Use the query vtable in query_feed plumbing

[Zalathar]

The query_feed function needs to be able to do two important things with (erased) query values: hash them, and debug-print them.

Both of those are things that the query's vtable already knows how to do. So by passing in a vtable to query_feed, we can give it a nicer signature, avoid having to unerase values in the function itself, and clean up some caller-side code as well.

[rustbot]

r? @jdonszelmann

rustbot has assigned @jdonszelmann.
They will have a look at your PR within the next two weeks and either review your PR or reassign to another reviewer.

Use r? to explicitly pick a reviewer

[Zalathar]

@bors try @rust-timer queue

[rustbot]

This PR was rebased onto a different main commit. Here's a range-diff highlighting what actually changed.

Rebasing is a normal part of keeping PRs up to date, so no action is needed—this note is just to help reviewers.

[Zalathar]

@bors try cancel

[rust-bors]

Try build cancelled. Cancelled workflows:

• https://github.com/rust-lang/rust/actions/runs/21509512327

[Zalathar]

@bors try

[rust-bors]

💥 Test timed out after 21600s

[lqd]

@bors try

[rust-bors]

☀️ Try build successful (CI)
Build commit: 7238d58 (7238d58d4d61ca7de1619789c4469d4dad134ec1, parent: e823167aa6f7f03aea8e91208ce9bace8ad9ebf2)

[rust-timer]

Finished benchmarking commit (7238d58): comparison URL.

Overall result: ❌✅ regressions and improvements - no action needed

Benchmarking this pull request means it may be perf-sensitive – we'll automatically label it not fit for rolling up. You can override this, but we strongly advise not to, due to possible changes in compiler perf.

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

Instruction count

Our most reliable metric. Used to determine the overall result above. However, even this metric can be noisy.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	0.2%	[0.0%, 0.3%]	4
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-0.1%	[-0.2%, -0.0%]	2
All ❌✅ (primary)	-	-	0

Max RSS (memory usage)

Results (primary -1.5%, secondary -0.3%)

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)	2.1%	[2.1%, 2.1%]	1
Improvements ✅ (primary)	-1.5%	[-2.1%, -0.9%]	2
Improvements ✅ (secondary)	-2.7%	[-2.7%, -2.7%]	1
All ❌✅ (primary)	-1.5%	[-2.1%, -0.9%]	2

Cycles

Results (secondary 0.6%)

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)	5.7%	[2.1%, 16.3%]	4
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-6.3%	[-6.6%, -5.9%]	3
All ❌✅ (primary)	-	-	0

Binary size

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

Bootstrap: 474.712s -> 474.274s (-0.09%)
Artifact size: 397.79 MiB -> 397.68 MiB (-0.03%)

[Zalathar]

Perf results look noisy/bimodal, nothing remarkable that I can see.

@rustbot ready

[jdonszelmann]

Not quite comfortable with the internals here, even though it looks correct. Maybe r? @oli-obk ? I think you worked on query feeding no?

[rustbot]

oli-obk is not on the review rotation at the moment.
They may take a while to respond.

[oli-obk]

Ah, wonderful. That's much better. I def wasn't looking at the larger picture, which I should have been doing

@bors r+

[rust-bors]

📌 Commit 09117c9 has been approved by oli-obk

It is now in the queue for this repository.

[rust-bors]

☀️ Test successful - CI
Approved by: oli-obk
Duration: 3h 40m 11s
Pushing 55407b8 to main...

[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 79a1e77 (parent) -> 55407b8 (this PR)

Test differences

Show 226 test diffs

226 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 55407b8cdb1457c62e0c852f5b53a9cf63ec4e1b --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-apple-various: 3869.2s -> 4722.3s (+22.0%)
2. aarch64-apple: 10874.0s -> 12793.2s (+17.6%)
3. dist-armv7-linux: 5101.5s -> 5785.6s (+13.4%)
4. x86_64-gnu-llvm-20-2: 6023.0s -> 5238.0s (-13.0%)
5. dist-arm-linux-gnueabi: 5019.9s -> 5557.5s (+10.7%)
6. aarch64-gnu-debug: 4315.3s -> 4632.6s (+7.4%)
7. i686-msvc-2: 7905.8s -> 7401.3s (-6.4%)
8. dist-aarch64-msvc: 5864.1s -> 6232.7s (+6.3%)
9. x86_64-gnu-aux: 8272.6s -> 7793.5s (-5.8%)
10. dist-powerpc-linux: 5247.4s -> 5536.0s (+5.5%)

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 (55407b8): 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 (primary -2.5%, secondary 1.3%)

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)	1.3%	[1.3%, 1.3%]	1
Improvements ✅ (primary)	-2.5%	[-2.8%, -1.8%]	3
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-2.5%	[-2.8%, -1.8%]	3

Cycles

Results (secondary 2.8%)

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)	2.8%	[2.8%, 2.8%]	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: 473.794s -> 471.991s (-0.38%)
Artifact size: 397.86 MiB -> 397.70 MiB (-0.04%)