diff --git a/lib/libc/rpc/key_call.c b/lib/libc/rpc/key_call.c
index 6f9c0813e030..8263e3aeb708 100644
--- a/lib/libc/rpc/key_call.c
+++ b/lib/libc/rpc/key_call.c
@@ -94,7 +94,8 @@ key_setsecret(secretkey)
 {
 	keystatus status;
 
-	if (!key_call((u_long) KEY_SET, (xdrproc_t)xdr_keybuf, secretkey,
+	if (!key_call((u_long) KEY_SET, (xdrproc_t)xdr_keybuf,
+			(void *)secretkey,
 			(xdrproc_t)xdr_keystatus, &status)) {
 		return (-1);
 	}