diff --git a/dwl.c b/dwl.c
index fa6379a..518e544 100644
--- a/dwl.c
+++ b/dwl.c
@@ -1883,7 +1883,7 @@ run(char *startup_cmd)
 		if (startup_pid < 0)
 			EBARF("startup: fork");
 		if (startup_pid == 0) {
-			execl("/bin/sh", "/bin/sh", "-c", startup_cmd, (void *)NULL);
+			execl("/bin/sh", "/bin/sh", "-c", startup_cmd, NULL);
 			EBARF("startup: execl");
 		}
 	}