Add specialization for deque1.prepend(deque2.drain(range)) (VecDeque::prepend and extend_front) - #150595

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antonilol:deque_extend_front_prepend_drain_spec
Jan 4, 2026
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Add specialization for deque1.prepend(deque2.drain(range)) (VecDeque::prepend and extend_front)#150595
bors merged 1 commit into
rust-lang:mainfrom
antonilol:deque_extend_front_prepend_drain_spec

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@antonilolantonilol commented Jan 2, 2026•
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Tracking issue: #146975

This specialization makes sure deque1.prepend(deque2.drain(..)) gets similar speed to deque1.append(&mut deque2). deque1.prepend(deque2.drain(..)) is the equivalent of deque1.append(&mut deque2) but appending to the front (see the second example of prepend, prepend is from the same tracking issue).

@rustbotrustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-libs Relevant to the library team, which will review and decide on the PR/issue. labels Jan 2, 2026
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@antonilol
antonilolforce-pushed the deque_extend_front_prepend_drain_spec branch from b8b94d7 to 887bb5aCompareJanuary 2, 2026 15:05
@antonilol
Add specialization for deque1.prepend(deque2.drain(range))
7e425b8
This is used when moving elements between `VecDeque`s
This pattern is also used in examples of `VecDeque::prepend`. (see its docs)
@antonilol
antonilolforce-pushed the deque_extend_front_prepend_drain_spec branch from 887bb5a to 7e425b8CompareJanuary 2, 2026 15:05
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📌 Commit 7e425b8 has been approved by jhpratt

It is now in the queue for this repository.

@borsbors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Jan 4, 2026
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⌛ Testing commit 7e425b8 with merge f280e76...

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☀️ Test successful - checks-actions
Approved by: jhpratt
Pushing f280e76 to main...

@borsbors added the merged-by-bors This PR was explicitly merged by bors. label Jan 4, 2026
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bors merged commit f280e76 into rust-lang:mainJan 4, 2026
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@rustbotrustbot added this to the 1.94.0 milestone Jan 4, 2026
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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 e25ee6b (parent) -> f280e76 (this PR)

Test differences

Show 4 test diffs

Stage 1

  • vec_deque::test_extend_front_specialization_deque_drain: [missing] -> pass (J0)

Stage 2

  • vec_deque::test_extend_front_specialization_deque_drain: [missing] -> pass (J1)

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

Job group index

Test dashboard

Run

cargo run --manifest-path src/ci/citool/Cargo.toml -- \
test-dashboard f280e764d51976d62da12033ddcbf72d0076a969 --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. pr-check-1: 2006.6s -> 1506.0s (-24.9%)
  2. aarch64-apple: 11262.2s -> 8644.7s (-23.2%)
  3. x86_64-gnu-debug: 7951.6s -> 6297.6s (-20.8%)
  4. x86_64-rust-for-linux: 3088.5s -> 2665.5s (-13.7%)
  5. aarch64-gnu-debug: 4711.8s -> 4113.3s (-12.7%)
  6. dist-powerpc-linux: 5115.8s -> 5650.6s (+10.5%)
  7. aarch64-gnu: 7232.1s -> 7977.3s (+10.3%)
  8. i686-gnu-1: 8242.4s -> 7423.0s (-9.9%)
  9. x86_64-gnu-miri: 4950.6s -> 4458.6s (-9.9%)
  10. dist-ohos-x86_64: 4214.6s -> 4620.1s (+9.6%)
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.

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Finished benchmarking commit (f280e76): 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

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: 473.697s -> 474.288s (0.12%)
Artifact size: 390.82 MiB -> 390.82 MiB (-0.00%)

@antonilol
antonilol deleted the deque_extend_front_prepend_drain_spec branch January 4, 2026 11:54
@github-actionsgithub-actionsBot mentioned this pull request Jan 27, 2026
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@antonilol@rustbot@jhpratt@bors@rust-timer
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
 blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

Skip to content
Add specialization for deque1.prepend(deque2.drain(range)) (VecDeque::prepend and extend_front) - #150595
Merged
bors merged 1 commit into
rust-lang:mainfrom 
antonilol:deque_extend_front_prepend_drain_spec
Jan 4, 2026
Merged
Add specialization for deque1.prepend(deque2.drain(range)) (VecDeque::prepend and extend_front)#150595
bors merged 1 commit into
rust-lang:mainfrom 
antonilol:deque_extend_front_prepend_drain_spec
Conversation
@antonilol
@antonilolantonilol
commented
Jan 2, 2026•

edited by rustbot

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Tracking issue: #146975
This specialization makes sure deque1.prepend(deque2.drain(..)) gets similar speed to deque1.append(&mut deque2). deque1.prepend(deque2.drain(..)) is the equivalent of deque1.append(&mut deque2) but appending to the front (see the second example of prepend, prepend is from the same tracking issue).
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Use r? to explicitly pick a reviewer
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@antonilol
antonilolforce-pushed
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deque_extend_front_prepend_drain_spec
branch
from
b8b94d7 to
887bb5aCompareJanuary 2, 2026 15:05
@antonilol
Add specialization for deque1.prepend(deque2.drain(range))
7e425b8
This is used when moving elements between `VecDeque`s
This pattern is also used in examples of `VecDeque::prepend`. (see its docs)
@antonilol
antonilolforce-pushed
the
deque_extend_front_prepend_drain_spec
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887bb5a to
7e425b8CompareJanuary 2, 2026 15:05
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📌 Commit 7e425b8 has been approved by jhpratt
It is now in the queue for this repository.
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Status: Waiting on bors to run and complete tests. Bors will change the label on completion.
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⌛ Testing commit 7e425b8 with merge f280e76...
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☀️ Test successful - checks-actions

Approved by: jhpratt

Pushing f280e76 to main...
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merged commit f280e76
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rust-lang:mainJan 4, 2026

12 checks passed

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added this to the 1.94.0 milestone
Jan 4, 2026
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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 e25ee6b (parent) -> f280e76 (this PR)
Test differences
Show 4 test diffs

Stage 1
  • vec_deque::test_extend_front_specialization_deque_drain: [missing] -> pass (J0)
Stage 2
  • vec_deque::test_extend_front_specialization_deque_drain: [missing] -> pass (J1)
Additionally, 2 doctest diffs were found. These are ignored, as they are noisy.
Job group index
Test dashboard
Run
cargo run --manifest-path src/ci/citool/Cargo.toml -- \
test-dashboard f280e764d51976d62da12033ddcbf72d0076a969 --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. pr-check-1: 2006.6s -> 1506.0s (-24.9%)
  2. aarch64-apple: 11262.2s -> 8644.7s (-23.2%)
  3. x86_64-gnu-debug: 7951.6s -> 6297.6s (-20.8%)
  4. x86_64-rust-for-linux: 3088.5s -> 2665.5s (-13.7%)
  5. aarch64-gnu-debug: 4711.8s -> 4113.3s (-12.7%)
  6. dist-powerpc-linux: 5115.8s -> 5650.6s (+10.5%)
  7. aarch64-gnu: 7232.1s -> 7977.3s (+10.3%)
  8. i686-gnu-1: 8242.4s -> 7423.0s (-9.9%)
  9. x86_64-gnu-miri: 4950.6s -> 4458.6s (-9.9%)
  10. dist-ohos-x86_64: 4214.6s -> 4620.1s (+9.6%)
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
rust-timer
commented
Jan 4, 2026

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Finished benchmarking commit (f280e76): 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
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: 473.697s -> 474.288s (0.12%)
Artifact size: 390.82 MiB -> 390.82 MiB (-0.00%)
@antonilol
antonilol
deleted the

deque_extend_front_prepend_drain_spec

branch
January 4, 2026 11:54
@github-actionsgithub-actionsBot
mentioned this pull request
Jan 27, 2026
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merged-by-borsThis PR was explicitly merged by bors.S-waiting-on-borsStatus: Waiting on bors to run and complete tests. Bors will change the label on completion.T-libsRelevant to the library team, which will review and decide on the PR/issue.

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1.94.0

Development

Successfully merging this pull request may close these issues.

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@antonilol@rustbot@jhpratt@bors@rust-timer

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
Add specialization for deque1.prepend(deque2.drain(range)) (VecDeque::prepend and extend_front) - #150595
Merged
bors merged 1 commit into
rust-lang:mainfrom 
antonilol:deque_extend_front_prepend_drain_spec
Jan 4, 2026
Merged
Add specialization for deque1.prepend(deque2.drain(range)) (VecDeque::prepend and extend_front)#150595
bors merged 1 commit into
rust-lang:mainfrom 
antonilol:deque_extend_front_prepend_drain_spec
Conversation
@antonilol
@antonilolantonilol
commented
Jan 2, 2026•

edited by rustbot

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Tracking issue: #146975
This specialization makes sure deque1.prepend(deque2.drain(..)) gets similar speed to deque1.append(&mut deque2). deque1.prepend(deque2.drain(..)) is the equivalent of deque1.append(&mut deque2) but appending to the front (see the second example of prepend, prepend is from the same tracking issue).
@rustbotrustbot
added

S-waiting-on-review
Status: Awaiting review from the assignee but also interested parties.
T-libs
Relevant to the library team, which will review and decide on the PR/issue.
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antonilolforce-pushed
the
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branch
from
b8b94d7 to
887bb5aCompareJanuary 2, 2026 15:05
@antonilol
Add specialization for deque1.prepend(deque2.drain(range))
7e425b8
This is used when moving elements between `VecDeque`s
This pattern is also used in examples of `VecDeque::prepend`. (see its docs)
@antonilol
antonilolforce-pushed
the
deque_extend_front_prepend_drain_spec
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887bb5a to
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📌 Commit 7e425b8 has been approved by jhpratt
It is now in the queue for this repository.
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added

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Status: Waiting on bors to run and complete tests. Bors will change the label on completion.
and removed

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⌛ Testing commit 7e425b8 with merge f280e76...
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☀️ Test successful - checks-actions

Approved by: jhpratt

Pushing f280e76 to main...
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merged commit f280e76
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added this to the 1.94.0 milestone
Jan 4, 2026
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Jan 4, 2026

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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 e25ee6b (parent) -> f280e76 (this PR)
Test differences
Show 4 test diffs

Stage 1
  • vec_deque::test_extend_front_specialization_deque_drain: [missing] -> pass (J0)
Stage 2
  • vec_deque::test_extend_front_specialization_deque_drain: [missing] -> pass (J1)
Additionally, 2 doctest diffs were found. These are ignored, as they are noisy.
Job group index
Test dashboard
Run
cargo run --manifest-path src/ci/citool/Cargo.toml -- \
test-dashboard f280e764d51976d62da12033ddcbf72d0076a969 --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. pr-check-1: 2006.6s -> 1506.0s (-24.9%)
  2. aarch64-apple: 11262.2s -> 8644.7s (-23.2%)
  3. x86_64-gnu-debug: 7951.6s -> 6297.6s (-20.8%)
  4. x86_64-rust-for-linux: 3088.5s -> 2665.5s (-13.7%)
  5. aarch64-gnu-debug: 4711.8s -> 4113.3s (-12.7%)
  6. dist-powerpc-linux: 5115.8s -> 5650.6s (+10.5%)
  7. aarch64-gnu: 7232.1s -> 7977.3s (+10.3%)
  8. i686-gnu-1: 8242.4s -> 7423.0s (-9.9%)
  9. x86_64-gnu-miri: 4950.6s -> 4458.6s (-9.9%)
  10. dist-ohos-x86_64: 4214.6s -> 4620.1s (+9.6%)
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
rust-timer
commented
Jan 4, 2026

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Finished benchmarking commit (f280e76): 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
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: 473.697s -> 474.288s (0.12%)
Artifact size: 390.82 MiB -> 390.82 MiB (-0.00%)
@antonilol
antonilol
deleted the

deque_extend_front_prepend_drain_spec

branch
January 4, 2026 11:54
@github-actionsgithub-actionsBot
mentioned this pull request
Jan 27, 2026
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Milestone

1.94.0

Development

Successfully merging this pull request may close these issues.

5 participants

@antonilol@rustbot@jhpratt@bors@rust-timer

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
Add specialization for deque1.prepend(deque2.drain(range)) (VecDeque::prepend and extend_front) - #150595
Merged
bors merged 1 commit into
rust-lang:mainfrom 
antonilol:deque_extend_front_prepend_drain_spec
Jan 4, 2026
Merged
Add specialization for deque1.prepend(deque2.drain(range)) (VecDeque::prepend and extend_front)#150595
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antonilol:deque_extend_front_prepend_drain_spec
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Jan 2, 2026•

edited by rustbot

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Tracking issue: #146975
This specialization makes sure deque1.prepend(deque2.drain(..)) gets similar speed to deque1.append(&mut deque2). deque1.prepend(deque2.drain(..)) is the equivalent of deque1.append(&mut deque2) but appending to the front (see the second example of prepend, prepend is from the same tracking issue).
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@antonilol
Add specialization for deque1.prepend(deque2.drain(range))
7e425b8
This is used when moving elements between `VecDeque`s
This pattern is also used in examples of `VecDeque::prepend`. (see its docs)
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📌 Commit 7e425b8 has been approved by jhpratt
It is now in the queue for this repository.
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⌛ Testing commit 7e425b8 with merge f280e76...
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☀️ Test successful - checks-actions

Approved by: jhpratt

Pushing f280e76 to main...
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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 e25ee6b (parent) -> f280e76 (this PR)
Test differences
Show 4 test diffs

Stage 1
  • vec_deque::test_extend_front_specialization_deque_drain: [missing] -> pass (J0)
Stage 2
  • vec_deque::test_extend_front_specialization_deque_drain: [missing] -> pass (J1)
Additionally, 2 doctest diffs were found. These are ignored, as they are noisy.
Job group index
Test dashboard
Run
cargo run --manifest-path src/ci/citool/Cargo.toml -- \
test-dashboard f280e764d51976d62da12033ddcbf72d0076a969 --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. pr-check-1: 2006.6s -> 1506.0s (-24.9%)
  2. aarch64-apple: 11262.2s -> 8644.7s (-23.2%)
  3. x86_64-gnu-debug: 7951.6s -> 6297.6s (-20.8%)
  4. x86_64-rust-for-linux: 3088.5s -> 2665.5s (-13.7%)
  5. aarch64-gnu-debug: 4711.8s -> 4113.3s (-12.7%)
  6. dist-powerpc-linux: 5115.8s -> 5650.6s (+10.5%)
  7. aarch64-gnu: 7232.1s -> 7977.3s (+10.3%)
  8. i686-gnu-1: 8242.4s -> 7423.0s (-9.9%)
  9. x86_64-gnu-miri: 4950.6s -> 4458.6s (-9.9%)
  10. dist-ohos-x86_64: 4214.6s -> 4620.1s (+9.6%)
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.
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Finished benchmarking commit (f280e76): 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
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: 473.697s -> 474.288s (0.12%)
Artifact size: 390.82 MiB -> 390.82 MiB (-0.00%)
@antonilol
antonilol
deleted the

deque_extend_front_prepend_drain_spec

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January 4, 2026 11:54
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

Skip to content
Add specialization for deque1.prepend(deque2.drain(range)) (VecDeque::prepend and extend_front) - #150595
Merged
bors merged 1 commit into
rust-lang:mainfrom 
antonilol:deque_extend_front_prepend_drain_spec
Jan 4, 2026
Merged
Add specialization for deque1.prepend(deque2.drain(range)) (VecDeque::prepend and extend_front)#150595
bors merged 1 commit into
rust-lang:mainfrom 
antonilol:deque_extend_front_prepend_drain_spec
Conversation
@antonilol
@antonilolantonilol
commented
Jan 2, 2026•

edited by rustbot

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Tracking issue: #146975
This specialization makes sure deque1.prepend(deque2.drain(..)) gets similar speed to deque1.append(&mut deque2). deque1.prepend(deque2.drain(..)) is the equivalent of deque1.append(&mut deque2) but appending to the front (see the second example of prepend, prepend is from the same tracking issue).
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labels
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antonilolforce-pushed
the
deque_extend_front_prepend_drain_spec
branch
from
b8b94d7 to
887bb5aCompareJanuary 2, 2026 15:05
@antonilol
Add specialization for deque1.prepend(deque2.drain(range))
7e425b8
This is used when moving elements between `VecDeque`s
This pattern is also used in examples of `VecDeque::prepend`. (see its docs)
@antonilol
antonilolforce-pushed
the
deque_extend_front_prepend_drain_spec
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887bb5a to
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📌 Commit 7e425b8 has been approved by jhpratt
It is now in the queue for this repository.
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⌛ Testing commit 7e425b8 with merge f280e76...
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☀️ Test successful - checks-actions

Approved by: jhpratt

Pushing f280e76 to main...
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added
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merged-by-bors
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@bors
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merged commit f280e76
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rust-lang:mainJan 4, 2026

12 checks passed

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added this to the 1.94.0 milestone
Jan 4, 2026
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Jan 4, 2026

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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 e25ee6b (parent) -> f280e76 (this PR)
Test differences
Show 4 test diffs

Stage 1
  • vec_deque::test_extend_front_specialization_deque_drain: [missing] -> pass (J0)
Stage 2
  • vec_deque::test_extend_front_specialization_deque_drain: [missing] -> pass (J1)
Additionally, 2 doctest diffs were found. These are ignored, as they are noisy.
Job group index
Test dashboard
Run
cargo run --manifest-path src/ci/citool/Cargo.toml -- \
test-dashboard f280e764d51976d62da12033ddcbf72d0076a969 --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. pr-check-1: 2006.6s -> 1506.0s (-24.9%)
  2. aarch64-apple: 11262.2s -> 8644.7s (-23.2%)
  3. x86_64-gnu-debug: 7951.6s -> 6297.6s (-20.8%)
  4. x86_64-rust-for-linux: 3088.5s -> 2665.5s (-13.7%)
  5. aarch64-gnu-debug: 4711.8s -> 4113.3s (-12.7%)
  6. dist-powerpc-linux: 5115.8s -> 5650.6s (+10.5%)
  7. aarch64-gnu: 7232.1s -> 7977.3s (+10.3%)
  8. i686-gnu-1: 8242.4s -> 7423.0s (-9.9%)
  9. x86_64-gnu-miri: 4950.6s -> 4458.6s (-9.9%)
  10. dist-ohos-x86_64: 4214.6s -> 4620.1s (+9.6%)
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
rust-timer
commented
Jan 4, 2026

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Finished benchmarking commit (f280e76): 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
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: 473.697s -> 474.288s (0.12%)
Artifact size: 390.82 MiB -> 390.82 MiB (-0.00%)
@antonilol
antonilol
deleted the

deque_extend_front_prepend_drain_spec

branch
January 4, 2026 11:54
@github-actionsgithub-actionsBot
mentioned this pull request
Jan 27, 2026
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Development

Successfully merging this pull request may close these issues.

5 participants

@antonilol@rustbot@jhpratt@bors@rust-timer

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
Add specialization for deque1.prepend(deque2.drain(range)) (VecDeque::prepend and extend_front) - #150595
Merged
bors merged 1 commit into
rust-lang:mainfrom 
antonilol:deque_extend_front_prepend_drain_spec
Jan 4, 2026
Merged
Add specialization for deque1.prepend(deque2.drain(range)) (VecDeque::prepend and extend_front)#150595
bors merged 1 commit into
rust-lang:mainfrom 
antonilol:deque_extend_front_prepend_drain_spec
Conversation
@antonilol
@antonilolantonilol
commented
Jan 2, 2026•

edited by rustbot

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Tracking issue: #146975
This specialization makes sure deque1.prepend(deque2.drain(..)) gets similar speed to deque1.append(&mut deque2). deque1.prepend(deque2.drain(..)) is the equivalent of deque1.append(&mut deque2) but appending to the front (see the second example of prepend, prepend is from the same tracking issue).
@rustbotrustbot
added

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Use r? to explicitly pick a reviewer
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mentioned this pull request
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@antonilol
antonilolforce-pushed
the
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branch
from
b8b94d7 to
887bb5aCompareJanuary 2, 2026 15:05
@antonilol
Add specialization for deque1.prepend(deque2.drain(range))
7e425b8
This is used when moving elements between `VecDeque`s
This pattern is also used in examples of `VecDeque::prepend`. (see its docs)
@antonilol
antonilolforce-pushed
the
deque_extend_front_prepend_drain_spec
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887bb5a to
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📌 Commit 7e425b8 has been approved by jhpratt
It is now in the queue for this repository.
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added

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⌛ Testing commit 7e425b8 with merge f280e76...
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☀️ Test successful - checks-actions

Approved by: jhpratt

Pushing f280e76 to main...
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@bors
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merged commit f280e76
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12 checks passed

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added this to the 1.94.0 milestone
Jan 4, 2026
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Jan 4, 2026

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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 e25ee6b (parent) -> f280e76 (this PR)
Test differences
Show 4 test diffs

Stage 1
  • vec_deque::test_extend_front_specialization_deque_drain: [missing] -> pass (J0)
Stage 2
  • vec_deque::test_extend_front_specialization_deque_drain: [missing] -> pass (J1)
Additionally, 2 doctest diffs were found. These are ignored, as they are noisy.
Job group index
Test dashboard
Run
cargo run --manifest-path src/ci/citool/Cargo.toml -- \
test-dashboard f280e764d51976d62da12033ddcbf72d0076a969 --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. pr-check-1: 2006.6s -> 1506.0s (-24.9%)
  2. aarch64-apple: 11262.2s -> 8644.7s (-23.2%)
  3. x86_64-gnu-debug: 7951.6s -> 6297.6s (-20.8%)
  4. x86_64-rust-for-linux: 3088.5s -> 2665.5s (-13.7%)
  5. aarch64-gnu-debug: 4711.8s -> 4113.3s (-12.7%)
  6. dist-powerpc-linux: 5115.8s -> 5650.6s (+10.5%)
  7. aarch64-gnu: 7232.1s -> 7977.3s (+10.3%)
  8. i686-gnu-1: 8242.4s -> 7423.0s (-9.9%)
  9. x86_64-gnu-miri: 4950.6s -> 4458.6s (-9.9%)
  10. dist-ohos-x86_64: 4214.6s -> 4620.1s (+9.6%)
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
rust-timer
commented
Jan 4, 2026

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Finished benchmarking commit (f280e76): 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
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: 473.697s -> 474.288s (0.12%)
Artifact size: 390.82 MiB -> 390.82 MiB (-0.00%)
@antonilol
antonilol
deleted the

deque_extend_front_prepend_drain_spec

branch
January 4, 2026 11:54
@github-actionsgithub-actionsBot
mentioned this pull request
Jan 27, 2026
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Milestone

1.94.0

Development

Successfully merging this pull request may close these issues.

5 participants

@antonilol@rustbot@jhpratt@bors@rust-timer

, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
Add specialization for deque1.prepend(deque2.drain(range)) (VecDeque::prepend and extend_front) - #150595
Merged
bors merged 1 commit into
rust-lang:mainfrom 
antonilol:deque_extend_front_prepend_drain_spec
Jan 4, 2026
Merged
Add specialization for deque1.prepend(deque2.drain(range)) (VecDeque::prepend and extend_front)#150595
bors merged 1 commit into
rust-lang:mainfrom 
antonilol:deque_extend_front_prepend_drain_spec
Conversation
@antonilol
@antonilolantonilol
commented
Jan 2, 2026•

edited by rustbot

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Tracking issue: #146975
This specialization makes sure deque1.prepend(deque2.drain(..)) gets similar speed to deque1.append(&mut deque2). deque1.prepend(deque2.drain(..)) is the equivalent of deque1.append(&mut deque2) but appending to the front (see the second example of prepend, prepend is from the same tracking issue).
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Add specialization for deque1.prepend(deque2.drain(range))
7e425b8
This is used when moving elements between `VecDeque`s
This pattern is also used in examples of `VecDeque::prepend`. (see its docs)
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📌 Commit 7e425b8 has been approved by jhpratt
It is now in the queue for this repository.
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⌛ Testing commit 7e425b8 with merge f280e76...
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☀️ Test successful - checks-actions

Approved by: jhpratt

Pushing f280e76 to main...
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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 e25ee6b (parent) -> f280e76 (this PR)
Test differences
Show 4 test diffs

Stage 1
  • vec_deque::test_extend_front_specialization_deque_drain: [missing] -> pass (J0)
Stage 2
  • vec_deque::test_extend_front_specialization_deque_drain: [missing] -> pass (J1)
Additionally, 2 doctest diffs were found. These are ignored, as they are noisy.
Job group index
Test dashboard
Run
cargo run --manifest-path src/ci/citool/Cargo.toml -- \
test-dashboard f280e764d51976d62da12033ddcbf72d0076a969 --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. pr-check-1: 2006.6s -> 1506.0s (-24.9%)
  2. aarch64-apple: 11262.2s -> 8644.7s (-23.2%)
  3. x86_64-gnu-debug: 7951.6s -> 6297.6s (-20.8%)
  4. x86_64-rust-for-linux: 3088.5s -> 2665.5s (-13.7%)
  5. aarch64-gnu-debug: 4711.8s -> 4113.3s (-12.7%)
  6. dist-powerpc-linux: 5115.8s -> 5650.6s (+10.5%)
  7. aarch64-gnu: 7232.1s -> 7977.3s (+10.3%)
  8. i686-gnu-1: 8242.4s -> 7423.0s (-9.9%)
  9. x86_64-gnu-miri: 4950.6s -> 4458.6s (-9.9%)
  10. dist-ohos-x86_64: 4214.6s -> 4620.1s (+9.6%)
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.
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Finished benchmarking commit (f280e76): 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
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: 473.697s -> 474.288s (0.12%)
Artifact size: 390.82 MiB -> 390.82 MiB (-0.00%)
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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Add specialization for deque1.prepend(deque2.drain(range)) (VecDeque::prepend and extend_front) - #150595
Merged
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antonilol:deque_extend_front_prepend_drain_spec
Jan 4, 2026
Merged
Add specialization for deque1.prepend(deque2.drain(range)) (VecDeque::prepend and extend_front)#150595
bors merged 1 commit into
rust-lang:mainfrom 
antonilol:deque_extend_front_prepend_drain_spec
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Jan 2, 2026•

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Tracking issue: #146975
This specialization makes sure deque1.prepend(deque2.drain(..)) gets similar speed to deque1.append(&mut deque2). deque1.prepend(deque2.drain(..)) is the equivalent of deque1.append(&mut deque2) but appending to the front (see the second example of prepend, prepend is from the same tracking issue).
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antonilolforce-pushed
the
deque_extend_front_prepend_drain_spec
branch
from
b8b94d7 to
887bb5aCompareJanuary 2, 2026 15:05
@antonilol
Add specialization for deque1.prepend(deque2.drain(range))
7e425b8
This is used when moving elements between `VecDeque`s
This pattern is also used in examples of `VecDeque::prepend`. (see its docs)
@antonilol
antonilolforce-pushed
the
deque_extend_front_prepend_drain_spec
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887bb5a to
7e425b8CompareJanuary 2, 2026 15:05
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📌 Commit 7e425b8 has been approved by jhpratt
It is now in the queue for this repository.
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⌛ Testing commit 7e425b8 with merge f280e76...
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☀️ Test successful - checks-actions

Approved by: jhpratt

Pushing f280e76 to main...
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@bors
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merged commit f280e76
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12 checks passed

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added this to the 1.94.0 milestone
Jan 4, 2026
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Jan 4, 2026

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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 e25ee6b (parent) -> f280e76 (this PR)
Test differences
Show 4 test diffs

Stage 1
  • vec_deque::test_extend_front_specialization_deque_drain: [missing] -> pass (J0)
Stage 2
  • vec_deque::test_extend_front_specialization_deque_drain: [missing] -> pass (J1)
Additionally, 2 doctest diffs were found. These are ignored, as they are noisy.
Job group index
Test dashboard
Run
cargo run --manifest-path src/ci/citool/Cargo.toml -- \
test-dashboard f280e764d51976d62da12033ddcbf72d0076a969 --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. pr-check-1: 2006.6s -> 1506.0s (-24.9%)
  2. aarch64-apple: 11262.2s -> 8644.7s (-23.2%)
  3. x86_64-gnu-debug: 7951.6s -> 6297.6s (-20.8%)
  4. x86_64-rust-for-linux: 3088.5s -> 2665.5s (-13.7%)
  5. aarch64-gnu-debug: 4711.8s -> 4113.3s (-12.7%)
  6. dist-powerpc-linux: 5115.8s -> 5650.6s (+10.5%)
  7. aarch64-gnu: 7232.1s -> 7977.3s (+10.3%)
  8. i686-gnu-1: 8242.4s -> 7423.0s (-9.9%)
  9. x86_64-gnu-miri: 4950.6s -> 4458.6s (-9.9%)
  10. dist-ohos-x86_64: 4214.6s -> 4620.1s (+9.6%)
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
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commented
Jan 4, 2026

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Finished benchmarking commit (f280e76): 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
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: 473.697s -> 474.288s (0.12%)
Artifact size: 390.82 MiB -> 390.82 MiB (-0.00%)
@antonilol
antonilol
deleted the

deque_extend_front_prepend_drain_spec

branch
January 4, 2026 11:54
@github-actionsgithub-actionsBot
mentioned this pull request
Jan 27, 2026
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