diff --git a/channels/chan_sip.c b/channels/chan_sip.c
index 0cffb9e969..103c295a03 100644
--- a/channels/chan_sip.c
+++ b/channels/chan_sip.c
@@ -7309,7 +7309,7 @@ static int process_sdp(struct sip_pvt *p, struct sip_request *req, int t38action
 		ast_log(LOG_WARNING, "SDP syntax error in o= line\n");
 		return -1;
 	}
-	if (!sscanf(token, "%" __PRI64_PREFIX "u", &rua_version)) {
+	if (!sscanf(token, "%" SCNu64, &rua_version)) {
 		ast_log(LOG_WARNING, "SDP syntax error in o= line version\n");
 		return -1;
 	}