[Development] Qt for WebAssembly

[Morten Sørvig]

> On 9 Mar 2018, at 13:57, Morten Sørvig <Morten.Sorvig at qt.io> wrote:
> 
> * (No) thread support
> 
>  Wasm and Emscripten do have pthreads support. However this requires SharedArrayBuffer, 
>  which has been disabled in all major browser after recent security incidents.
> 
>  So we are looking to upstream a no-thread configure option, and modules that
>  want to work on the web should support it. It’s still possible to develop with
>  pthreads enabled by enabling SharedArrayBuffer for your browser.


It was pointed out to me that we already have pending patches in this area:

https://codereview.qt-project.org/181112
https://codereview.qt-project.org/180973
https://codereview.qt-project.org/180971
https://codereview.qt-project.org/180972
https://codereview.qt-project.org/177459

I suggest we restore and merge those since we now have an additional use
case in the form of a platform requirement.

(The alternative would be to wait it out - perhaps threading support will be
enabled and stable in all browsers before we get to merge wip/webassembly).

Morten