diff --git a/arch/x86/include/asm/proto.h b/arch/x86/include/asm/proto.h
index 6e81788a30c1..0eaca7a130c9 100644
--- a/arch/x86/include/asm/proto.h
+++ b/arch/x86/include/asm/proto.h
@@ -4,6 +4,8 @@
 
 #include <asm/ldt.h>
 
+struct task_struct;
+
 /* misc architecture specific prototypes */
 
 void syscall_init(void);