BUILD: quic: fix unused variable warning when threads are disabled

The tree variable was introduced in 3.0 by commit dd58dff1e6
("BUG/MEDIUM: quic: QUIC CID removed from tree without locking") which
was marked for backport. The variable is only used for locks.
Let's just mark the variable __maybe_unused for when the code is
built without threads.

The patch above was marked for backport to 2.7 so this should be
backported wherever the fix was backported.

diff --git a/src/quic_rx.c b/src/quic_rx.c
index 3645f1673d43f7295aca182e6dc41eb26b4c71fd..f530c443b0b727af70a6c5a66493e02ba9228475 100644 (file)
--- a/src/quic_rx.c
+++ b/src/quic_rx.c
@@ -982,7 +982,7 @@ static int qc_parse_pkt_frms(struct quic_conn *qc, struct quic_rx_packet *pkt,
                        break;
                case QUIC_FT_RETIRE_CONNECTION_ID:
                {
-                       struct quic_cid_tree *tree;
+                       struct quic_cid_tree *tree __maybe_unused;
                        struct quic_connection_id *conn_id = NULL;
 
                        if (!qc_handle_retire_connection_id_frm(qc, &frm, &pkt->dcid, &conn_id))