diff --git a/ChangeLog b/ChangeLog
index 7c0b93dedd..e0f5d5c861 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Thu Sep 18 06:41:18 2014  Eric Wong  <e@80x24.org>
+
+	* ext/zlib/zlib.c (struct gzfile): pack (288 => 272 bytes) on 64-bit
+
 Thu Sep 18 05:44:05 2014  Eric Wong  <e@80x24.org>
 
 	* ext/socket/init.c (rsock_connect): refactor for blocking
diff --git a/ext/zlib/zlib.c b/ext/zlib/zlib.c
index af45b6f884..23d561f60f 100644
--- a/ext/zlib/zlib.c
+++ b/ext/zlib/zlib.c
@@ -2197,18 +2197,18 @@ struct gzfile {
     struct zstream z;
     VALUE io;
     int level;
-    time_t mtime;       /* for header */
     int os_code;        /* for header */
+    time_t mtime;       /* for header */
     VALUE orig_name;    /* for header; must be a String */
     VALUE comment;      /* for header; must be a String */
     unsigned long crc;
+    int ecflags;
     int lineno;
     long ungetc;
     void (*end)(struct gzfile *);
     rb_encoding *enc;
     rb_encoding *enc2;
     rb_econv_t *ec;
-    int ecflags;
     VALUE ecopts;
     char *cbuf;
     VALUE path;