Layers/Collections: Fix crash when deleting collection

If the collection to be deleted has a nested collection that is directly linked
to a view layer, we were getting a crash.

1 files changed, 9 insertions, 0 deletions

diff --git a/source/blender/blenkernel/intern/collection.c b/source/blender/blenkernel/intern/collection.c
index f6915cc2432..e2b10de575c 100644
--- a/source/blender/blenkernel/intern/collection.c
+++ b/source/blender/blenkernel/intern/collection.c
@@ -188,6 +188,15 @@ bool BKE_collection_remove(ID *owner_id, SceneCollection *sc)
 		return false;
 	}
 
+	/* We need to do bottom up removal, otherwise we get a crash when we remove a collection that
+	 * has one of its nested collections linked to a view layer. */
+	SceneCollection *scene_collection_nested = sc->scene_collections.first;
+	while (scene_collection_nested != NULL) {
+		SceneCollection *scene_collection_next = scene_collection_nested->next;
+		BKE_collection_remove(owner_id, scene_collection_nested);
+		scene_collection_nested = scene_collection_next;
+	}
+
 	/* Unlink from the respective collection tree. */
 	if (!collection_remlink(sc_master, sc)) {
 		BLI_assert(false);