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Rollup merge of #127136 - compiler-errors:coroutine-closure-env-shim, r=oli-obk

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Fix `FnMut::call_mut`/`Fn::call` shim for async closures that capture references

I adjusted async closures to be able to implement `Fn` and `FnMut` *even if* they capture references, as long as those references did not need to borrow data from the closure captures themselves. See #125259.

However, when I did this, I didn't actually relax an assertion in the `build_construct_coroutine_by_move_shim` shim code, which builds the `Fn`/`FnMut`/`FnOnce` implementations for async closures. Therefore, if we actually tried to *call* `FnMut`/`Fn` on async closures, it would ICE.

This PR adjusts this assertion to ensure that we only capture immutable references in closures if they implement `Fn`/`FnMut`. It also adds a bunch of tests and makes more of the async-closure tests into `build-pass` since we often care about these tests actually generating the right closure shims and stuff. I think it might be excessive to *always* use build-pass here, but 🤷 it's not that big of a deal.

Fixes #127019
Fixes #127012

r? oli-obk
This commit is contained in:
Matthias Krüger 2024-07-02 17:47:46 +02:00 • committed by GitHub
commit 3cf567e3c0
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23 changed files with 225 additions and 58 deletions
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4
compiler/rustc_ty_utils/src/abi.rs
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@ -127,9 +127,9 @@ fn fn_sig_for_fn_abi<'tcx>(
coroutine_kind = ty::ClosureKind::FnOnce;
// Implementations of `FnMut` and `Fn` for coroutine-closures
// still take their receiver by (mut) ref.
// still take their receiver by ref.
if receiver_by_ref {
Ty::new_mut_ref(tcx, tcx.lifetimes.re_erased, coroutine_ty)
Ty::new_imm_ref(tcx, tcx.lifetimes.re_erased, coroutine_ty)
} else {
coroutine_ty
}