[Development] thread_local: replacing GCC with Clang for MinGW

[Olivier Goffart]

On 24.08.19 18:04, Thiago Macieira wrote:

> [...] That means we must continue to use
> QThreadStorage where we need non-POD thread-local storage, which only works[*]
> in QThread-started threads.
> 
> [*] it won't crash if you use QThreadStorage with a thread started with
> something else, despite what the source code says, but it will leak memory.

The leak will only happen on Windows.

One could fix the leak by re-implementing DllMain in QtCore and using the 
DLL_THREAD_DETACH hook to delete the QAdoptedThread
https://docs.microsoft.com/en-us/windows/win32/dlls/dllmain

That would fix the leak for dynamic Qt build.

But for static build we would need another trick.
The comments from this file are pretty interesting and would provide a solution:
https://github.com/rust-lang/rust/blob/master/src/libstd/sys/windows/thread_local.rs#L130

-- 
Olivier

Woboq - Qt services and support - https://woboq.com - https://code.woboq.org