1 files changed, 0 insertions, 1 deletions
diff --git a/vm_core.h b/vm_core.h
index 024b2ce68c..68f246521c 100644
--- a/vm_core.h
+++ b/vm_core.h
@@ -436,7 +436,6 @@ typedef struct rb_thread_struct {
     struct rb_unblock_callback unblock;
     VALUE locking_mutex;
     struct rb_mutex_struct *keeping_mutexes;
-    volatile int transition_for_lock;
 
     struct rb_vm_tag *tag;
     struct rb_vm_protect_tag *protect_tag;