From f054f11a38f66af17a0aed8e0d2d46731eaab27d Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=E5=8D=9C=E9=83=A8=E6=98=8C=E5=B9=B3?= Date: Tue, 17 Dec 2019 15:49:41 +0900 Subject: per-method serial number Methods and their definitions can be allocated/deallocated on-the-fly. One pathological situation is when a method is deallocated then another one is allocated immediately after that. Address of those old/new method entries/definitions can be the same then, depending on underlying malloc/free implementation. So pointer comparison is insufficient. We have to check the contents. To do so we introduce def->method_serial, which is an integer unique to that specific method definition. PS: Note that method_serial being uintptr_t rather than rb_serial_t is intentional. This is because rb_serial_t can be bigger than a pointer on a 32bit system (rb_serial_t is at least 64bit). In order to preserve old packing of struct rb_call_cache, rb_serial_t is inappropriate. --- vm_method.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'vm_method.c') diff --git a/vm_method.c b/vm_method.c index d2bd677e6a..4504468789 100644 --- a/vm_method.c +++ b/vm_method.c @@ -351,6 +351,8 @@ rb_method_definition_create(rb_method_type_t type, ID mid) def = ZALLOC(rb_method_definition_t); def->type = type; def->original_id = mid; + static uintptr_t method_serial = 1; + def->method_serial = method_serial++; return def; } -- cgit v1.2.3