (MPI-4, pp. 844, ln. 5):

• MPI_F_STATUS_SIZE
• MPI_F_SOURCE
• MPI_F_TAG
• MPI_F_ERROR

Adding something the following lines to mpi.h should be enough:

#define MPI_F_STATUS_SIZE OMPI_FORTRAN_STATUS_SIZE
#define MPI_F_SOURCE 0
#define MPI_F_TAG 1
#define MPI_F_ERROR 2

[dalcinl]

@awlauria Could you please ad the MPI-4.0 label ?

[jjhursey]

@drwootton said that he would try to get to this next week.

[jjhursey]

PR #10491 has been merged. The changes will be cherry-picked to the v5.0.x, v4.1.x, and v4.0.x branches.

[jjhursey]

For reference, this has been merged into the relevant release branches.

• main: Add Missing MPI_F_XXX C constants #10491
• v5.0.x: v5.0.x: Add Missing MPI_F_XXX C constants #10530
• v4.1.x: v4.1.x: Add Missing MPI_F_XXX C constants #10530  #10534
• v4.0.x: v4.0.x: Add Missing MPI_F_XXX C constants #10530  #10533