add tests which assert that import list for simple executable not changed silently

[klensy]

added tests for x86_64-pc-windows-msvc and x86_64-unknown-linux-gnu

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[ChrisDenton]

Is there are reason this in particular is useful? I would expect this to change as the C runtime changes between versions. And also a fair bit on the Rust side over time, especially around now as we're moving to a Windows 10 baseline.

[klensy]

Yes, but runtime changes not every day, same is true for transition to Windows 10 baseline (windows dependency list should be quite stable, but don't know about linux ones).

Plus this is additional guard against issues like #85441, #108714 (comment)

[klensy]

I'll probably add more variations to tests, like lto and stuff, they cut import list quite nice ,for example for x86_64-pc-windows-gnu

[klensy]

@author

[Dylan-DPC]

@klensy any updates on this? thanks

[ChrisDenton]

While I remain nervous about this (e.g. the CRT could add or remove DLLs) I am broadly in favour.

Maybe with the modern rust run-make tests we could use the object crate to gather imports? And, for Windows, compare with a list of known functions for Windows 1507? That would seem more robust than having to add or remove imports if something changes.