diff --git a/interpret.h b/interpret.h
index 9910ea7..2901f60 100644
--- a/interpret.h
+++ b/interpret.h
@@ -23,7 +23,19 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
  */
 
-
+#define UNFIELD(l, r) \
+{ \
+	/* if was a field, turn it into a var */ \
+	if ((r->flags & FIELD) == 0) { \
+		l = r; \
+	} else if (r->valref == 1) { \
+		r->flags &= ~FIELD; \
+		l = r; \
+	} else { \
+		l = dupnode(r); \
+		DEREF(r); \
+	} \
+}
 int
 r_interpret(INSTRUCTION *code)
 {
@@ -640,7 +652,12 @@ mod:
 			}
 
 			unref(*lhs);
-			*lhs = POP_SCALAR();
+			if (do_old_mem) {
+				*lhs = POP_SCALAR();
+			} else {
+				r = POP_SCALAR();
+				UNFIELD(*lhs, r);
+			}
 
 			/* execute post-assignment routine if any */
 			if (t1->astore != NULL)
@@ -671,17 +688,7 @@ mod:
 					*lhs = r;
 				} else {
 					r = POP_SCALAR();
-
-					/* if was a field, turn it into a var */
-					if ((r->flags & FIELD) == 0) {
-						*lhs = r;
-					} else if (r->valref == 1) {
-						r->flags &= ~FIELD;
-						*lhs = r;
-					} else {
-						*lhs = dupnode(r);
-						DEREF(r);
-					}
+					UNFIELD(*lhs, r);
 				}
 			}
 			break;
@@ -698,7 +705,12 @@ mod:
 			decr_sp();
 			DEREF(t1);
 			unref(*lhs);
-			*lhs = POP_SCALAR();
+			if (do_old_mem) {
+				*lhs = POP_SCALAR();
+			} else {
+				r = POP_SCALAR();
+				UNFIELD(*lhs, r);
+			}
 			assert(assign != NULL);
 			assign();
 		}
@@ -752,8 +764,13 @@ mod:
 			lhs = POP_ADDRESS();
 			r = TOP_SCALAR();
 			unref(*lhs);
-			*lhs = r;
-			UPREF(r);
+			if (do_old_mem) {
+				*lhs = r;
+				UPREF(r);
+			} else {
+				UPREF(r);
+				UNFIELD(*lhs, r);
+			}
 			REPLACE(r);
 			break;