On Jul 16, 2008, at 11:24 AM, William Gropp wrote:

One piece of relevant text in MPI 2.0 is in section 4.12.6 (in MPI-2.0) says that "All predefined datatypes can be used in datatype constructors in any language." However, the example uses MPI_Type_f2c ton convert the Fortran handle to the C version before passing it into the MPI_Type_create_struct routine, so this text could be interpreted as allowing the use of those datatypes through the handle conversion mechanism without requiring them to be defined in each languages header file. Presumably the requirement is that they be predefined with the value that you'd get from the handle conversion function?

The text in Annex B is stronger than that, though. It specifically states "they are therefore defined for all three language bindings" -- is that a mistake?

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2. Section 3.2.2 on page 27, Section 16.1.6 on page 453, and Annex A.1 on page 491. MPI_LONG_LONG_INT, MPI_LONG_LONG (as synonym), MPI_UNSIGNED_LONG_LONG, MPI_SIGNED_CHAR, and MPI_WCHAR are moved from optional to official and they are therefore defined for all three language bindings.

-- Jeff Squyres Cisco Systems