[Bf-blender-cvs] [12792ee70cd] master: Fix T83788: Topology mirror crashes for vertices aren't mirrored

[Campbell Barton]

Commit: 12792ee70cd87ce4495a62cb89fd37b95be11917
Author: Campbell Barton
Date:   Tue Dec 15 18:07:12 2020 +1100
Branches: master
https://developer.blender.org/rB12792ee70cd87ce4495a62cb89fd37b95be11917

Fix T83788: Topology mirror crashes for vertices aren't mirrored

Caused by da8dc204bd062b2712869cf2709d2530915249b5

===================================================================

M	source/blender/editors/mesh/editmesh_utils.c

===================================================================

diff --git a/source/blender/editors/mesh/editmesh_utils.c b/source/blender/editors/mesh/editmesh_utils.c
index 6467df0e87b..94f386e08d5 100644
--- a/source/blender/editors/mesh/editmesh_utils.c
+++ b/source/blender/editors/mesh/editmesh_utils.c
@@ -1139,8 +1139,10 @@ void EDBM_verts_mirror_cache_begin_ex(BMEditMesh *em,
 
     if (use_topology) {
       v_mirr = cache_mirr_intptr_as_bmvert(mesh_topo_store.index_lookup, i);
-      if (respecthide && BM_elem_flag_test(v_mirr, BM_ELEM_HIDDEN)) {
-        v_mirr = NULL;
+      if (v_mirr != NULL) {
+        if (respecthide && BM_elem_flag_test(v_mirr, BM_ELEM_HIDDEN)) {
+          v_mirr = NULL;
+        }
       }
     }
     else {