I have a user that wants me to check their F2003 code which uses mpif.h. Attempting to compile with gfortran-4.8.2 -std=f2003 results in errors coming from mpif.h. I tried configuring MPICH (v3.1-16-g38a5e61) using FCFLAGS=-std=f2003, but I get build errors. GFortran does not have a -std=gnu2003, so it appears that GNU extensions and F2003+ features are mutually exclusive. What is MPICH's intent here? mpifnoext.h:16.18: Included at src/binding/f90/mpi_constants.f90:6: CHARACTER*1 MPI_ARGVS_NULL(1,1) 1 Warning: Obsolescent feature: Old-style character length at (1) mpifnoext.h:17.18: Included at src/binding/f90/mpi_constants.f90:6: CHARACTER*1 MPI_ARGV_NULL(1) 1 Warning: Obsolescent feature: Old-style character length at (1) mpifnoext.h:528.16: Included at src/binding/f90/mpi_constants.f90:6: integer*8 MPI_DISPLACEMENT_CURRENT 1 Error: GNU Extension: Nonstandard type declaration INTEGER*8 at (1) mpifnoext.h:529.42: Included at src/binding/f90/mpi_constants.f90:6: PARAMETER (MPI_DISPLACEMENT_CURRENT=-54278278) 1 Error: Symbol 'mpi_displacement_current' at (1) has no IMPLICIT type