[REG 6.2.5 -> 6.4.0] qmlcachegen crash when attempting a 'Copy sequence'

Hello,

I have attempted to replicate on of the examples from the following documentation which talks about Sequence tips (https://doc.qt.io/qt-6/qtquick-performance.html).

In the documentation there is an example of how to speed up writing to a sequence property by doing a copy sequence. I was able to replicate this code which I have attached below.

This works as intended in Qt 6.2.3, however when attempting to build this example with Qt 6.4.0 I get the error ":-1: error: ninja: build stopped: subcommand failed."

This error appears to be caused by the line "mySequence.qrealListProperty = someData;" (line 89 of main.qml in the attached example). It is unclear to me why this is happening and I believe it to be a bug as the code is nearly identical to the code from the documentation and works perfectly in previous version of Qt.