https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109500
--- Comment #19 from Steve Kargl <sgk at troutmask dot apl.washington.edu> ---
On Thu, Apr 20, 2023 at 05:22:59AM +0000, kargl at gcc dot gnu.org wrote:
>
> I think we agree on all points. Here's the diff I envision.
> NOte, I've restricted it to user defined functions. Remove
> the esym check will enable it for any subprogram.
>
>
> diff --git a/gcc/fortran/interface.cc b/gcc/fortran/interface.cc
> index db79b104dc2..f3bcdd76d6a 100644
> --- a/gcc/fortran/interface.cc
> +++ b/gcc/fortran/interface.cc
> @@ -3622,6 +3622,18 @@ gfc_compare_actual_formal (gfc_actual_arglist **ap,
> gfc_formal_arglist *formal,
> goto match;
> }
>
> + if (a->expr->expr_type == EXPR_FUNCTION
> + && a->expr->value.function.esym
> + && f->sym->attr.allocatable)
> + {
> + if (where)
> + gfc_error ("Actual argument for %qs at %L is a function result "
> + "and the dummy argument is ALLOCATABLE",
> + f->sym->name, &a->expr->where);
> + ok = false;
> + goto match;
> + }
> +
> /* Check intent = OUT/INOUT for definable actual argument. */
> if (!in_statement_function
> && (f->sym->attr.intent == INTENT_OUT
>
The patch passes regtesting.
PS: I think what you want to with a runtime check and an undefine
function result is a good idea. I haven't looked to see where
and how hard this might be to implement.
