On Thu, 26 Mar 2020, Jakub Jelinek wrote:
> Hi!
>
> The following testcase FAILs since recently when the C++ FE started calling
> protected_set_expr_location more often.
> With -g, it is called on a STATEMENT_LIST that contains a DEBUG_BEGIN_STMT
> and CLEANUP_POINT_EXPR, and as STATEMENT_LISTs have !CAN_HAVE_LOCATION_P,
> nothing is set. Without -g, it is called instead on the CLEANUP_POINT_EXPR
> directly and changes its location.
>
> The following patch recurses on the single non-DEBUG_BEGIN_STMT statement
> of a STATEMENT_LIST if any to make the two behave the same.
>
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
Ick. I fear we really need a better way of dealing with this
STATEMENT_LIST appearance with only -g ...
But OK for now.
Richard.
> 2020-03-26 Jakub Jelinek <ja...@redhat.com>
>
> PR debug/94323
> * tree.c (protected_set_expr_location): Recurse on STATEMENT_LIST
> that contains exactly one non-DEBUG_BEGIN_STMT statement.
>
> * g++.dg/debug/pr94323.C: New test.
>
> --- gcc/tree.c.jj 2020-03-23 19:46:45.552448327 +0100
> +++ gcc/tree.c 2020-03-25 17:22:12.438904778 +0100
> @@ -5146,6 +5146,33 @@ protected_set_expr_location (tree t, loc
> {
> if (CAN_HAVE_LOCATION_P (t))
> SET_EXPR_LOCATION (t, loc);
> + else if (t && TREE_CODE (t) == STATEMENT_LIST)
> + {
> + /* With -gstatement-frontiers we could have a STATEMENT_LIST with
> + DEBUG_BEGIN_STMT(s) and only a single other stmt, which with
> + -g wouldn't be present and we'd have that single other stmt
> + directly instead. */
> + struct tree_statement_list_node *n = STATEMENT_LIST_HEAD (t);
> + if (!n)
> + return;
> + while (TREE_CODE (n->stmt) == DEBUG_BEGIN_STMT)
> + {
> + n = n->next;
> + if (!n)
> + return;
> + }
> + tree t2 = n->stmt;
> + do
> + {
> + n = n->next;
> + if (!n)
> + {
> + protected_set_expr_location (t2, loc);
> + return;
> + }
> + }
> + while (TREE_CODE (n->stmt) == DEBUG_BEGIN_STMT);
> + }
> }
>
> /* Data used when collecting DECLs and TYPEs for language data removal. */
> --- gcc/testsuite/g++.dg/debug/pr94323.C.jj 2020-03-25 17:17:49.857819078
> +0100
> +++ gcc/testsuite/g++.dg/debug/pr94323.C 2020-03-25 17:17:17.533300951
> +0100
> @@ -0,0 +1,13 @@
> +// PR debug/94323
> +// { dg-do compile }
> +// { dg-options "-O2 -fcompare-debug" }
> +
> +volatile int a;
> +
> +void
> +foo ()
> +{
> + ({
> + a;
> + });
> +}
>
> Jakub
>
>
--
Richard Biener <rguent...@suse.de>
SUSE Software Solutions Germany GmbH, Maxfeldstrasse 5, 90409 Nuernberg,
Germany; GF: Felix Imendörffer; HRB 36809 (AG Nuernberg)
