From: meissner@suse.de
Subject: supply format arguments to gzprintf().

Index: zlib.h
===================================================================
--- zlib.h.orig
+++ zlib.h
@@ -1463,7 +1463,11 @@ ZEXTERN z_size_t ZEXPORT gzfwrite OF((vo
    is returned, and the error state is set to Z_STREAM_ERROR.
 */
 
-ZEXTERN int ZEXPORTVA gzprintf Z_ARG((gzFile file, const char *format, ...));
+ZEXTERN int ZEXPORTVA gzprintf Z_ARG((gzFile file, const char *format, ...))
+#ifdef __GNUC__
+	__attribute__((__format__(__printf__,2,3)))
+#endif
+;
 /*
      Converts, formats, and writes the arguments to the compressed file under
    control of the format string, as in fprintf.  gzprintf returns the number of