From aa1854a8fffbcd1144b64fc25485ae71a6e6f4cf Mon Sep 17 00:00:00 2001
From: Viktor Szakats <commit@vsz.me>
Date: Thu, 19 Feb 2026 18:34:35 +0100
Subject: [PATCH] tests/server/sockfilt: check for NULL `tv` to silence
 clang-tidy

A NULL dereference cannot happen with existing use of this code.

linux-mingw, CM clang-tidy:
```
/home/runner/work/curl/curl/tests/server/sockfilt.c:720:24: error: Access
 to field 'tv_sec' results in a dereference of a null pointer (loaded from
 variable 'tv') [clang-analyzer-core.NullDereference,-warnings-as-errors]
  720 |             tv->tv_sec = 0;
      |             ~~         ^
```
Ref: https://github.com/curl/curl/actions/runs/22191200093/job/64179197235?pr=20631#step:10:283

Cherry-picked from #20631

Closes #20639
---
 tests/server/sockfilt.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/tests/server/sockfilt.c b/tests/server/sockfilt.c
index 6bdd5633b1..42a4ad1079 100644
--- a/tests/server/sockfilt.c
+++ b/tests/server/sockfilt.c
@@ -717,8 +717,10 @@ static int select_ws(int nfds, fd_set *readfds, fd_set *writefds,
             data[nws].wsasock = wsasock;
             data[nws].wsaevent = wsaevent;
             data[nfd].wsastate = 0;
-            tv->tv_sec = 0;
-            tv->tv_usec = 0;
+            if(tv) {
+              tv->tv_sec = 0;
+              tv->tv_usec = 0;
+            }
             /* check if the socket is already ready */
             if(select(fd + 1, &readsock, &writesock, &exceptsock, tv) == 1) {
               logmsg("[select_ws] socket %d is ready", fd);