diff --git a/lib/zlib/inffast.h b/lib/zlib/inffast.h
index e5c1aa4..49c6d15 100644
--- a/lib/zlib/inffast.h
+++ b/lib/zlib/inffast.h
@@ -8,4 +8,4 @@
    subject to change. Applications should only use zlib.h.
  */
 
-void ZLIB_INTERNAL inflate_fast OF((z_streamp strm, unsigned start));
+void ZLIB_INTERNAL inflate_fast(z_streamp strm, unsigned start);