__printflike might not be defined at all :-)

--- src/lib/errors.h.orig	2014-02-17 19:23:32.078758868 +0100
+++ src/lib/errors.h	2014-02-17 19:24:22.046134190 +0100
@@ -55,6 +55,10 @@
 
 #include <errno.h>
 
+#ifndef __printflike
+#define __printflike(n,m)	__attribute__((format(printf,n,m)))
+#endif
+
 /** error codes */
 /* Remember to add names to map in errors.c */
 typedef enum {