diff --git a/usr.bin/make/job.c b/usr.bin/make/job.c
index e7220105387f..e37c62c621e6 100644
--- a/usr.bin/make/job.c
+++ b/usr.bin/make/job.c
@@ -342,7 +342,7 @@ static int	fifoFd;		/* Fd of our job fifo */
 static char	fifoName[] = "/tmp/make_fifo_XXXXXXXXX";
 static int	fifoMaster;
 
-static sig_atomic_t interrupted;
+static volatile sig_atomic_t interrupted;
 
 
 #if defined(USE_PGRP) && defined(SYSV)
diff --git a/usr.sbin/mount_portalfs/mount_portalfs.c b/usr.sbin/mount_portalfs/mount_portalfs.c
index 9a8c49c6787e..8f61efcc964c 100644
--- a/usr.sbin/mount_portalfs/mount_portalfs.c
+++ b/usr.sbin/mount_portalfs/mount_portalfs.c
@@ -70,7 +70,7 @@ struct mntopt mopts[] = {
 
 static void usage(void) __dead2;
 
-static sig_atomic_t readcf;	/* Set when SIGHUP received */
+static volatile sig_atomic_t readcf;	/* Set when SIGHUP received */
 
 static void sighup(int sig __unused)
 {
diff --git a/usr.sbin/ngctl/main.c b/usr.sbin/ngctl/main.c
index f998513a8e2b..919554615e74 100644
--- a/usr.sbin/ngctl/main.c
+++ b/usr.sbin/ngctl/main.c
@@ -79,7 +79,7 @@ static int	ReadCmd(int ac, char **av);
 static int	HelpCmd(int ac, char **av);
 static int	QuitCmd(int ac, char **av);
 #ifdef EDITLINE
-static sig_atomic_t	unblock;
+static volatile sig_atomic_t unblock;
 static pthread_mutex_t	mutex = PTHREAD_MUTEX_INITIALIZER;
 static pthread_cond_t	cond = PTHREAD_COND_INITIALIZER;
 #endif