https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81245
--- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #4)
> The fix:
> Index: gcc/tree-if-conv.c
> ===================================================================
> --- gcc/tree-if-conv.c (revision 249769)
> +++ gcc/tree-if-conv.c (working copy)
> @@ -1853,8 +1853,8 @@
> new_stmt = gimple_build_assign (res, rhs);
> gsi_insert_before (gsi, new_stmt, GSI_SAME_STMT);
> gimple_stmt_iterator new_gsi = gsi_for_stmt (new_stmt);
> + update_stmt (new_stmt);
> fold_stmt (&new_gsi, ifcvt_follow_ssa_use_edges);
> - update_stmt (new_stmt);
>
> if (dump_file && (dump_flags & TDF_DETAILS))
> {
Actually
if (fold_stmt (...))
update_stmt (gsi_stmt (new_gsi));
is correct ;) The old update_stmt was redundant (gsi_insert_before updates
the stmt already). fold_stmt may replace the stmt so with your fix you
might just end up updating a stale one...
