diff --git a/libc/dns/resolv/res_send.c b/libc/dns/resolv/res_send.c
index b6a990a..4a010d5 100644
--- a/libc/dns/resolv/res_send.c
+++ b/libc/dns/resolv/res_send.c
@@ -764,7 +764,7 @@
 		struct sockaddr_storage peer;
 		socklen_t size = sizeof peer;
 		unsigned old_mark;
-		int mark_size = sizeof(old_mark);
+		socklen_t mark_size = sizeof(old_mark);
 		if (getpeername(statp->_vcsock,
 				(struct sockaddr *)(void *)&peer, &size) < 0 ||
 		    !sock_eq((struct sockaddr *)(void *)&peer, nsap) ||