[Development] Proposing CMake as build tool for Qt 6

[Tor Arne Vestbø]

> On 6 Jun 2019, at 15:45, Lars Knoll <lars.knoll at qt.io> wrote:
> 
> 
> 
>> On 6 Jun 2019, at 15:33, Иван Комиссаров <abbapoh at gmail.com> wrote:
>> 
>> Sorry, but the iOS should be properly supported before making the final decision.
>> Building something on macOS is easy, building smth for iOS is harder. From the top of my head it is code signing and building "fat" binaries that should be tested as a proof of concept.
> 
> Code signing has been out of scope for qmake as well, so that doesn’t count.
> 
> I really wonder how important ‘fat’ binaries/mulitarch builds are for iOS these days, given that Apple doesn’t support armv7 anymore. IMO, we can live without those. But I agree that I’d like to have a regular armv8 build of Qt for iOS working.

The fat part is important to have one build support both simulator and device. Apple is also with Xcode 11 launching something they call XCFrameworks:

"XCFrameworks make it possible to bundle a binary framework or library for multiple platforms —including iOS devices, iOS simulators, and UIKit for Mac — into a single distributable .xcframework bundle that your developers can use within their own applications. An .xcframework bundle can be added to an Xcode target’s Link Libraries phase and Xcode uses the right platform’s version of the included framework or library at build time. Creation of XCFrameworks is supported from the command line using xcodebuild -create-xcframework. Frameworks or libraries bundled in an XCFramework should be built with the Build Libraries for Distribution build setting set to YES. (49948269)"

https://developer.apple.com/documentation/xcode_release_notes/xcode_11_beta_release_notes?language=objc

Tor Arne