https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69241
--- Comment #20 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Ah, as for whether versioning supports changing return type to void, clearly it
supports it and even fnsplit uses it for the !split_part_return_p.
So perhaps:
--- ipa-split.c.jj1 2016-01-04 14:55:52.000000000 +0100
+++ ipa-split.c 2016-02-03 13:01:45.905136051 +0100
@@ -1254,7 +1254,7 @@ split_function (basic_block return_bb, s
else
main_part_return_p = true;
}
- /* The main part also returns if we we split on a fallthru edge
+ /* The main part also returns if we split on a fallthru edge
and the split part returns. */
if (split_part_return_p)
FOR_EACH_EDGE (e, ei, split_point->entry_bb->preds)
@@ -1364,8 +1364,9 @@ split_function (basic_block return_bb, s
/* Now create the actual clone. */
cgraph_edge::rebuild_edges ();
node = cur_node->create_version_clone_with_body
- (vNULL, NULL, args_to_skip, !split_part_return_p, split_point->split_bbs,
- split_point->entry_bb, "part");
+ (vNULL, NULL, args_to_skip,
+ !split_part_return_p || !split_point->split_part_set_retval,
+ split_point->split_bbs, split_point->entry_bb, "part");
node->split_part = true;
(completely untested, but fixes the testcase). And as incremental step there
could be what I spoke above, handle SSA uses of DECL_BY_REFERENCE RESULT_DECL
as artificial "parameter".
