Consider the following QML code

import QtQuick
import QtQuick.Controls as QQC2

Window {
    QQC2.Label {
        text: i18n("Display Style")
    }
} 

Compiling with qmlcachegen in verbose mode gives (among others) the following warning

> Warning: Main.qml:6:9: Cannot resolve property type  for binding on text. [compiler]

note the double space between type and for. It appears that there's supposed to be a type name there, but there isn't.

i18n() in this case is a KDE function injected via setContextObject, so not visible to the compiler. Getting that to work properly is a whole other topic.

qtdeclarative commit b75f34458f6060385b3cdcc46ce8e8e87f661251