diff --git a/ChangeLog b/ChangeLog
index a4b97011831d79..a3bb1ec080c8de 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Thu Jan 20 06:03:17 2011  Tanaka Akira  <akr@fsij.org>
+
+	* method.h: parenthesize macro arguments.
+
 Wed Jan 19 13:16:05 2011  Eric Hodel  <drbrain@segment7.net>
 
 	* lib/rubygems/commands/sources_command.rb: Finish removing code,
diff --git a/method.h b/method.h
index 3cfe438f25eb32..61555b079f4ef0 100644
--- a/method.h
+++ b/method.h
@@ -26,8 +26,8 @@ typedef enum {
 } rb_method_flag_t;
 
 #define NOEX_SAFE(n) ((int)((n) >> 8) & 0x0F)
-#define NOEX_WITH(n, s) ((s << 8) | (n) | (ruby_running ? 0 : NOEX_BASIC))
-#define NOEX_WITH_SAFE(n) NOEX_WITH(n, rb_safe_level())
+#define NOEX_WITH(n, s) (((s) << 8) | (n) | (ruby_running ? 0 : NOEX_BASIC))
+#define NOEX_WITH_SAFE(n) NOEX_WITH((n), rb_safe_level())
 
 /* method data type */