https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77505
--- Comment #9 from Elizebeth Punnoose <elizebethp at gmail dot com> ---
(In reply to Janne Blomqvist from comment #8)
> (In reply to Elizebeth Punnoose from comment #6)
> > Modified code with the warning message moved behind -fcheck=bounds.
> >
> > Index: trans-array.c
> > ===================================================================
> > --- trans-array.c (revision 241960)
> > +++ trans-array.c (working copy)
> > @@ -2226,6 +2226,8 @@
> > gfc_ss_info *ss_info;
> > gfc_expr *expr;
> > gfc_ss *s;
> > + tree neg_len;
> > + char *msg;
> >
> > /* Save the old values for nested checking. */
> > old_first_len = first_len;
> > @@ -2271,6 +2273,27 @@
> > gfc_conv_expr_type (&length_se, expr->ts.u.cl->length,
> > gfc_charlen_type_node);
> > ss_info->string_length = length_se.expr;
> > +
> > + /* Check if the character length is negative,
> > + if so consider it as LEN=0. */
> > + neg_len = fold_build2_loc (input_location, LT_EXPR,
> > + boolean_type_node, ss_info->string_length,
> > + build_int_cst (gfc_charlen_type_node, 0));
> > + /* Print a warning if bounds checking is enabled. */
> > + if (gfc_option.rtcheck & GFC_RTCHECK_BOUNDS)
> > + {
> > + msg = xasprintf ("Negative character length will be treated as
> > LEN=0");
> > + gfc_trans_runtime_check (false, true, neg_len,
> > + &length_se.pre, where, msg);
> > + free(msg);
> > + }
> > + ss_info->string_length = fold_build3_loc (input_location,
> > + COND_EXPR, gfc_charlen_type_node,
> > + neg_len, gfc_index_zero_node,
> > + ss_info->string_length);
> > + ss_info->string_length = gfc_evaluate_now (ss_info->string_length,
> > + &length_se.pre);
> > +
> > gfc_add_block_to_block (&outer_loop->pre, &length_se.pre);
> > gfc_add_block_to_block (&outer_loop->post, &length_se.post);
> > }
>
>
> Shouldn't you have build_int_cst (gfc_charlen_type_node, 0) instead of
> gfc_index_zero_node?
Thank you for your comment. I will make the necessary changes and re-post.
