fix [#36923] Merge / Delete vertices crashes for some meshes

add BM_ITER_MESH_MUTABLE which steps before entering the for() loop body and prevents the assert from complaining about removing mesh data while iterating as well as the crash.

this was done in quite a few areas, more may turn up.

1 files changed, 6 insertions, 6 deletions

diff --git a/source/blender/bmesh/intern/bmesh_construct.c b/source/blender/bmesh/intern/bmesh_construct.c
index 930964667e9..1a7464ce340 100644
--- a/source/blender/bmesh/intern/bmesh_construct.c
+++ b/source/blender/bmesh/intern/bmesh_construct.c
@@ -500,10 +500,10 @@ BMFace *BM_face_create_ngon_vcloud(BMesh *bm, BMVert **vert_arr, int len,
  */
 void BMO_remove_tagged_faces(BMesh *bm, const short oflag)
 {
-	BMFace *f;
+	BMFace *f, *f_next;
 	BMIter iter;
 
-	BM_ITER_MESH (f, &iter, bm, BM_FACES_OF_MESH) {
+	BM_ITER_MESH_MUTABLE (f, f_next, &iter, bm, BM_FACES_OF_MESH) {
 		if (BMO_elem_flag_test(bm, f, oflag)) {
 			BM_face_kill(bm, f);
 		}
@@ -512,10 +512,10 @@ void BMO_remove_tagged_faces(BMesh *bm, const short oflag)
 
 void BMO_remove_tagged_edges(BMesh *bm, const short oflag)
 {
-	BMEdge *e;
+	BMEdge *e, *e_next;
 	BMIter iter;
 
-	BM_ITER_MESH (e, &iter, bm, BM_EDGES_OF_MESH) {
+	BM_ITER_MESH_MUTABLE (e, e_next, &iter, bm, BM_EDGES_OF_MESH) {
 		if (BMO_elem_flag_test(bm, e, oflag)) {
 			BM_edge_kill(bm, e);
 		}
@@ -524,10 +524,10 @@ void BMO_remove_tagged_edges(BMesh *bm, const short oflag)
 
 void BMO_remove_tagged_verts(BMesh *bm, const short oflag)
 {
-	BMVert *v;
+	BMVert *v, *v_next;
 	BMIter iter;
 
-	BM_ITER_MESH (v, &iter, bm, BM_VERTS_OF_MESH) {
+	BM_ITER_MESH_MUTABLE (v, v_next, &iter, bm, BM_VERTS_OF_MESH) {
 		if (BMO_elem_flag_test(bm, v, oflag)) {
 			BM_vert_kill(bm, v);
 		}