diff --git a/include/unistd.h b/include/unistd.h
index ef77133d0ba5..4c26a042674e 100644
--- a/include/unistd.h
+++ b/include/unistd.h
@@ -327,9 +327,9 @@ int	 close(int);
 void	 closefrom(int);
 int	 dup(int);
 int	 dup2(int, int);
-int	 execl(const char *, const char *, ...) __sentinel;
+int	 execl(const char *, const char *, ...) __null_sentinel;
 int	 execle(const char *, const char *, ...);
-int	 execlp(const char *, const char *, ...) __sentinel;
+int	 execlp(const char *, const char *, ...) __null_sentinel;
 int	 execv(const char *, char * const *);
 int	 execve(const char *, char * const *, char * const *);
 int	 execvp(const char *, char * const *);
diff --git a/sys/sys/cdefs.h b/sys/sys/cdefs.h
index 3eaf17bac2bf..59cc45f0e5fa 100644
--- a/sys/sys/cdefs.h
+++ b/sys/sys/cdefs.h
@@ -459,11 +459,11 @@
 #endif
 
 #if __GNUC_PREREQ__(4, 0)
-#define	__sentinel	__attribute__((__sentinel__))
+#define	__null_sentinel	__attribute__((__sentinel__))
 #define	__exported	__attribute__((__visibility__("default")))
 #define	__hidden	__attribute__((__visibility__("hidden")))
 #else
-#define	__sentinel
+#define	__null_sentinel
 #define	__exported
 #define	__hidden
 #endif