I resubmitted the MR a bunch of times, tightening the handling of uninitialized memory around the IRP requests in an attempt to fix the test failures (that I cannot reproduce on my computer), but I now believe the test failures to be unrelated to my changes and instead be caused by [recently-introduced](https://gitlab.winehq.org/wine/wine/-/commit/200d7b25eccc96a740b902aa59c86fe...) flaky tests (thanks to fgouget for pointing that out).
Some of those tightening changes, such as 6bb00498b8a2b14e727455dd9732502436fb3134, are most probably unnecessary, but I will leave them in unless requested otherwise.