3 files changed, 7 insertions, 2 deletions
diff --git a/ChangeLog b/ChangeLog
index 89e0250c17..b34530ef7c 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Tue May 17 20:20:49 2011  KOSAKI Motohiro  <kosaki.motohiro@gmail.com>
+
+	* vm_core.h (rb_thread_struct): add volatile to
+	  transition_for_lock because it is not protected by lock.
+
 Sun May 15 21:22:35 2011  CHIKANAGA Tomoyuki  <nagachika00@gmail.com>
 
 	* cont.c (cont_init): clear macihne_stack_start/end of saved thread to
diff --git a/version.h b/version.h
index 1968722c60..a2433451da 100644
--- a/version.h
+++ b/version.h
@@ -1,5 +1,5 @@
 #define RUBY_VERSION "1.9.2"
-#define RUBY_PATCHLEVEL 252
+#define RUBY_PATCHLEVEL 253
 #define RUBY_VERSION_MAJOR 1
 #define RUBY_VERSION_MINOR 9
 #define RUBY_VERSION_TEENY 1
diff --git a/vm_core.h b/vm_core.h
index 2c73dd7e95..0c2b3f4e52 100644
--- a/vm_core.h
+++ b/vm_core.h
@@ -427,7 +427,7 @@ typedef struct rb_thread_struct
     struct rb_unblock_callback unblock;
     VALUE locking_mutex;
     struct rb_mutex_struct *keeping_mutexes;
-    int transition_for_lock;
+    volatile int transition_for_lock;
 
     struct rb_vm_tag *tag;
     struct rb_vm_protect_tag *protect_tag;