diff --git a/sys/i386/include/globals.h b/sys/i386/include/globals.h
index 846cba9c34c7..a20d83bfcf77 100644
--- a/sys/i386/include/globals.h
+++ b/sys/i386/include/globals.h
@@ -135,6 +135,7 @@ extern struct proc *npxproc;
 extern int switchticks;			/* `ticks' at last context switch. */
 extern struct timeval switchtime;	/* Uptime at last context switch. */
 extern struct segment_descriptor *tss_gdt;
+extern int	witness_spin_check;
 
 #endif /* SMP || KLD_MODULE */
 
diff --git a/sys/kern/kern_mutex.c b/sys/kern/kern_mutex.c
index 4e5376632b5f..2d486531a373 100644
--- a/sys/kern/kern_mutex.c
+++ b/sys/kern/kern_mutex.c
@@ -656,10 +656,6 @@ mtx_destroy(struct mtx *m)
 #define WITNESS_COUNT 200
 #define	WITNESS_NCHILDREN 2
 
-#ifndef SMP
-extern int witness_spin_check;
-#endif
-
 int witness_watch = 1;
 
 struct witness {
diff --git a/sys/kern/subr_turnstile.c b/sys/kern/subr_turnstile.c
index 4e5376632b5f..2d486531a373 100644
--- a/sys/kern/subr_turnstile.c
+++ b/sys/kern/subr_turnstile.c
@@ -656,10 +656,6 @@ mtx_destroy(struct mtx *m)
 #define WITNESS_COUNT 200
 #define	WITNESS_NCHILDREN 2
 
-#ifndef SMP
-extern int witness_spin_check;
-#endif
-
 int witness_watch = 1;
 
 struct witness {
diff --git a/sys/kern/subr_witness.c b/sys/kern/subr_witness.c
index 4e5376632b5f..2d486531a373 100644
--- a/sys/kern/subr_witness.c
+++ b/sys/kern/subr_witness.c
@@ -656,10 +656,6 @@ mtx_destroy(struct mtx *m)
 #define WITNESS_COUNT 200
 #define	WITNESS_NCHILDREN 2
 
-#ifndef SMP
-extern int witness_spin_check;
-#endif
-
 int witness_watch = 1;
 
 struct witness {