From 2ddecfffc3d3a3a1db4ae45e8665caa2a85ab43a Mon Sep 17 00:00:00 2001 From: Ankit Meel Date: Mon, 26 Oct 2020 15:02:20 +0530 Subject: [PATCH] Fix T81077 id_management test on macOS This looks like a optimizer bug where it makes wrong assumptions. The code inside lib_id_delete:264 on rBafd13710b897cc1c11b `for (id = last_remapped_id->next; id; id = id->next) {..}` is not executed in release/relwithdebinfo builds. This can be "fixed" by several ways: - Adding a line that prints the `last_remapped_id->name` right before the said for-loop starts. - Turning off optimization for the whole function `id_delete`: `#pragma clang optimize off/on` Ray Molenkamp - Marking `last_remapped_id` volatile. Julian Eisel - Marking `tagged_deleted_ids` volatile. But it adds a warning when calling `BLI_addtail`: discards volatile qualifier. Discovered by accident. Fix T81077 Reviewed By: mont29 Maniphest Tasks: T81077 Differential Revision: https://developer.blender.org/D9315 --- source/blender/blenkernel/intern/lib_id_delete.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/source/blender/blenkernel/intern/lib_id_delete.c b/source/blender/blenkernel/intern/lib_id_delete.c index 1e45a3c1163..25c48479ef9 100644 --- a/source/blender/blenkernel/intern/lib_id_delete.c +++ b/source/blender/blenkernel/intern/lib_id_delete.c @@ -261,7 +261,9 @@ static void id_delete(Main *bmain, const bool do_tagged_deletion) bool keep_looping = true; while (keep_looping) { ID *id, *id_next; - ID *last_remapped_id = tagged_deleted_ids.last; + /* Marked volatile to avoid a macOS Clang optimization bug. See T81077. + * #last_remapped_id.next is assumed to be NULL by optimizer which is wrong. */ + volatile ID *last_remapped_id = tagged_deleted_ids.last; keep_looping = false; /* First tag and remove from Main all datablocks directly from target lib.