From 5a048829a488bb1cb4b0e77b3d46a1920ad92136 Mon Sep 17 00:00:00 2001
From: John Hawthorn <john@hawthorn.email>
Date: Wed, 15 Sep 2021 02:40:42 -0700
Subject: [PATCH] Add WB_PROTECTED to mutexes

mutex_mark is (basically) NULL, so we don't have any references to mark.
This means we should safely be able to mark Mutex as WB_PROTECTED
without changing anything else.
---
 thread_sync.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/thread_sync.c b/thread_sync.c
index ba5a78ca0a..98d95ff009 100644
--- a/thread_sync.c
+++ b/thread_sync.c
@@ -125,7 +125,7 @@ mutex_memsize(const void *ptr)
 static const rb_data_type_t mutex_data_type = {
     "mutex",
     {mutex_mark, mutex_free, mutex_memsize,},
-    0, 0, RUBY_TYPED_FREE_IMMEDIATELY
+    0, 0, RUBY_TYPED_WB_PROTECTED | RUBY_TYPED_FREE_IMMEDIATELY
 };
 
 static rb_mutex_t *