Spurious LNK1104 error on `x86_64-msvc` in `nll` revision on run-pass tests

[kennytm]

Symptom: A run-pass test, or a UI test with a // run-pass header failed due to linker error LNK1104. The error message looks like cannot open file C:\projects\**\*.stage2-x86_64-pc-windows-msvc.exe. Interestingly, it only affects tests in the nll revision, if any.

Known instances:

• Rollup of 14 pull requests #49939 (comment)
• Fix Iter exhaustion in prove_predicates when debug is on #50076 (comment)

[Enselic]

Triage: Has this been seen recently? If not I think we can close this issue as obsolete since it now is 5 years old.

[ChrisDenton]

I don't recall ever seeing it locally. And, yeah, I'd agree that no comments in 5 years suggests it hasn't been happening in CI.

[kennytm]

Let's reopen if this actually happens again.