Change def->method_serial to be atomic

luke-gruber · jhawthorn · commit 3c66eb335831 · 2025-06-25T15:43:57.000-07:00
`rb_method_definition_create` can be called across different ractors at the same time, so `def-&gt;method_serial` should be atomic.
diff --git a/vm_method.c b/vm_method.c
@@ -879,15 +879,16 @@ method_definition_reset(const rb_method_entry_t *me)
     }
 }
 
+static rb_atomic_t method_serial = 1;
+
 rb_method_definition_t *
 rb_method_definition_create(rb_method_type_t type, ID mid)
 {
     rb_method_definition_t *def;
     def = ZALLOC(rb_method_definition_t);
     def->type = type;
     def->original_id = mid;
-    static uintptr_t method_serial = 1;
-    def->method_serial = method_serial++;
+    def->method_serial = (uintptr_t)RUBY_ATOMIC_FETCH_ADD(method_serial, 1);
     def->ns = rb_current_namespace();
     return def;
 }

Original file line number	Diff line number	Diff line change
`@@ -879,15 +879,16 @@ method_definition_reset(const rb_method_entry_t *me)`
`879`	`879`	`}`
`880`	`880`	`}`
`881`	`881`
	`882`	`+static rb_atomic_t method_serial = 1;`
	`883`	`+`
`882`	`884`	`rb_method_definition_t *`
`883`	`885`	`rb_method_definition_create(rb_method_type_t type, ID mid)`
`884`	`886`	`{`
`885`	`887`	`rb_method_definition_t *def;`
`886`	`888`	`def = ZALLOC(rb_method_definition_t);`
`887`	`889`	`def->type = type;`
`888`	`890`	`def->original_id = mid;`
`889`		`- static uintptr_t method_serial = 1;`
`890`		`- def->method_serial = method_serial++;`
	`891`	`+ def->method_serial = (uintptr_t)RUBY_ATOMIC_FETCH_ADD(method_serial, 1);`
`891`	`892`	`def->ns = rb_current_namespace();`
`892`	`893`	`return def;`
`893`	`894`	`}`