apple
diff --git a/src/cmd/ed.c b/src/cmd/ed.c
index f44acb0..60ba83c 100644
--- a/src/cmd/ed.c
+++ b/src/cmd/ed.c
@@ -929,7 +929,7 @@
 	*p = 0;
 	pid = fork();
 	if(pid == 0) {
-		execlp("rc", "rc", "-c", buf, 0);
+		execlp("rc", "rc", "-c", buf, (char*)0);
 		sysfatal("exec failed: %r");
 		exits("execl failed");
 	}