diff --git a/sys/kern/kern_kse.c b/sys/kern/kern_kse.c
index 1371e7d05e6..4a3e92e8a39 100644
--- a/sys/kern/kern_kse.c
+++ b/sys/kern/kern_kse.c
@@ -1221,7 +1221,7 @@ thread_exit(void)
 	}
 	/* XXX Shouldn't cpu_throw() here. */
 	mtx_assert(&sched_lock, MA_OWNED);
-#if defined(__i386__) || defined(__sparc64__)
+#if defined(__i386__) || defined(__sparc64__) || defined(__amd64__)
 	cpu_throw(td, choosethread());
 #else
 	cpu_throw();
diff --git a/sys/kern/kern_synch.c b/sys/kern/kern_synch.c
index 9d19f13e083..fa3e420babe 100644
--- a/sys/kern/kern_synch.c
+++ b/sys/kern/kern_synch.c
@@ -457,7 +457,7 @@ mi_switch(void)
 {
 	struct bintime new_switchtime;
 	struct thread *td;
-#if defined(__i386__) || defined(__sparc64__)
+#if defined(__i386__) || defined(__sparc64__) || defined(__amd64__)
 	struct thread *newtd;
 #endif
 	struct proc *p;
@@ -517,7 +517,7 @@ mi_switch(void)
 		thread_switchout(td);
 	sched_switchout(td);
 
-#if defined(__i386__) || defined(__sparc64__)
+#if defined(__i386__) || defined(__sparc64__) || defined(__amd64__)
 	newtd = choosethread();
 	if (td != newtd)
 		cpu_switch(td, newtd);	/* SHAZAM!! */
diff --git a/sys/kern/kern_thr.c b/sys/kern/kern_thr.c
index 488cf6f320d..72cc75ccfca 100644
--- a/sys/kern/kern_thr.c
+++ b/sys/kern/kern_thr.c
@@ -111,7 +111,7 @@ thr_exit1(void)
 	sched_exit_thread(TAILQ_NEXT(td, td_kglist), td);
 	thread_stash(td);
 
-#if defined(__i386__) || defined(__sparc64__)
+#if defined(__i386__) || defined(__sparc64__) || defined(__amd64__)
 	cpu_throw(td, choosethread());
 #else
 	cpu_throw();
diff --git a/sys/kern/kern_thread.c b/sys/kern/kern_thread.c
index 1371e7d05e6..4a3e92e8a39 100644
--- a/sys/kern/kern_thread.c
+++ b/sys/kern/kern_thread.c
@@ -1221,7 +1221,7 @@ thread_exit(void)
 	}
 	/* XXX Shouldn't cpu_throw() here. */
 	mtx_assert(&sched_lock, MA_OWNED);
-#if defined(__i386__) || defined(__sparc64__)
+#if defined(__i386__) || defined(__sparc64__) || defined(__amd64__)
 	cpu_throw(td, choosethread());
 #else
 	cpu_throw();
diff --git a/sys/sys/proc.h b/sys/sys/proc.h
index b75c7bab4b2..3027f7bfed2 100644
--- a/sys/sys/proc.h
+++ b/sys/sys/proc.h
@@ -875,7 +875,7 @@ int	sigonstack(size_t sp);
 void	sleepinit(void);
 void	stopevent(struct proc *, u_int, u_int);
 void	cpu_idle(void);
-#if defined(__i386__) || defined(__sparc64__)
+#if defined(__i386__) || defined(__sparc64__) || defined(__amd64__)
 void	cpu_switch(struct thread *old, struct thread *new);
 void	cpu_throw(struct thread *old, struct thread *new) __dead2;
 #else