ICE: `called Option::unwrap() on a None value in rustc_middle/src/mir/tcx.rs`

### Code

(hand-reduced)

```Rust
#![feature(generic_const_exprs)]
#![allow(incomplete_features)]

trait Foo {
 type Output;
}

impl Foo for [u8; 3] {
 type Output = [u8; 3];
}

static A: <[u8; N] as Foo>::Output = [1, 2, 3];

fn main() {
 || {
 let _ = A[1];
 };
}
```

<details><summary>(original)</summary>


```Rust
//@ build-pass

#![feature(generic_const_exprs)]
#![allow(incomplete_features)]

trait Foo {
 type Output;

 fn foo() -> Self::Output;
}

impl Foo for [u8; 3] {
 type Output = [u8; 1 + 2];

 fn foo() -> [u8; 3] {
 [1u8; 3]
 }
}

fn bug<const N: usize>()
where
 [u8; N]: Foo,
 <[u8; N] as Foo>::Output: AsRef<[u8]>,
{
 <[u8; N]>::foo().as_ref();
}

fn main() {
 bug::<3>();
}


//@ build-pass
#![feature(coroutines)]

static A: <[u8; N] as Foo>::Output = [1, 2, 3, 4, 5];

fn main() {
 #[coroutine] static || {
 let u = A[{yield; 1}];
 };
 #[coroutine] static || {
 match A {
 i if { yield; true } => (),
 _ => (),
 }
 };
}
```


</details>


### Meta


`rustc --version --verbose`:
```
rustc 1.80.0-nightly (6f3df08aa 2024-05-30)
binary: rustc
commit-hash: 6f3df08aadf71e8d4bf7e49f5dc10dfa6f254cb4
commit-date: 2024-05-30
host: x86_64-apple-darwin
release: 1.80.0-nightly
LLVM version: 18.1.6
```

### Error output

Command: `rustc`

```
error[E0425]: cannot find value `N` in this scope
 --> r_tcx_1F6082.rs:12:17
 |
12 | static A: <[u8; N] as Foo>::Output = [1, 2, 3];
 | ^ not found in this scope
```


<details><summary>Backtrace</summary>


```
thread 'rustc' panicked at compiler/rustc_middle/src/mir/tcx.rs:88:58:
called `Option::unwrap()` on a `None` value
stack backtrace:
 0: _rust_begin_unwind
 1: core::panicking::panic_fmt
 2: core::panicking::panic
 3: core::option::unwrap_failed
 4: <rustc_middle::mir::tcx::PlaceTy>::projection_ty
 5: <rustc_mir_build::build::matches::MatchPair>::new
 6: <rustc_mir_build::build::matches::FlatPat>::new
 7: <rustc_mir_build::build::Builder>::place_into_pattern
 8: <rustc_mir_build::build::Builder>::ast_block_stmts
 9: <rustc_mir_build::build::Builder>::expr_into_dest
 10: <rustc_mir_build::build::Builder>::expr_into_dest::{closure#0}
 11: <rustc_mir_build::build::Builder>::expr_into_dest
 12: rustc_mir_build::build::construct_fn
 13: rustc_mir_build::build::mir_build
 14: rustc_mir_transform::mir_built
 [... omitted 1 frame ...]
 15: <rustc_mir_build::check_unsafety::UnsafetyVisitor>::visit_inner_body
 16: <rustc_mir_build::check_unsafety::UnsafetyVisitor as rustc_middle::thir::visit::Visitor>::visit_expr
 17: <rustc_mir_build::check_unsafety::UnsafetyVisitor as rustc_middle::thir::visit::Visitor>::visit_expr
 18: rustc_middle::thir::visit::walk_block::<rustc_mir_build::check_unsafety::UnsafetyVisitor>
 19: <rustc_mir_build::check_unsafety::UnsafetyVisitor as rustc_middle::thir::visit::Visitor>::visit_expr
 20: <rustc_mir_build::check_unsafety::UnsafetyVisitor as rustc_middle::thir::visit::Visitor>::visit_expr
 21: rustc_mir_build::check_unsafety::check_unsafety
 [... omitted 1 frame ...]
 22: <rustc_middle::hir::map::Map>::par_body_owners::<rustc_interface::passes::run_required_analyses::{closure#1}::{closure#0}>::{closure#0}
 23: rustc_interface::passes::run_required_analyses
 24: rustc_interface::passes::analysis
 [... omitted 1 frame ...]
 25: <rustc_interface::queries::QueryResult<&rustc_middle::ty::context::GlobalCtxt>>::enter::<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}::{closure#1}::{closure#3}>
 26: rustc_interface::interface::run_compiler::<core::result::Result<(), rustc_span::ErrorGuaranteed>, rustc_driver_impl::run_compiler::{closure#0}>::{closure#1}
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

error: the compiler unexpectedly panicked. this is a bug.

note: we would appreciate a bug report: https://github.com/rust-lang/rust/issues/new?labels=C-bug%2C+I-ICE%2C+T-compiler&template=ice.md

note: please make sure that you have updated to the latest nightly

note: please attach the file at `/Volumes/T7/workspace/240530_100chaos_tree_combine_typ/icefiles/rustc-ice-2024-05-31T07_58_41-11292.txt` to your bug report

query stack during panic:
#0 [mir_built] building MIR for `main::{closure#0}`
#1 [check_unsafety] unsafety-checking `main`
#2 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0425`.
```


</details>

### Note
- ICE location: `rustc_middle/src/mir/tcx.rs L88`
 https://github.com/rust-lang/rust/blob/6f3df08aadf71e8d4bf7e49f5dc10dfa6f254cb4/compiler/rustc_middle/src/mir/tcx.rs#L80-L89

	let answer = match *elem {
	ProjectionElem::Deref => {
	let ty = self.ty.builtin_deref(true).unwrap_or_else(\|\| {
	bug!("deref projection of non-dereferenceable ty {:?}", self)
	});
	PlaceTy::from_ty(ty)
	}
	ProjectionElem::Index(_) \| ProjectionElem::ConstantIndex { .. } => {
	PlaceTy::from_ty(self.ty.builtin_index().unwrap())
	}

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ICE: `called Option::unwrap() on a None value in rustc_middle/src/mir/tcx.rs` #125801

cushionbadak
openedon May 31, 2024

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ICE: called Option::unwrap() on a None value in rustc_middle/src/mir/tcx.rs #125801

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cushionbadakopenedon May 31, 2024