| Message ID | 4D3B1C08.2050709@net-b.de |
|---|---|
| State | New |
| Headers | show |
Hi Tobias, > On 01/15/2011 02:45 PM, Thomas Koenig wrote: >>>> here is an update of the patch. This one just warns about array >>>> sections if they are followed by component references. > > s/warns/prints an error/ > >> Revision 169130 übertragen. > > How about the following patch on top of it? I think the crucial part > (for F2008 at least) is rather the contiguity. The patch looks longer > than it is due to white space changes. Shouldn't the test on gfc_is_simply_contiguous be reversed? The test case in c_loc_tests_16.f90 would then have to be changed. Thomas
Hi Tobias, >> > On 01/15/2011 02:45 PM, Thomas Koenig wrote: >>>>> >>>> here is an update of the patch. This one just warns about array >>>>> >>>> sections if they are followed by component references. >> > >> > s/warns/prints an error/ >> > >>> >> Revision 169130 übertragen. >> > >> > How about the following patch on top of it? I think the crucial part >> > (for F2008 at least) is rather the contiguity. The patch looks longer >> > than it is due to white space changes. > Shouldn't the test on gfc_is_simply_contiguous be reversed? The test > case in c_loc_tests_16.f90 would then have to be changed. I applied your patch with the test reversed and tested it with the following source: ig25@linux-fd1f:~/Krempel/Ref-c> cat cloc.f90 ! { dg-do compile } ! PR 38536 - array sections as arguments to c_loc are illegal. program main use iso_c_binding implicit none interface subroutine fun(arg) BIND(C) use iso_c_binding type(c_ptr) :: arg end subroutine fun end interface integer(c_int), target :: n(3) type(C_PTR) :: p n(1) = 3 n(2) = 5 n(3) = 7 p = c_loc(n) call fun(p) p = c_loc(n(2:3)) ! { dg-warning "Array section" } call fun(p) print *,n end program main ig25@linux-fd1f:~/Krempel/Ref-c> cat fun.c #include <stdio.h> void fun(void *); void fun(void *p) { int *pp; pp = p; printf("%p %d %d\n",p, pp[0], pp[1]); } ig25@linux-fd1f:~/Krempel/Ref-c> gfortran cloc.f90 fun.c ig25@linux-fd1f:~/Krempel/Ref-c> ./a.out 0x7fff4e19b508 1310307600 32767 0x7fff4e19b508 1310307604 32767 3 5 7 Either my test program is wrong (which is entirely possible because I don't use ISO C binding myself, much), or there are at least two problems with using c_loc like this - the first version should have worked in any case. Thomas
Dear Thomas, Thomas Koenig wrote: > I applied your patch with the test reversed and tested it with the > following source: > > [...] > interface > subroutine fun(arg) BIND(C) > use iso_c_binding > type(c_ptr) :: arg [...] > void fun(void *); The interface does not really match. On the Fortran side, you have "void **" on the C side you only have "void *". Try: type(c_ptr), VALUE :: arg The result is then: 0x7fffc66564c0 3 5 0x7fffc66564c4 5 7 3 5 7 C Binding is described at http://gcc.gnu.org/onlinedocs/gfortran/Mixed_002dLanguage-Programming.html -- and the pointer handling in particular at http://gcc.gnu.org/onlinedocs/gfortran/Working-with-Pointers.html Side remark: If it were not for a C_LOC example, I had used "int *" on the C side and "integer(c_int) :: arg(*)" on the Fortran side. Tobias
Hi Tobias, > Dear Thomas, > > Thomas Koenig wrote: >> I applied your patch with the test reversed and tested it with the >> following source: >> >> [...] >> interface >> subroutine fun(arg) BIND(C) >> use iso_c_binding >> type(c_ptr) :: arg > [...] >> void fun(void *); > > The interface does not really match. On the Fortran side, you have "void > **" on the C side you only have "void *". You learn something new every day... Your patch is OK with the test for gfc_is_simply_contiguous reversed, regression-testing and an appropriate test case and change to c_loc_tests_16.f90. Thomas
diff --git a/gcc/fortran/resolve.c b/gcc/fortran/resolve.c index 9f0d675..f458cbe 100644 --- a/gcc/fortran/resolve.c +++ b/gcc/fortran/resolve.c @@ -2700,7 +2700,6 @@ gfc_iso_c_func_interface (gfc_symbol *sym, gfc_actual_arglist *args, else if (sym->intmod_sym_id == ISOCBINDING_LOC) { gfc_ref *ref; - bool seen_section; /* Make sure we have either the target or pointer attribute. */ if (!arg_attr.target && !arg_attr.pointer) @@ -2722,35 +2721,29 @@ gfc_iso_c_func_interface (gfc_symbol *sym, gfc_actual_arglist *args, /* Follow references to make sure there are no array sections. */ - seen_section = false; for (ref=args->expr->ref; ref; ref = ref->next) { if (ref->type == REF_ARRAY) - { - if (ref->u.ar.type == AR_SECTION) - seen_section = true; - - if (ref->u.ar.type != AR_ELEMENT) - { - gfc_ref *r; - for (r = ref->next; r; r=r->next) - if (r->type == REF_COMPONENT) - { + if (ref->u.ar.type != AR_ELEMENT) + { + gfc_ref *r; + for (r = ref->next; r; r=r->next) + if (r->type == REF_COMPONENT) + { gfc_error_now ("Array section not permitted" " in '%s' call at %L", name, &(args->expr->where)); retval = FAILURE; break; - } - } - } + } + } } - if (seen_section && retval == SUCCESS) - gfc_warning ("Array section in '%s' call at %L", name, + if (retval == SUCCESS && gfc_is_simply_contiguous (args->expr, false)) + gfc_warning ("Array might be not contiguous in '%s' call at %L", name, &(args->expr->where)); - + /* See if we have interoperable type and type param. */ if (verify_c_interop (arg_ts) == SUCCESS || gfc_check_any_c_kind (arg_ts) == SUCCESS)