The following code has an ambiguous interface, sub_a and sub_b are identical.
This is correctly reported as an error, if sub_a/sub_b are the only procedures
listed. Adding a third and different overload to the interface (sub_c), the
ambiguity in sub_a/sub_b goes undetected.
$> cat iface.f90
MODULE mod
INTERFACE iface
MODULE PROCEDURE sub_a
MODULE PROCEDURE sub_b
MODULE PROCEDURE sub_c
END INTERFACE
CONTAINS
SUBROUTINE sub_a(x)
INTEGER, INTENT(in) :: x
WRITE (*,*) 'A: ', x
END SUBROUTINE
SUBROUTINE sub_b(y)
INTEGER, INTENT(in) :: y
WRITE (*,*) 'B: ', y
END SUBROUTINE
SUBROUTINE sub_c(x, y)
REAL, INTENT(in) :: x, y
WRITE(*,*) x, y
END SUBROUTINE
END MODULE
PROGRAM test_interface
USE mod
CALL iface(42)
END PROGRAM
$> gfortran-svn -g -Wall iface.f90 && ./a.out
B: 42
$> gfortran-svn -v
Using built-in specs.
Target: i686-pc-linux-gnu
Configured with: ../../svn/gcc/configure --prefix=$(localpath) --disable-nls
--enable-threads=posix --enable-shared --enable-bootstrap --with-system-zlib
--program-suffix=-svn --enable-languages=c,c++,fortran
Thread model: posix
gcc version 4.3.0 20061030 (experimental)
--
Summary: ambiguous interface declaration undetected
Product: gcc
Version: 4.3.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: franke dot daniel at gmail dot com
GCC host triplet: i686-pc-linux-gnu
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29652
