Call rustc_driver::main() for MIRI_BE_RUSTC=host

[bjorn3]

This way we don't need a special case in MiriBeRustCompilerCalls.

[rustbot]

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[RalfJung]

Good call, I like the general approach. We can also update a bunch of comments and names then, I think.

View changes since this review

[RalfJung]

That's annoying that we can't use return to make it clear that the call won't return... is there some other nice way to make that syntactically obvious?

[bjorn3]

match rustc_driver::main() {} works.

[bjorn3]

@rustbot ready

[RalfJung]

LGTM, thanks! r=me after adding the comment and squashing.

resolved