diff --git a/src/libthread/threadimpl.h b/src/libthread/threadimpl.h
index bc0667f7..507c0764 100644
--- a/src/libthread/threadimpl.h
+++ b/src/libthread/threadimpl.h
@@ -138,6 +138,7 @@ struct Proc
 	Lock		lock;
 	int			nswitch;
 	_Thread		*thread;
+	_Thread		*pinthread;
 	_Threadlist	runqueue;
 	_Threadlist	idlequeue;
 	_Threadlist	allthreads;