diff --git a/ChangeLog b/ChangeLog
index d54b131402..894604fe20 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Mon Apr 14 19:52:35 2008  Akinori MUSHA  <knu@iDaemons.org>
+
+	* ruby.h: New macro: RB_GC_GUARD().
+
 Mon Apr 14 19:49:35 2008  Akinori MUSHA  <knu@iDaemons.org>
 
 	* random.c (rb_genrand_int32, rb_genrand_real), intern.h: Export.
diff --git a/ruby.h b/ruby.h
index abf9e11085..a646c6a690 100644
--- a/ruby.h
+++ b/ruby.h
@@ -224,6 +224,8 @@ VALUE rb_ull2inum _((unsigned LONG_LONG));
 
 #define TYPE(x) rb_type((VALUE)(x))
 
+#define RB_GC_GUARD(v) (*(volatile VALUE *)&(v))
+
 void rb_check_type _((VALUE,int));
 #define Check_Type(v,t) rb_check_type((VALUE)(v),t)