diff --git a/sys/kern/kern_sig.c b/sys/kern/kern_sig.c
--- a/sys/kern/kern_sig.c
+++ b/sys/kern/kern_sig.c
@@ -214,7 +214,6 @@
 #define	SIGPROP_TTYSTOP		0x08	/* ditto, from tty */
 #define	SIGPROP_IGNORE		0x10	/* ignore by default */
 #define	SIGPROP_CONT		0x20	/* continue if suspended */
-#define	SIGPROP_CANTMASK	0x40	/* non-maskable, catchable */
 
 static int sigproptbl[NSIG] = {
 	[SIGHUP] =	SIGPROP_KILL,