http://bugs.gentoo.org/465504
http://github.com/apitrace/apitrace/issues/118

--- a/image/image_png.cpp
+++ b/image/image_png.cpp
@@ -31,6 +31,7 @@
 #include <assert.h>
 #include <stdint.h>
 #include <stdlib.h>
+#include <string.h>
 
 #include <fstream>