--- pngcrush-1.8.11/zutil.h.orig	2017-09-04 09:05:51.391314480 +0200
+++ pngcrush-1.8.11/zutil.h	2017-09-04 09:04:27.037805744 +0200
@@ -30,7 +30,7 @@
 #endif
 
 #ifdef Z_SOLO
-   typedef long ptrdiff_t;  /* guess -- will be caught if guess is wrong */
+/*   typedef long ptrdiff_t;  /* guess -- will be caught if guess is wrong */
 #endif
 
 #ifndef local