3 files changed, 7 insertions, 2 deletions
diff --git a/ChangeLog b/ChangeLog
index 9d5c1115e4..61f3de171e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sun Apr  8 06:53:55 2012  NARUSE, Yui  <naruse@ruby-lang.org>
+
+	* io.c (io_unread): cast as long the value for extra_max.
+	  [ruby-core:44137] [Bug #6257]
+
 Sat Apr  7 10:28:40 2012  Aaron Patterson <aaron@tenderlovemaking.com>
 
 	* ext/psych/lib/psych.rb: bumping up psych version to match release.
diff --git a/io.c b/io.c
index 0e17d44ba6..d491267733 100644
--- a/io.c
+++ b/io.c
@@ -290,7 +290,7 @@ inline static int set_binary_mode_with_seek_cur(rb_io_t *fptr) {
 	return setmode(fptr->fd, O_BINARY);
     }
     /* add extra offset for removed '\r' in rbuf */
-    extra_max = pos - fptr->rbuf.len;
+    extra_max = (long)(pos - fptr->rbuf.len);
     p = fptr->rbuf.ptr + fptr->rbuf.off;
     for (i = 0; i < fptr->rbuf.len; i++) {
 	if (*p == '\n') newlines++;
diff --git a/version.h b/version.h
index 0eea88d086..7cdc647e0a 100644
--- a/version.h
+++ b/version.h
@@ -1,5 +1,5 @@
 #define RUBY_VERSION "1.9.3"
-#define RUBY_PATCHLEVEL 177
+#define RUBY_PATCHLEVEL 178
 
 #define RUBY_RELEASE_DATE "2012-04-08"
 #define RUBY_RELEASE_YEAR 2012