Unconditionally check sizedness of body in typeck to taint typeck results

[compiler-errors]

Puts the sized check back into typeck (duplicated -- we still have it in wfcheck) so that we properly taint bodies. These duplicated diagnostics will all be deduplicated with -Zdeduplicate-diagnostics, so it's just UI test fallout and not an actual regression in user-facing diagnostics.

We could perhaps do this without duplicating all the diagnostics if we put this check into something like mir build 🤔 Ideally CTFE would just be more fallible to non-WF code but 🤷

Fixes #137186

[rustbot]

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[compiler-errors]

r? lcnr, perhaps?

[lcnr]

r=me on the changes itself and think its fine to merge this 👍

I feel a bit unhappy with approach, both for its doing unnecessary work, but also because I feel like there's a more general fix which would likely be useful going forward.

We currently taint the MIR in mir_drops_elaborated_and_const_checked

rust/compiler/rustc_mir_transform/src/lib.rs

Lines 512 to 514 in 5986ff0

	if let Some(error_reported) = tainted_by_errors {
	body.tainted_by_errors = Some(error_reported);
	}

If we also check check_well_formed for the item here, do we use this tainted_by_errors to disable CTFE? and if not, we probably should

@bors try @rust-timer queue

[bors]

⌛ Trying commit a0dbaf2 with merge 9183270...

[bors]

☀️ Try build successful - checks-actions
Build commit: 9183270 (918327092fd732f66cf417d90bc3ae2551e7c44b)

[rust-timer]

Finished benchmarking commit (9183270): comparison URL.

Overall result: ❌✅ regressions and improvements - please read the text below

Benchmarking this pull request likely means that it is perf-sensitive, so we're automatically marking it as not fit for rolling up. While you can manually mark this PR as fit for rollup, we strongly recommend not doing so since this PR may lead to changes in compiler perf.

Next Steps: If you can justify the regressions found in this try perf run, please indicate this with @rustbot label: +perf-regression-triaged along with sufficient written justification. If you cannot justify the regressions please fix the regressions and do another perf run. If the next run shows neutral or positive results, the label will be automatically removed.

@bors rollup=never
@rustbot label: -S-waiting-on-perf +perf-regression

Instruction count

This is the most reliable metric that we have; it was used to determine the overall result at the top of this comment. However, even this metric can sometimes exhibit noise.

	mean	range	count
Regressions ❌ (primary)	0.3%	[0.2%, 0.3%]	10
Regressions ❌ (secondary)	0.2%	[0.2%, 0.2%]	2
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-0.0%	[-0.0%, -0.0%]	1
All ❌✅ (primary)	0.3%	[0.2%, 0.3%]	10

Max RSS (memory usage)

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

Cycles

Results (primary 3.8%, secondary 2.8%)

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)	3.8%	[3.8%, 3.8%]	1
Regressions ❌ (secondary)	2.8%	[2.1%, 4.0%]	8
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	3.8%	[3.8%, 3.8%]	1

Binary size

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

Bootstrap: 773.598s -> 774.943s (0.17%)
Artifact size: 360.32 MiB -> 360.32 MiB (0.00%)

[compiler-errors]

#137298