Fix: Crash when using "On Selected Markers" mode for Propogate Pose with no markers present

The function to get a list of markers was not clearing the list before it exited
early, and with no way to tell that the method failed, callers could make the
mistake of trusting that the list was now valid (i.e. either full of marker
frames or empty, vs being invalid)

1 files changed, 13 insertions, 1 deletions

diff --git a/source/blender/editors/animation/anim_markers.c b/source/blender/editors/animation/anim_markers.c
index 140b7e0b117..68660740ac7 100644
--- a/source/blender/editors/animation/anim_markers.c
+++ b/source/blender/editors/animation/anim_markers.c
@@ -266,8 +266,20 @@ void ED_markers_make_cfra_list(ListBase *markers, ListBase *lb, short only_sel)
 {
 	TimeMarker *marker;
 	
-	if (markers == NULL)
+	if (lb) {
+		/* Clear the list first, since callers have no way of knowing
+		 * whether this terminated early otherwise. This may lead
+		 * to crashes if the user didn't clear the memory first.
+		 */
+		lb->first = lb->last = NULL;
+	}
+	else {
+		return;
+	}
+	
+	if (markers == NULL) {
 		return;
+	}
 	
 	for (marker = markers->first; marker; marker = marker->next)
 		add_marker_to_cfra_elem(lb, marker, only_sel);