Update memchr to 2.7.6

[neuschaefer]

memchr 2.7.6 contains a bugfix for aarch64_be.

Note: I'm not sure about how dependency updates are managed in rust.git. If something should go through another branch or will happen automatically, please let me know.

[rustbot]

These commits modify the Cargo.lock file. Unintentional changes to Cargo.lock can be introduced when switching branches and rebasing PRs.

If this was unintentional then you should revert the changes before this PR is merged.
Otherwise, you can ignore this comment.

The Miri subtree was changed

cc @rust-lang/miri

These commits modify the library/Cargo.lock file. Unintentional changes to library/Cargo.lock can be introduced when switching branches and rebasing PRs.

If this was unintentional then you should revert the changes before this PR is merged.
Otherwise, you can ignore this comment.

stdarch is developed in its own repository. If possible, consider making this change to rust-lang/stdarch instead.

cc @Amanieu, @folkertdev, @sayantn

rust-analyzer is developed in its own repository. If possible, consider making this change to rust-lang/rust-analyzer instead.

cc @rust-lang/rust-analyzer

[rustbot]

r? @marcoieni

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Use r? to explicitly pick a reviewer

[lnicola]

If it's not urgent, please file the r-a change upstream, to avoid Cargo.lock conflicts.

[folkertdev]

For stdarch updating either here or in the repo is fine, though yeah for Cargo.lock conflicts updating in the repo itself is probably cleaner given that stdarch should only use memchr for tests.

The issue that is fixed in BurntSushi/memchr#188 reminds me of rust-lang/stdarch#1904 where we're also seeing some confusing behavior on aarch64_be, but we're not quite sure yet what the problem is given that currently our tests do pass with what we believe is an incorrect implementation.

[neuschaefer]

Alright, I'll go through the respective trees for rust-analyzer and stdarch.

rust-lang/stdarch#1904 is interesting, I only became aware of it today. I'll keep watching it to see which decision is made, and how it might make the change in memchr 2.7.6 invalid after all.

[marcoieni]

Sorry it took so long!

@bors r+

[bors]

📌 Commit 5a3b82b has been approved by marcoieni

It is now in the queue for this repository.

[bors]

⌛ Testing commit 5a3b82b with merge a3fdaee...

[bors]

💔 Test failed - checks-actions

[saethlin]

@bors retry

[rust-log-analyzer]

The job tidy failed! Check out the build log: (web) (plain enhanced) (plain)

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

spellchecking files
building external tool typos from package [email protected]
finished building tool typos
npm WARN deprecated [email protected]: < 24.10.2 is no longer supported
npm ERR! code 127
npm ERR! git dep preparation failed
npm ERR! command /node/bin/node /node/lib/node_modules/npm/bin/npm-cli.js install --force --cache=/home/user/.npm --prefer-offline=false --prefer-online=false --offline=false --no-progress --no-save --no-audit --include=dev --include=peer --include=optional --no-package-lock-only --no-dry-run
npm ERR! npm WARN using --force Recommended protections disabled.
npm ERR! npm WARN deprecated [email protected]: This module is not supported, and leaks memory. Do not use it. Check out lru-cache if you want a good and tested way to coalesce async requests by a key value, which is much more comprehensive and powerful.
npm ERR! npm WARN deprecated [email protected]: Glob versions prior to v9 are no longer supported
npm ERR! npm WARN deprecated [email protected]: Glob versions prior to v9 are no longer supported
npm ERR! npm WARN deprecated [email protected]: Package no longer supported. Contact Support at https://www.npmjs.com/support for more info.
npm ERR! npm WARN deprecated [email protected]: This functionality has been moved to @npmcli/fs
npm ERR! npm WARN deprecated [email protected]: This package is no longer supported. Please use @npmcli/package-json instead.
npm ERR! npm WARN deprecated [email protected]: This package is no longer supported.
npm ERR! npm ERR! code 127
npm ERR! npm ERR! path /home/user/.npm/_cacache/tmp/git-cloneXXXXXXl7RCTT/node_modules/rollup
npm ERR! npm ERR! command failed
npm ERR! npm ERR! command sh -c patch-package
npm ERR! npm ERR! sh: 1: patch-package: not found
npm ERR! 
npm ERR! npm ERR! A complete log of this run can be found in: /home/user/.npm/_logs/2025-11-07T18_23_01_456Z-debug-0.log

npm ERR! A complete log of this run can be found in: /home/user/.npm/_logs/2025-11-07T18_22_54_043Z-debug-0.log
npm install did not exit successfully
tidy [extra_checks]: IO error: npm install returned exit code exit status: 127
tidy [extra_checks]: FAIL
tidy: The following check failed: extra_checks
Bootstrap failed while executing `test src/tools/tidy tidyselftest --extra-checks=py,cpp,js,spellcheck`
Command `/checkout/obj/build/x86_64-unknown-linux-gnu/stage1-tools-bin/rust-tidy /checkout /checkout/obj/build/x86_64-unknown-linux-gnu/stage0/bin/cargo /checkout/obj/build 4 /node/bin/npm --extra-checks=py,cpp,js,spellcheck` failed with exit code 1
Created at: src/bootstrap/src/core/build_steps/tool.rs:1549:23
Executed at: src/bootstrap/src/core/build_steps/test.rs:1279:29

Command has failed. Rerun with -v to see more details.
Build completed unsuccessfully in 0:03:29
  local time: Fri Nov  7 18:23:25 UTC 2025
  network time: Fri, 07 Nov 2025 18:23:25 GMT
##[error]Process completed with exit code 1.
##[group]Run echo "disk usage:"

[bors]

⌛ Testing commit 5a3b82b with merge ceb7df7...

[bors]

☀️ Test successful - checks-actions
Approved by: marcoieni
Pushing ceb7df7 to master...

[github-actions]

What is this?

This is an experimental post-merge analysis report that shows differences in test outcomes between the merged PR and its parent PR.

Comparing 843f8ce (parent) -> ceb7df7 (this PR)

Test differences

Show 2 test diffs

2 doctest diffs were found. These are ignored, as they are noisy.

Test dashboard

Run

cargo run --manifest-path src/ci/citool/Cargo.toml -- \
    test-dashboard ceb7df7e6f17c92c7d49f7e4f02df0e68bc9b38b --output-dir test-dashboard

And then open test-dashboard/index.html in your browser to see an overview of all executed tests.

Job duration changes

1. dist-x86_64-apple: 8954.3s -> 5730.7s (-36.0%)
2. aarch64-apple: 9064.1s -> 7051.7s (-22.2%)
3. i686-gnu-2: 5099.1s -> 6186.8s (+21.3%)
4. x86_64-gnu-llvm-21-1: 3226.1s -> 3889.5s (+20.6%)
5. x86_64-gnu-llvm-20: 2414.1s -> 2881.1s (+19.3%)
6. aarch64-gnu-debug: 3763.0s -> 4441.5s (+18.0%)
7. x86_64-rust-for-linux: 2627.3s -> 3030.3s (+15.3%)
8. arm-android: 5474.2s -> 6301.6s (+15.1%)
9. dist-aarch64-apple: 7815.0s -> 6727.2s (-13.9%)
10. dist-ohos-aarch64: 4633.4s -> 4036.8s (-12.9%)

How to interpret the job duration changes?

Job durations can vary a lot, based on the actual runner instance
that executed the job, system noise, invalidated caches, etc. The table above is provided
mostly for t-infra members, for simpler debugging of potential CI slow-downs.

[rust-timer]

Finished benchmarking commit (ceb7df7): 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)

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

Cycles

Results (secondary -1.0%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	3.3%	[3.3%, 3.3%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-5.3%	[-5.3%, -5.3%]	1
All ❌✅ (primary)	-	-	0

Binary size

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

Bootstrap: 483.325s -> 475.105s (-1.70%)
Artifact size: 390.81 MiB -> 390.80 MiB (-0.00%)