On 3/15/13 1:19 PM, Hubert Ritzdorf wrote:

Hi,

I'm still developing MPI and I'm also implementing the mpi_f08 module. My concern in connection with BIND(C) are the routines which use character strings (for example MPI_Error_string()).. My Intel compiler aborts the compilation for these functions with

A character dummy argument with length other than 1 is not interoperable

Right. gfortran does the same. In the interface at 349:14-19, the BIND(C) is not compatible with specifying a LEN for the character argument greater than 1. I am not using BIND(C) in the Fortran wrapper definitions. I'm using 349:14-19 as printed except with the BIND(C) deleted. In the corresponding interface block for the actual C function in the library, the declaration is a character(1) array string(*). Here are the texts: Interface for C function (from 349:13) interface !--> MPI_Error_string ! int MPI_Error_string (int errorcode, char *string, int *resultlen); function MPI_Error_string_C (errorcode, string, resultlen) & BIND(C, name="MPI_Error_string") RESULT (res) import :: c_int, c_char integer(c_int),value,intent(in) :: errorcode character(kind=c_char),intent(out) :: string(*) integer(c_int),intent(out) :: resultlen integer(c_int) :: res end function MPI_Error_string_C end interface Fortran wrapper: !--> MPI_Error_string subroutine MPI_Error_string (errorcode, string, resultlen, ierror) use :: mpi_C_interfaces_nobuf, only: c_char, MPI_Error_string_C INTEGER, INTENT(IN) :: errorcode CHARACTER(LEN=MPI_MAX_ERROR_STRING), INTENT(OUT) :: string INTEGER, INTENT(OUT) :: resultlen INTEGER, OPTIONAL, INTENT(OUT) :: ierror integer(c_int) :: errorcode_c integer(c_int) :: resultlen_C integer(c_int) :: res errorcode_c = errorcode res = MPI_Error_string_C (errorcode_c, string, resultlen_c) resultlen = resultlen_c if (present(ierror)) ierror = res end subroutine MPI_Error_string This seems to work - at least it compiles with no errors with 2 different compilers.

I think, that this is correct (but I possibly missed some info on future changes in TSxxxxx). (Nick mentioned in a previous e-mail: "(C) Default CHARACTER is supported only if KIND(' ') is equal to C_CHAR. However, that will almost certainly be the case." I don't know whether this statement fits to the error message above. But almost was true also for the LOGICAL case). Or is this another class of routines which don't support BIND(C) ?

What's about future developments in C and Fortran ?

The Fortran committee operates under the assumption that it cannot require (or even influence) changes in the C standard. The list of C types for which interoperability is supported is fairly limited. There is an assumption that the C standard will not change the meanings of these types, but if they do, and Fortran chooses to be compatible with that new C standard, then the changes would be in Fortran. Fortran 2008 specifies C99 as the C standard for purposes of the interoperability feature. For the TS, everything that is not native to C (the include file and specified functions) all have to be supplied by the Fortran vendor. Cheers, Bill

May they generate new problems for BIND(C) or less problems (i.e. is there a coordinated standardization effort between Fortran and C in order to reduce the interoperability problems) ?

Hubert

-- Bill Long [email protected] Fortran Technical Support & voice: 651-605-9024 Bioinformatics Software Development fax: 651-605-9142 Cray Inc./Cray Plaza, Suite 210/380 Jackson St./St. Paul, MN 55101