[Development] Dropping MinGW support in Qt 6 (Was: HEADS-UP: QStringLiteral)

[Thiago Macieira]

On Wednesday, 21 August 2019 11:35:37 PDT Mathias Hasselmann wrote:
> Am 21.08.2019 um 19:38 schrieb Thiago Macieira:
> > PPS: can we drop MinGW support in Qt 6?
> 
> What alternative do you propse?

Clang/MinGW. However, after a quick test, turns out that this code only 
compiles under Clang trunk. Not even Clang 8 can compile it:

struct S { S(); ~S(); };

void f()
{
    thread_local S s;
}

https://mingw.godbolt.org/z/nzHBEH
error: cannot compile this non-trivial TLS destruction yet

The same code compiled with the GCC/MinGW 8.2 that I have on my openSUSE 
system. (I'd have tested GCC/MinGW on Windows, but the terminal and/or bash 
refuse to paste text) I don't know when GCC implemented the functionality.

So let me instead change my request:
Can we require GCC 8 for MinGW for Qt 5.15?

That way, we can ressurrect Q_THREAD_LOCAL and eventually replace with 
thread_local.

-- 
Thiago Macieira - thiago.macieira (AT) intel.com
  Software Architect - Intel System Software Products