1 files changed, 6 insertions, 1 deletions
diff --git a/source/blender/modifiers/intern/MOD_cast.c b/source/blender/modifiers/intern/MOD_cast.c
index 5f2043d8c09..ef8530557d7 100644
--- a/source/blender/modifiers/intern/MOD_cast.c
+++ b/source/blender/modifiers/intern/MOD_cast.c
@@ -502,10 +502,15 @@ static void deformVertsEM(ModifierData *md,
     mesh_src = MOD_deform_mesh_eval_get(ctx->object, editData, mesh, NULL, numVerts, false, false);
   }
 
-  if (mesh_src) {
+  if (mesh && mesh->runtime.wrapper_type == ME_WRAPPER_TYPE_MDATA) {
     BLI_assert(mesh_src->totvert == numVerts);
   }
 
+  /* TODO(Campbell): use edit-mode data only (remove this line). */
+  if (mesh_src != NULL) {
+    BKE_mesh_wrapper_ensure_mdata(mesh_src);
+  }
+
   if (cmd->type == MOD_CAST_TYPE_CUBOID) {
     cuboid_do(cmd, ctx, ctx->object, mesh_src, vertexCos, numVerts);
   }