Fix T39331: Dissolve vertex crash

source/blender/bmesh/intern/bmesh_mods.c

@@ -205,6 +205,7 @@ bool BM_disk_dissolve(BMesh *bm, BMVert *v)
 			return false;
 		}
 		
+		if (e->l) {
 			/* get remaining two faces */
 			f = e->l->f;
 			f2 = e->l->radial_next->f;
@@ -216,6 +217,7 @@ bool BM_disk_dissolve(BMesh *bm, BMVert *v)
 				}
 			}
 		}
+	}
 
 	return true;
 }