diff --git a/arch/x86/include/asm/proto.h b/arch/x86/include/asm/proto.h
index b6a9d51d1d79..8c5d1910a848 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);