QML: Warn about variables being used before their declaration

This collides with injected signal parameters. qmlcachegen cannot tell
those cases apart.

[ChangeLog][QML][Important Behavior Changes] QML warns about JavaScript
variables being used before their declaration now. This is almost always
a mistake. It is particularly dangerous in the presence of injected
signal parameters because qmlcachegen cannot identify a name collision
between an injected signal parameter and a variable being used before
its declaration. It therefore miscompiles such code. You can turn off
the deprecation warning using the "qt.qml.compiler" logging category.

Task-number: QTBUG-89943
Change-Id: I8a9424ca8c6edd562402fe5c560ba7e8344b5585
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
(cherry picked from commit ab71cdafca87513a4e214d3af056d8990bc1eddb)
Reviewed-by: Andrei Golubev <andrei.golubev@qt.io>

0 files changed, 0 insertions, 0 deletions