* added from https://github.com/rofl0r/sabotage

--- gdb-7.6.orig/gdb/common/linux-ptrace.h	2013-01-01 07:32:54.000000000 +0100
+++ gdb-7.6/gdb/common/linux-ptrace.h	2013-08-13 17:10:13.000000000 +0200
@@ -20,6 +20,7 @@
 
 struct buffer;
 
+#include <unistd.h>
 #include <sys/ptrace.h>
 
 #ifndef PTRACE_GETSIGINFO