const-eval: do not make UbChecks behavior depend on current crate's flags

[RalfJung]

Fixes #129552

Let's see if we can get away with just always enabling these checks.

[rustbot]

r? @nnethercote

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[rustbot]

Some changes occurred to the CTFE / Miri engine

cc @rust-lang/miri

The Miri subtree was changed

cc @rust-lang/miri

[RalfJung]

r? @saethlin

@bors try
@rust-timer queue

[bors]

⌛ Trying commit d312fdc with merge b7fca3a...

[RalfJung]

@bors try

[bors]

⌛ Trying commit 7ea2981 with merge ed16544...

[bors]

☀️ Try build successful - checks-actions
Build commit: ed16544 (ed16544c35681a57b2a2f1a4fd440aeb7cd1bda2)

[rust-timer]

Finished benchmarking commit (ed16544): comparison URL.

Overall result: ❌ regressions - no action needed

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.

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

Instruction count

This is a highly reliable metric that was used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	2.3%	[2.3%, 2.3%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Max RSS (memory usage)

Results (primary -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)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-2.8%	[-2.8%, -2.8%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-2.8%	[-2.8%, -2.8%]	1

Cycles

Results (secondary 2.2%)

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)	-	-	0
Regressions ❌ (secondary)	2.2%	[2.2%, 2.2%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Binary size

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

Bootstrap: 752.172s -> 752.137s (-0.00%)
Artifact size: 338.71 MiB -> 338.77 MiB (0.02%)

[RalfJung]

Interesting, that's not even the ctfe stress test. It's also barely significant so I think we can ignore it.

[saethlin]

I'm not surprised we get away with no perf hit; unsafe const code is pretty rare to begin with.

And the one regression has a significance factor of 1.15x so there's a fair chance it's spurious.

@bors r+

[bors]

📌 Commit 7ea2981 has been approved by saethlin

It is now in the queue for this repository.

[bors]

⌛ Testing commit 7ea2981 with merge 9bc5ef2...

[rust-log-analyzer]

The job x86_64-msvc-ext failed! Check out the build log: (web) (plain)

Click to see the possible cause of the failure (guessed by this bot)

[RUSTC-TIMING] rustdoc test:false 58.011
[RUSTC-TIMING] rustdoc_tool_binary test:false 0.801
    Finished `release` profile [optimized] target(s) in 0.43s
thread 'main' panicked at src/lib.rs:1690:17:
failed to copy `C:\a\rust\rust\build\x86_64-pc-windows-msvc\stage0-tools\x86_64-pc-windows-msvc\release\rustdoc_tool_binary.exe` to `C:\a\rust\rust\build\x86_64-pc-windows-msvc\stage1\bin\rustdoc.exe`: The process cannot access the file because it is being used by another process. (os error 32)
##[endgroup]
Build completed unsuccessfully in 0:00:10
  local time: Wed, Aug 28, 2024 10:36:14 AM
  network time: Wed, 28 Aug 2024 10:36:15 GMT

[bors]

💔 Test failed - checks-actions

[RalfJung]

@bors retry failed to copy C:\a\rust\rust\build\x86_64-pc-windows-msvc\stage0-tools\x86_64-pc-windows-msvc\release\rustdoc_tool_binary.exe to C:\a\rust\rust\build\x86_64-pc-windows-msvc\stage1\bin\rustdoc.exe: The process cannot access the file because it is being used by another process. (os error 32)
Cc #127883

[saethlin]

@bors retry

[saethlin]

@bors rollup=iffy