[Bug fortran/46020] New: Improve error string for BIND(C) diagnostic for len>1 character return type

[burnus at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46020

           Summary: Improve error string for BIND(C) diagnostic for len>1
                    character return type
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Keywords: diagnostic
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: bur...@gcc.gnu.org


The following is a misleading error message. The return type may be a character
string -- but only of length one!


FUNCTION F_X(A) bind(c,name='F_X')
1
Error: Return type of BIND(C) function 'f_x' at (1) cannot be a character
string

Example (taken from:
http://groups.google.com/group/comp.lang.fortran/browse_thread/thread/ee444a5894644f72#)

FUNCTION F_X(A) bind(c,name='F_X')
   CHARACTER*(*) F_X
END FUNCTION


NAG prints:
  Error: BIND(C) function F_X has assumed CHARACTER length
though the error for "CHARACTER(len=4)" is also not that helpful:
  Error: BIND(C) function F_X has CHARACTER(LEN=4)


Maybe one can keep the current string and only add "with length > 1", i.e.

Error: Return type of BIND(C) function 'f_x' at (1) cannot be a character
string with length > 1