diff --git a/ChangeLog b/ChangeLog
index 630ddf5880..fde3e3353d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sat May 18 16:57:58 2013  Tanaka Akira  <akr@fsij.org>
+
+	* ext/socket/mkconstants.rb (INTEGER2VALUE): Suppress a warning:
+	  comparison between signed and unsigned integer expressions
+
 Sat May 18 16:38:39 2013  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* compile.c (iseq_compile_each): forward anonymous and first keyword
diff --git a/ext/socket/mkconstants.rb b/ext/socket/mkconstants.rb
index 521aa95547..1f4184f3bd 100644
--- a/ext/socket/mkconstants.rb
+++ b/ext/socket/mkconstants.rb
@@ -282,11 +282,11 @@ result = ERB.new(<<'EOS', nil, '%').result(binding)
 #ifdef HAVE_LONG_LONG
 #define INTEGER2VALUE(n) (0 < (n) ? \
     ((n) <= FIXNUM_MAX ? LONG2FIX(n) : ULL2NUM(n)) : \
-    (FIXNUM_MIN <= (n) ? LONG2FIX(n) : LL2NUM(n)))
+    (FIXNUM_MIN <= (LONG_LONG)(n) ? LONG2FIX(n) : LL2NUM(n)))
 #else
 #define INTEGER2VALUE(n) (0 < (n) ? \
     ((n) <= FIXNUM_MAX ? LONG2FIX(n) : ULONG2NUM(n)) : \
-    (FIXNUM_MIN <= (n) ? LONG2FIX(n) : LONG2NUM(n)))
+    (FIXNUM_MIN <= (long)(n) ? LONG2FIX(n) : LONG2NUM(n)))
 #endif
 
 static void