https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64921
--- Comment #21 from rguenther at suse dot de <rguenther at suse dot de> --- On July 27, 2015 8:45:41 PM GMT+02:00, "mikael at gcc dot gnu.org" <gcc-bugzi...@gcc.gnu.org> wrote: >https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64921 > >Mikael Morin <mikael at gcc dot gnu.org> changed: > > What |Removed |Added >---------------------------------------------------------------------------- > CC| |mikael at gcc dot gnu.org > >--- Comment #20 from Mikael Morin <mikael at gcc dot gnu.org> --- >(In reply to Richard Biener from comment #19) >> So the question is whether the frontend emits the correct test >against zero: >> >> offset = offset * byte_stride; >> D.3466 = (void *) array->data; >> D.3467 = D.3466; >> D.3465 = 8; >> D.3469 = 8; >> __builtin_memcpy ((void *) &transfer.4, (void *) >> &D.3467, (unsigned long) MAX_EXPR <MIN_EXPR <D.3469, D.3465>, 0>); >> ptr2 = (struct t4 *) (transfer.4 + offset); >> if (ptr2 != 0B) >> { >> { >> integer(kind=4) stat.5; >> >> if (ptr2->k == 0B) >> >> to me it looks like if we really want to test transfer.4 >(array->data) >> against >> zero. > >transfer.4 + offset calculates the address of an element of an array. >I believe that if that code is executed, array.data is non-zero, and >of course >array.data + offset as well. Yes but if transfer.4 is null then transfer.4 + offset does not have to be. Transfer.4 _is_ null in the case we segfault. So the guard us clearly wrong. >I think the the test should check for ptr2%j's nullness before >deallocating >ptr2%j, instead of testing ptr2. > >With a patch like this: > >diff --git a/gcc/fortran/class.c b/gcc/fortran/class.c >index 218973d..1ff7437 100644 >--- a/gcc/fortran/class.c >+++ b/gcc/fortran/class.c >@@ -967,7 +967,7 @@ finalize_component (gfc_expr *expr, gfc_symbol >*derived, >gfc_component *comp, > cond->block->expr1->ts.kind = gfc_default_logical_kind; > cond->block->expr1->value.function.isym = gfc_intrinsic_function_by_id >(GFC_ISYM_ASSOCIATED); > cond->block->expr1->value.function.actual = gfc_get_actual_arglist (); >- cond->block->expr1->value.function.actual->expr = gfc_copy_expr >(expr); >+ cond->block->expr1->value.function.actual->expr = gfc_copy_expr >(e); >cond->block->expr1->value.function.actual->next = >gfc_get_actual_arglist >(); > cond->block->next = dealloc; > > >Unfortunately, it doesn't seem to fix the problem.
