Unable to test early finalization prevention

[jacob-hughes]

Early finalization prevention is done with the prevent_early_finalization MIR transformation. It's not possible to test this with a mir-opt test because diffing MIR generated from the alloc crate leads to different output on different architectures. The crate hash for alloc::Gc is pulled in and that changes depending on which machine compiles the test. Although this isn't necessary to show that early finalization was prevented, right now there's no way to use a wildcard for this particular output when comparing the diffs.

[ltratt]

I think we can close this issue?