win64/msvc: large or oddly-sized types pass by-ref

[tari]

Fixes #28676.

There doesn't seem to be a good way to add a test for this, but I tested the repro in #28676 and confirmed it now yields the correct result.

[rust-highfive]

r? @arielb1

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[alexcrichton]

I think a test can be added for this by perhaps modifying src/rt/rust_test_helpers.c or enabling an existing test on Windows (it may be ignored somewhere), perhaps that could validate this fix?

[tari]

Nothing relevant that was ignored on windows, so added a function to rust_test_helpers and a test case to exercise it.

[luqmana]

@bors: r+

I'll add more tests as part of #27017 since this plus some changes should unblock it on that end. Thanks!

[bors]

📌 Commit 95721d3 has been approved by luqmana

[bors]

⌛ Testing commit 95721d3 with merge eafe106...

[bors]

☀️ Test successful - auto-linux-32-nopt-t, auto-linux-32-opt, auto-linux-64-nopt-t, auto-linux-64-opt, auto-linux-64-x-android-t, auto-mac-32-opt, auto-mac-64-nopt-t, auto-mac-64-opt, auto-win-gnu-32-nopt-t, auto-win-gnu-32-opt, auto-win-gnu-64-nopt-t, auto-win-gnu-64-opt, auto-win-msvc-32-opt, auto-win-msvc-64-opt