Thank you very much @oliver_mpt
I get the same problem trying to compile CopyQ 14.0 against Qt 6.11.0 on Windows 11.
Thank you very much @JonB
I was using version 11 and tried using a newer MinGW-w64, and I managed to compile using version 14. But it fails to link. I'm too ignorant about Qt, C++ and C toolchains to judge, but there is a good chance that going from version 11 to 14 suffices to fix that specific issue. I did not need to define NTDDI_VERSION.
Unfortunately I do not know for sure because I got version 14 from MSYS2 instead of Qt, so they're very different beasts, which is very likely to explain the linking failure.
How were you able to get MinGW-w64 13 from Qt? One thing I noticed is it's complicated to see which version of MinGW-w64 a directory contains.
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