[ios] Regression QMake -> CMake: slow build time due to file copying and qmlcachegen

Starting with Qt 6.7 I also started with CMake, so I don't know if this slowdown started with 6.7 or before. Compared with QMake I noticed a very slow build time for iOS, if doing

• Build Clean
• Build

In one of my apps (not the largest one) I got these times for Build:

• CMake - Android - 01:27
• CMake - iOS - 12:58
• QMake - iOS - 01.04

13 Minutes to build - on a Mac Pro ! This slows down my workflow drastically.

Imagine implementing new features into 10 apps...

Tried also Qt 6.7.1 Example App 'Coffee':

• CMake - Android - 00:15
• CMake - iOS - 01:17

I timed it and realised that most of the time is spent with

PhaseScriptExecution...Generate...tooling.build/Script...

for QML- and RESOURCES- files.

see log file

later - when building without build clean it varies: 2 or 4 minutes, and sometimes the whole 13 minutes.