Port backtrace-rs test-crates to rustc repo about rust HOT 8 OPEN

I'll take a stab at porting line-tables-only

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Hi, I'll pick this up cpp_smoke_test

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@jieyouxu I think I'll have to reimagine the test somewhat and port it myself, yeah! it can be run under the rustc test suite but it requires doing something mildly silly because what it is really doing is testing that you "don't lose track" of the debuginfo.

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The without_debuginfo test has been unblocked by #123081 landing.

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The tests using C may be able to make use of tests/auxiliary/rust_test_helpers.c.

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I don't think debuglink can be easily ported over to the rustc test suite without the test suite having access to docker? The problem is that the test wants to test debug directories under /usr/lib/debug, which seems like a massive no-no without docker. I don't think there is a very elegant solution for that? Even if it was possible to run docker inside docker (as in rustc's CI), that seems to be a bad idea in itself.

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The without_debuginfo test has been unblocked by #123081 landing.

That test is also unfortunately a bit awkward because it's checking if each frame with a non-null IP has resolved symbols even if -Cdebuginfo=0... which is awkward to check with std::backtrace::Backtrace because AFAICT the frame IP is not exposed.

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We could add more methods to BacktraceFrame. Might require an ACP though.

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