Not quite sure if this CP2K derived testcase is really a bug, but for the
testcase below, I get the following warning and later an error (this might be
different issues?) :
> gfortran -flto test_c.c test.f90
test_c.c:3:8: warning: type of build_eri does not match original declaration
[enabled by default]
test.f90:3:0: note: previously declared here
> cat test_c.c
#include<stdio.h>
void (*build_eri)();
void foo()
{
printf("foo\n");
};
void init()
{
build_eri=foo;
};
> cat test.f90
MODULE M1
USE ISO_C_BINDING
TYPE(C_FUNPTR), BIND(C) :: build_eri
INTERFACE
SUBROUTINE foo() BIND(C)
END SUBROUTINE foo
END INTERFACE
INTERFACE
SUBROUTINE init() BIND(C)
END SUBROUTINE init
END INTERFACE
CONTAINS
SUBROUTINE test
PROCEDURE(foo), POINTER :: foo_ptr
CALL init()
CALL C_F_PROCPOINTER(build_eri,foo_ptr)
CALL foo_ptr()
END SUBROUTINE
END MODULE
USE M1
CALL test
END
this can now be turned in an error using :
> gcc -c -flto test_c.c
> gfortran -c -flto test.f90
> ar -r all.a test_c.o test.o
> gfortran -fuse-linker-plugin -flto -O3 all.a
/data03/vondele/binutils-2.20.1/build/bin/ld: error: all.a: multiple definition
of 'build_eri'
/data03/vondele/binutils-2.20.1/build/bin/ld: all.a: previous definition here
test.f90:3:0: warning: type of build_eri does not match original declaration
[enabled by default]
test_c.c:3:8: note: previously declared here
collect2: ld returned 1 exit status
--
Summary: LTO / function pointers with iso_c_binding
Product: gcc
Version: 4.6.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: fortran
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: Joost dot VandeVondele at pci dot uzh dot ch
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45659
