http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46478
Summary: Missing diagnosis for combining SUBROUTINE and
FUNCTION in a GENERIC interface
Product: gcc
Version: 4.6.0
Status: UNCONFIRMED
Keywords: accepts-invalid
Severity: normal
Priority: P3
Component: fortran
AssignedTo: unassig...@gcc.gnu.org
ReportedBy: bur...@gcc.gnu.org
Found at:
http://groups.google.com/group/comp.lang.fortran/browse_thread/thread/2084596e400fdf2d
gfortran allows generic interfaces which combine FUNCTIONs with SUBROUTINEs.
That's invalid Fortran, but allowed as vendor extension as it is not a
constraint.
gfortran diagnoses the problem if one does not use "(MODULE) PROCEDURE" but
includes the declaration directly in the interface body - albeit the error
message is not very clear:
Error: SUBROUTINE at (1) does not belong in a generic function interface
Other compiles:
- NAG rejects it with
Error: SUBR_NAME and FUNC_NAME must both be SUBROUTINEs or both be FUNCTIONs
for generic NEW_NAME
- g95 with
Error: Interfaces of generic 'new_name' at (1) must all be FUNCTIONs
or SUBROUTINEs
- ifort has a warning -- and only with -stand f03:
warning #7953: Standard Fortran requires that within a scoping unit, two
procedures that have the same generic name shall both be subroutines or both
be functions. [SUBR_NAME]
Even with -std=f95, gfortran does not even issue a warning.
Expected:
- Reject it with -std=f95/f2008
- Consider print a warning by default for -std=gnu; printing an error
would also be possible
MODULE something
INTERFACE new_name
PROCEDURE func_name, subr_name
END INTERFACE
CONTAINS
LOGICAL FUNCTION func_name(arg1,arg2)
! :
END FUNCTION
SUBROUTINE subr_name(arg1,arg2,arg3)
! :
END SUBROUTINE
END MODULE
