diff --git a/vm_insnhelper.h b/vm_insnhelper.h
index aabbf8387d..1a3dbc0326 100644
--- a/vm_insnhelper.h
+++ b/vm_insnhelper.h
@@ -184,6 +184,7 @@ CC_SET_ME(CALL_CACHE cc, const rb_callable_method_entry_t *me)
 } while (0)
 #endif
 
+#define PREV_CLASS_SERIAL() (ruby_vm_class_serial)
 #define NEXT_CLASS_SERIAL() (++ruby_vm_class_serial)
 #define GET_GLOBAL_METHOD_STATE() (ruby_vm_global_method_state)
 #define INC_GLOBAL_METHOD_STATE() (++ruby_vm_global_method_state)
diff --git a/vm_method.c b/vm_method.c
index 2e948144d6..90ed0ba5f7 100644
--- a/vm_method.c
+++ b/vm_method.c
@@ -104,7 +104,7 @@ rb_clear_method_cache_by_class(VALUE klass)
 	    INC_GLOBAL_METHOD_STATE();
 	}
 	else {
-	    rb_serial_t old_serial = rb_next_class_serial();
+	    rb_serial_t old_serial = PREV_CLASS_SERIAL();
 	    rb_class_clear_method_cache(klass, (VALUE)&old_serial);
 	}
     }