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Auto merge of #115005 - compiler-errors:passes, r=cjgillot

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Don't do intra-pass validation on MIR shims

Fixes #114375

In the test that was committed, we end up generating the drop shim for `struct Foo` that looks like:

```
fn std::ptr::drop_in_place(_1: *mut Foo) -> () {
    let mut _0: ();

    bb0: {
        goto -> bb5;
    }

    bb1: {
        return;
    }

    bb2 (cleanup): {
        resume;
    }

    bb3: {
        goto -> bb1;
    }

    bb4 (cleanup): {
        drop(((*_1).0: foo::WrapperWithDrop<()>)) -> [return: bb2, unwind terminate];
    }

    bb5: {
        drop(((*_1).0: foo::WrapperWithDrop<()>)) -> [return: bb3, unwind: bb2];
    }
}
```

In `bb4` and `bb5`, we assert that `(*_1).0` has type `WrapperWithDrop<()>`. However, In a user-facing param env, the type is actually `WrapperWithDrop<Tait>`. These types are not equal in a user-facing param-env (and can't be made equal even if we use `DefiningAnchor::Bubble`, since it's a non-local TAIT).
This commit is contained in:
bors 2023-08-22 22:04:49 +00:00
commit c469197b19
3 changed files with 36 additions and 1 deletions
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6
compiler/rustc_mir_transform/src/shim.rs
View file

@ -99,7 +99,11 @@ fn make_shim<'tcx>(tcx: TyCtxt<'tcx>, instance: ty::InstanceDef<'tcx>) -> Body<'
};
debug!("make_shim({:?}) = untransformed {:?}", instance, result);
pm::run_passes(
// We don't validate MIR here because the shims may generate code that's
// only valid in a reveal-all param-env. However, since we do initial
// validation with the MirBuilt phase, which uses a user-facing param-env.
// This causes validation errors when TAITs are involved.
pm::run_passes_no_validate(
tcx,
&mut result,
&[