Do not ICE on AnonConsts in diagnostic_hir_wf_check

[gurry]

Fixes #122989

Below is the snippet from #122989 that ICEs:

trait Traitor<const N: N<2> = 1, const N: N<2> = N> {
    fn N(&N) -> N<2> {
        M
    }
}

trait N<const N: Traitor<2> = 12> {}

The AnonConst that triggers the ICE is the 2 in the param const N: N<2> = 1. The currently existing code in diagnostic_hir_wf_check deals only with AnonConsts that are default values of some param, but the 2 is not a default value. It is just an AnonConst HIR node inside a TraitRef HIR node corresponding to N<2>. Therefore the existing code cannot handle it and this PR ensures that it does.

[rustbot]

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[Nadrieril]

r? compiler

[compiler-errors]

@gurry: Please make sure to actually explain in your PR descriptions why something is happening and why your changes are correct, if it's not obvious from the title or the code itself. In this case, it's not really obvious

[compiler-errors]

r? compiler-errors
@rustbot author

[gurry]

@gurry: Please make sure to actually explain in your PR descriptions why something is happening and why your changes are correct, if it's not obvious from the title or the code itself. In this case, it's not really obvious

Sorry @compiler-errors. Have added the explanation in the description now.

[gurry]

@rustbot label -S-waiting-on-author +S-waiting-on-review

[compiler-errors]

@bors r+

[bors]

📌 Commit 446f78d has been approved by compiler-errors

It is now in the queue for this repository.

[bors]

⌛ Testing commit 446f78d with merge faefc61...

[bors]

☀️ Test successful - checks-actions
Approved by: compiler-errors
Pushing faefc61 to master...

[rust-timer]

Finished benchmarking commit (faefc61): comparison URL.

Overall result: no relevant changes - no action needed

@rustbot label: -perf-regression

Instruction count

This benchmark run did not return any relevant results for this metric.

Max RSS (memory usage)

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	4.6%	[4.6%, 4.6%]	1
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-1.2%	[-1.2%, -1.2%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	1.7%	[-1.2%, 4.6%]	2

Cycles

This benchmark run did not return any relevant results for this metric.

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 675.093s -> 677.065s (0.29%)
Artifact size: 315.94 MiB -> 315.85 MiB (-0.03%)