Jinoh Kang (@iamahuman) commented about dlls/win32u/input.c:
- SERVER_START_REQ( set_cursor )
- while (get_shared_desktop( &lock )) {
if ((ret = !wine_server_call( req )))
SHARED_READ_BEGIN( &lock.shared->desktop, desktop_shm_t ) {
pt->x = reply->new_x;pt->y = reply->new_y;last_change = reply->last_change;
if ((valid = lock.id == shared->obj.id)){pt->x = shared->cursor.x;pt->y = shared->cursor.y;last_change = shared->cursor.last_change;ret = TRUE;}
Solution: For the reasons above, I think we should just abolish `if()`s that depend on shared memory value.[^1]
```suggestion:-6+0 valid = lock.id == shared->obj.id; pt->x = shared->cursor.x; pt->y = shared->cursor.y; last_change = shared->cursor.last_change; ```
[^1]: Previously, I thought `if()`s were more or less harmless in seqlocks if used carefully. Now that I think about it, the shared object can get invalid *at any time* and turn into another object type (e.g., `valid` might be set to TRUE but then subsequent reads like `shared->cursor.x` might return inconsistent value, before the shared read loop detects seq change and retries).