http://bugs.gentoo.org/378273

--- src/libged/png.c
+++ src/libged/png.c
@@ -30,6 +30,8 @@
 #include <string.h>
 #include "bio.h"
 
+#include <zlib.h> /* Z_BEST_COMPRESSION */
+
 #include "png.h"
 #include "bu.h"
 #include "vmath.h"
--- src/fb/fb-png.c	2011-04-12 14:31:56.000000000 -0400
+++ src/fb/fb-png.c.new	2011-09-19 13:18:08.000000000 -0400
@@ -38,13 +38,13 @@
 #  include <unistd.h>
 #endif
 
+#include "zlib.h"
 #include "png.h"
 #include "bu.h"
 #include "fb.h"
 
 #include "pkg.h"
 
-
 /* in cmap-crunch.c */
 extern void cmap_crunch(RGBpixel (*scan_buf), int pixel_ct, ColorMap *colormap);
 
--- src/util/pix-png.c	2011-04-12 14:34:24.000000000 -0400
+++ src/util/pix-png.c.new	2011-09-19 13:18:59.000000000 -0400
@@ -36,7 +36,8 @@
 #include "bio.h"
 
 #include "zlib.h"
-#include "pngconf.h"
+/* removed as png.h includes this and including it in the wrong order seems to cause bugs
+#include "pngconf.h" */
 #include "png.h"
 
 #include "bu.h"