[Bug 42695] Path of Exile fails to start when launching with dx11 enabled with message "Failed to create WIC factory" (CoCreateInstance() called in uninitialized apartment)

[wine-bugs at winehq.org]

https://bugs.winehq.org/show_bug.cgi?id=42695

--- Comment #44 from Paul Gofman <gofmanp at gmail.com> ---
I downloaded the game and tried to track down what's happening there. While
forcing CoInitializeSecurity() to return error unconditionally is occasionally
pushing app to work (it skips CoUnitialize() in this case), this is no more
than another hack as it does not fail in the application running on Windows.
Before discovering that I tested some legit cases for CoInitializeSecurity() to
fail (that is, if security was already initialized in any thread), but nothing
like this is related here as Nikolay said.

On Windows CoCreateInstance() succeeds for WICImagingFactory, while COM is
seemingly not initialized. I tested that injecting CoInitialize() calls before
or after successful CoCreateInstance() returns S_OK (not S_FALSE) which
suggests COM was not initialized before this call. The only documented way how
this can happen which I knew or could find is a thread created from some thread
which has MTA initialized. But this is not the case here (CoCreateInstance()
under discussion happens in main thread, and no other thread initializes MTA
apartment). Besides, this case is supported in Wine. I tried to track down what
triggers CoCreateInstance() to succeed by injecting the calls to the code
creating WICImagingFactory at different points, and found that the call starts
to succeed after SetWindowPlacement() call for the application window created
like this:

002a:Call user32.CreateWindowExW(00000000,1413ce2c8 L"POEWindowClass",1413cdde8
L"Path of
Exile",00cf0000,80000000,80000000,00000328,00000273,00000000,00000000,140000000,00000000)
ret=140c48753

I also found some mentioning of the mysterious CoCreateInstance() success after
ShowWindow() on the internet:
https://social.msdn.microsoft.com/Forums/vstudio/en-US/c1a642e2-184e-4f5a-984a-e30bdfe97fb8/does-createwindowexa-calls-coinitialize-internally?forum=windowsgeneraldevelopmentissues.
I checked library calls utilized from the window procedure of the application
window and did not find anything relevant. Yet I did not test it thoroughly, so
it leaves some room for mistake.

I did not yet reproduce that case on an standalone test, but I am not sure all
this has any practical sense, as carefully reconstructing the conditions of
this out-of-init CoCreateInstances and reproducing this behavior looks unlikely
feasible at the moment. And I hope game developers will add an explicit
CoInitializeEx() at some point.

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