diff --git a/.gdbinit b/.gdbinit
index 6481376d48..c4cdd1f0e6 100644
--- a/.gdbinit
+++ b/.gdbinit
@@ -768,3 +768,7 @@ define trace_machine_instructions
   end
 end
 
+define SDR
+  call rb_vmdebug_stack_dump_raw_current()
+end
+
diff --git a/ChangeLog b/ChangeLog
index 058f831a19..46437f1ca6 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Mon Jun 11 05:21:57 2012  Koichi Sasada  <ko1@atdot.net>
+
+	* .gdbinit (SDR): add SDR function.  It's only for VM debugging.
+
 Sun Jun 10 21:50:45 2012  Yuki Sonoda (Yugui)  <yugui@yugui.jp>
 
 	* nacl/nacl_config.rb: Fixed for 32bit hosts.