Qt 5.12 and Android arm64 build

[Dirk Hohndel]

> On Nov 24, 2018, at 12:23 AM, Jan Mulder <jlmulder at xs4all.nl> wrote:
>>> 
>>> This crash can be triggered at will, by simply switching BT on/off, and unfortunately, that missing code is also triggered on a regular BT/BLE download, making the app more or less useless for any BT/BLE use at this point.
>> Not good. From the looks of it this does sound like it might be a Qt issue, so I'm adding Alex...
> 
> Something I overlooked. I was testing all the time with builds for arm64 architecture, and there I can reproduce this non-implemented jniOnReceive issue at will. However, testing for arm, all just works. That's definitely a clue, and I can definitely not rule out an issue in my build stack. The good news is that we can build a working arm version.

With Qt 5.12 scheduled for release in less than two weeks (they are now aiming for December 5th, it seems), getting a handle on whether that's an issue in your build stack or with Qt might be very interesting to Alex :-)

>>> I did review numerous recent Qt changes in the related qtconnectivity and qtbluetooth on source code level (not building Qt from source, only code reading). Nothing I found sticks out as suspicious, and nothing to really substantiate a Qt bug. So, basically I'm on a dead end at this point, and I can better go cave diving the coming days :-)
>> Be save diving.
>> Do you have pointers on how to re-create your build? Any patches needed? Specific versions?
> 
> Will push things to my github asap, but first need to do some cleanup. Notice that Qt 5.12 is not yet downloadable (as not yet released), and all my work is currently local build only. No Travis integration yet.

Thanks

Qt 5.12 is indeed downloadable. For reasons I cannot explain the folks at Qt make it rather hard to discover WHERE to download it. I guess if you don't know where to go, it's not meant for you? I don't know. But it takes quite some clicking around to stumble across this link it seems:

http://download.qt.io/development_releases/qt/5.12/5.12.0-rc/

Anyway, I'll play with this today and see if I can get it to work as well.

/D