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From: "anlauf at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug fortran/105012] [12/13 Regression] wrf from SPECCPU2017 ICEs
 during LTO linking since r12-7692-g8db155ddf8cec9
Date: Thu, 25 Aug 2022 21:31:03 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D105012

--- Comment #29 from anlauf at gcc dot gnu.org ---
(In reply to Mikael Morin from comment #28)
> With the following, I get the expected result.
> Indeed, with se->want_pointer set, gfc_conv_expr generates an address
> expression, so it has to be dereferenced to get back the variable.
>=20
> diff --git a/gcc/fortran/trans-expr.cc b/gcc/fortran/trans-expr.cc
> index 6c8fa16e723..367ecc2eb65 100644
> --- a/gcc/fortran/trans-expr.cc
> +++ b/gcc/fortran/trans-expr.cc
> @@ -9602,7 +9602,7 @@ gfc_conv_expr_reference (gfc_se * se, gfc_expr * ex=
pr,
> bool add_clobber)
>           tree var;
>           /* FIXME: This fails if var is passed by reference, see PR
>              41453.  */
> -         var =3D expr->symtree->n.sym->backend_decl;
> +         var =3D build_fold_indirect_ref_loc (input_location, se->expr);
>           clobber =3D build_clobber (TREE_TYPE (var));
>           gfc_add_modify (&se->pre, var, clobber);
>         }

I tried the more hackish

@@ -9529,9 +9540,12 @@ gfc_conv_expr_reference (gfc_se * se, gfc_expr * exp=
r,
bool add_clobber)
        {
          tree clobber;
          tree var;
+         gfc_symbol *sym =3D expr->symtree->n.sym;
          /* FIXME: This fails if var is passed by reference, see PR
             41453.  */
          var =3D expr->symtree->n.sym->backend_decl;
+         if (sym->attr.function && sym->result =3D=3D sym)
+           var =3D gfc_get_fake_result_decl (sym, 0);
          clobber =3D build_clobber (TREE_TYPE (var));
          gfc_add_modify (&se->pre, var, clobber);
        }

but if your patch regtests fine then you should proceed.=