[Bug fortran/30964] optional arguments to random_seed

["fxcoudert at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #9 from fxcoudert at gcc dot gnu dot org  2007-08-12 00:16 -------
Haven't yet had time to regtest this patch, but it should fix the bug:

Index: trans-expr.c
===================================================================
--- trans-expr.c        (revision 127363)
+++ trans-expr.c        (working copy)
@@ -2303,36 +2303,38 @@ gfc_conv_function_call (gfc_se * se, gfc
            } 
        }

-      if (fsym)
-       {
-         if (e)
+      /* The case with fsym->attr.optional is that of a user subroutine
+        with an interface indicating an optional argument.  When we call
+        an intrinsic subroutine, however, fsym is NULL, but we might still
+        have an optional argument, so we proceed to the substitution
+        just in case.  */
+      if (e && (fsym == NULL || fsym->attr.optional))
+       {
+         /* If an optional argument is itself an optional dummy argument,
+            check its presence and substitute a null if absent.  */
+         if (e->expr_type == EXPR_VARIABLE
+             && e->symtree->n.sym->attr.optional)
+           gfc_conv_missing_dummy (&parmse, e, fsym ? fsym->ts : e->ts);
+       }
+
+      if (fsym && e)
+       {
+         /* Obtain the character length of an assumed character length
+            length procedure from the typespec.  */
+         if (fsym->ts.type == BT_CHARACTER
+             && parmse.string_length == NULL_TREE
+             && e->ts.type == BT_PROCEDURE
+             && e->symtree->n.sym->ts.type == BT_CHARACTER
+             && e->symtree->n.sym->ts.cl->length != NULL)
            {
-             /* If an optional argument is itself an optional dummy
-                argument, check its presence and substitute a null
-                if absent.  */
-             if (e->expr_type == EXPR_VARIABLE
-                   && e->symtree->n.sym->attr.optional
-                   && fsym->attr.optional)
-               gfc_conv_missing_dummy (&parmse, e, fsym->ts);
-
-             /* Obtain the character length of an assumed character
-                length procedure from the typespec.  */
-             if (fsym->ts.type == BT_CHARACTER
-                   && parmse.string_length == NULL_TREE
-                   && e->ts.type == BT_PROCEDURE
-                   && e->symtree->n.sym->ts.type == BT_CHARACTER
-                   && e->symtree->n.sym->ts.cl->length != NULL)
-               {
-                 gfc_conv_const_charlen (e->symtree->n.sym->ts.cl);
-                 parmse.string_length
-                       = e->symtree->n.sym->ts.cl->backend_decl;
-               }
+             gfc_conv_const_charlen (e->symtree->n.sym->ts.cl);
+             parmse.string_length = e->symtree->n.sym->ts.cl->backend_decl;
            }
-
-         if (need_interface_mapping)
-           gfc_add_interface_mapping (&mapping, fsym, &parmse);
        }

+      if (fsym && need_interface_mapping)
+       gfc_add_interface_mapping (&mapping, fsym, &parmse);
+
       gfc_add_block_to_block (&se->pre, &parmse.pre);
       gfc_add_block_to_block (&post, &parmse.post);



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30964