diff --git a/source/blender/editors/mesh/mesh_data.c b/source/blender/editors/mesh/mesh_data.c
index 236e0a35f4e..662470fb97b 100644
--- a/source/blender/editors/mesh/mesh_data.c
+++ b/source/blender/editors/mesh/mesh_data.c
@@ -1038,7 +1038,25 @@ void MESH_OT_customdata_custom_splitnormals_clear(wmOperatorType *ot)
 void ED_mesh_update(Mesh *mesh, bContext *C, bool calc_edges, bool calc_edges_loose)
 {
   if (calc_edges || ((mesh->totpoly || mesh->totface) && mesh->totedge == 0)) {
+    printf("begin: verts: %d, edges: %d, polys: %d, loops: %d\n",
+           mesh->totvert,
+           mesh->totedge,
+           mesh->totpoly,
+           mesh->totloop);
+    for (int i = 0; i < mesh->totedge; i++) {
+      printf("(%d, %d), ", mesh->medge[i].v1, mesh->medge[i].v2);
+    }
+    printf("\n");
     BKE_mesh_calc_edges(mesh, calc_edges, true);
+    printf("end:   verts: %d, edges: %d, polys: %d, loops: %d\n",
+           mesh->totvert,
+           mesh->totedge,
+           mesh->totpoly,
+           mesh->totloop);
+    for (int i = 0; i < mesh->totedge; i++) {
+      printf("(%d, %d), ", mesh->medge[i].v1, mesh->medge[i].v2);
+    }
+    printf("\n");
   }
 
   if (calc_edges_loose && mesh->totedge) {