diff --git a/include/err.h b/include/err.h
index dce9ed0ea310..8236f0077606 100644
--- a/include/err.h
+++ b/include/err.h
@@ -47,10 +47,10 @@
 #include <sys/cdefs.h>
 
 __BEGIN_DECLS
-__dead void	err __P((int, const char *, ...));
-__dead void	verr __P((int, const char *, _BSD_VA_LIST_));
-__dead void	errx __P((int, const char *, ...));
-__dead void	verrx __P((int, const char *, _BSD_VA_LIST_));
+__dead void	err __P((int, const char *, ...)) __dead2;
+__dead void	verr __P((int, const char *, _BSD_VA_LIST_)) __dead2;
+__dead void	errx __P((int, const char *, ...)) __dead2;
+__dead void	verrx __P((int, const char *, _BSD_VA_LIST_)) __dead2;
 void		warn __P((const char *, ...));
 void		vwarn __P((const char *, _BSD_VA_LIST_));
 void		warnx __P((const char *, ...));
diff --git a/include/stdlib.h b/include/stdlib.h
index 80cd3619b19f..31fa8e39a0e8 100644
--- a/include/stdlib.h
+++ b/include/stdlib.h
@@ -77,7 +77,7 @@ extern int __mb_cur_max;
 
 __BEGIN_DECLS
 __dead void
-	 abort __P((void));
+	 abort __P((void)) __dead2;
 __pure int
 	 abs __P((int));
 int	 atexit __P((void (*)(void)));
@@ -90,7 +90,7 @@ void	*calloc __P((size_t, size_t));
 __pure div_t
 	 div __P((int, int));
 __dead void
-	 exit __P((int));
+	 exit __P((int)) __dead2;
 void	 free __P((void *));
 char	*getenv __P((const char *));
 __pure long
diff --git a/include/unistd.h b/include/unistd.h
index 4595a9d114e6..9db3112af4c2 100644
--- a/include/unistd.h
+++ b/include/unistd.h
@@ -50,7 +50,7 @@
 
 __BEGIN_DECLS
 __dead void
-	 _exit __P((int));
+	 _exit __P((int)) __dead2;
 int	 access __P((const char *, int));
 unsigned int	 alarm __P((unsigned int));
 int	 chdir __P((const char *));