Fortran 90 is the current international Fortran standard. MPI-2 Fortran bindings are Fortran 90 bindings that in most cases are ``Fortran 77 friendly.'' That is, with few exceptions (e.g., KIND-parameterized types, and the mpi module, both of which can be avoided) Fortran 77 compilers should be able to compile MPI programs.
Fortran 90 contains numerous features designed to make it a more
``modern'' language than Fortran 77. It seems natural that MPI
should be able to take advantage of these new features with a set of
bindings tailored to Fortran 90. MPI does not (yet)
use many of these features
because of a number of technical difficulties.
( End of rationale.)
MPI defines two levels of Fortran support, described in Sections Basic Fortran Support and Extended Fortran Support . A third level of Fortran support is envisioned, but is deferred to future standardization efforts. In the rest of this section, ``Fortran'' shall refer to Fortran 90 (or its successor) unless qualified.