[Bf-blender-cvs] [c7a50d84b63] master: Fix T62684: Crash transforming w/ snap enabled

[Campbell Barton]

Commit: c7a50d84b63f6701305b59151d2a34be95e79205
Author: Campbell Barton
Date:   Mon Mar 18 13:42:53 2019 +1100
Branches: master
https://developer.blender.org/rBc7a50d84b63f6701305b59151d2a34be95e79205

Fix T62684: Crash transforming w/ snap enabled

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

M	source/blender/editors/transform/transform_snap_object.c

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

diff --git a/source/blender/editors/transform/transform_snap_object.c b/source/blender/editors/transform/transform_snap_object.c
index beb420fd498..62ecfdbc59d 100644
--- a/source/blender/editors/transform/transform_snap_object.c
+++ b/source/blender/editors/transform/transform_snap_object.c
@@ -1220,6 +1220,7 @@ static short snap_mesh_polygon(
 		l_iter = l_first = BM_FACE_FIRST_LOOP(f);
 		if (snapdata->snap_to_flag & SCE_SNAP_MODE_EDGE) {
 			elem = SCE_SNAP_MODE_EDGE;
+			BM_mesh_elem_index_ensure(em->bm, BM_EDGE);
 			BM_mesh_elem_table_ensure(em->bm, BM_VERT | BM_EDGE);
 			do {
 				cb_snap_edge(
@@ -1231,6 +1232,7 @@ static short snap_mesh_polygon(
 		}
 		else {
 			elem = SCE_SNAP_MODE_VERTEX;
+			BM_mesh_elem_index_ensure(em->bm, BM_VERT);
 			BM_mesh_elem_table_ensure(em->bm, BM_VERT);
 			do {
 				cb_snap_vert(