diff --git a/ChangeLog b/ChangeLog
index 47620205a7..e014fcdb58 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Tue Aug 28 22:31:49 2012  CHIKANAGA Tomoyuki  <nagachika@ruby-lang.org>
+
+	* insns.def (checkmatch): suppress warnings. [ruby-core:47339]
+	  [Bug #6930]
+
 Tue Aug 28 20:03:54 2012  NARUSE, Yui  <naruse@ruby-lang.org>
 
 	* configure.in: Fixing Haiku R1/alpha3 build with gcc-4.4.4.
diff --git a/insns.def b/insns.def
index 797e5ec6f5..04ecd8d8c8 100644
--- a/insns.def
+++ b/insns.def
@@ -833,6 +833,8 @@ checkmatch
 (VALUE target, VALUE pattern)
 (VALUE result)
 {
+    enum vm_check_match_type checkmatch_type =
+      (enum vm_check_match_type)(flag & VM_CHECKMATCH_TYPE_MASK);
     result = Qfalse;
 
     if (flag & VM_CHECKMATCH_ARRAY) {
@@ -847,7 +849,7 @@ checkmatch
 	}
     }
     else {
-	if (RTEST(check_match(pattern, target, flag & VM_CHECKMATCH_TYPE_MASK))) {
+	if (RTEST(check_match(pattern, target, checkmatch_type))) {
 	    result = Qtrue;
 	}
     }