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Merged
merged 2 commits into from
Aug 9, 2025
Merged

Remove unneeded drop_in_place calls #144883

merged 2 commits into from
Aug 9, 2025
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scottmcm
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@scottmcm scottmcm commented Aug 4, 2025 •
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Might as well pull this out from #144561 because this is still used in things like Vec::truncate where it'd be nice to allow it be removed if inlined enough to see that the type is Copy.

So long as perf says it's ok, at least 🤞

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rustbot commented Aug 4, 2025

r? @nnethercote

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@rustbot rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels Aug 4, 2025
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rustbot commented Aug 4, 2025

Some changes occurred to MIR optimizations

cc @rust-lang/wg-mir-opt

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scottmcm commented Aug 4, 2025

@bors try @rust-timer queue

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rust-bors bot added a commit that referenced this pull request Aug 4, 2025
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Auto merge of #144883 - scottmcm:remove-unneeded-drop_in_place, r=<try>
641adcb 
Remove unneeded `drop_in_place` calls
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rust-bors bot commented Aug 4, 2025

⌛ Trying commit 952f142 with merge 641adcb…

To cancel the try build, run the command @bors try cancel.

@rustbot rustbot added the S-waiting-on-perf Status: Waiting on a perf run to be completed. label Aug 4, 2025
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rust-bors bot commented Aug 4, 2025

☀️ Try build successful (CI)
Build commit: 641adcb (641adcb8fe61a1a2f4cc317723476b9d171e2813, parent: 07b7dc90ee4df5815dbb91ef8e98cb93571230f5)

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Finished benchmarking commit (641adcb): comparison URL.

Overall result: no relevant changes - 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

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

Max RSS (memory usage)

Results (secondary -2.4%)

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)		 - - 0
Improvements ✅
(primary)		 - - 0
Improvements ✅
(secondary)		 -2.4% [-2.4%, -2.4%] 1
All ❌✅ (primary) - - 0

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: 467.146s -> 468.977s (0.39%)
Artifact size: 377.00 MiB -> 377.01 MiB (0.00%)

@rustbot rustbot removed the S-waiting-on-perf Status: Waiting on a perf run to be completed. label Aug 4, 2025
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Looks good. Feels like a brief explanatory comment mentioning the two cases would help, on the match. Or maybe the doc comment at the top of the file could be modified to mention the two cases?

r=me with that

@nnethercote nnethercote added S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Aug 5, 2025
@scottmcm scottmcm force-pushed the remove-unneeded-drop_in_place branch from 952f142 to 4e81eca Compare August 5, 2025 06:54
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@bors r+

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bors commented Aug 5, 2025

📌 Commit 4e81eca has been approved by nnethercote

It is now in the queue for this repository.

@bors bors 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-author Status: This is awaiting some action (such as code changes or more information) from the author. labels Aug 5, 2025
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scottmcm commented Aug 8, 2025

Looking at the size of the queue and the very quiet pre-merge perf results, I think I can downgrade this slightly to
@bors rollup=iffy

@Zalathar Zalathar mentioned this pull request Aug 9, 2025
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bors added a commit that referenced this pull request Aug 9, 2025
@bors
Auto merge of #145142 - Zalathar:rollup-oi6s8kg, r=Zalathar
f2aa3e0 
Rollup of 23 pull requests

Successful merges:

 - #141658 (rustdoc search: prefer stable items in search results)
 - #141828 (Add diagnostic explaining STATUS_STACK_BUFFER_OVERRUN not only being used for stack buffer overruns if link.exe exits with that exit code)
 - #144823 (coverage: Extract HIR-related helper code out of the main module)
 - #144883 (Remove unneeded `drop_in_place` calls)
 - #144923 (Move several more float tests to floats/mod.rs)
 - #144988 (Add annotations to the graphviz region graph on region origins)
 - #145010 (Couple of minor abi handling cleanups)
 - #145017 (Explicitly disable vector feature on s390x baseline of bad-reg test)
 - #145027 (Optimize `char::is_alphanumeric`)
 - #145050 (add member constraints tests)
 - #145073 (update enzyme submodule to handle llvm 21)
 - #145080 (Escape diff strings in MIR dataflow graphviz)
 - #145082 (Fix some bad formatting in `-Zmacro-stats` output.)
 - #145083 (Fix cross-compilation of Cargo)
 - #145096 (Fix wasm target build with atomics feature)
 - #145097 (remove unnecessary `TypeFoldable` impls)
 - #145100 (Rank doc aliases lower than equivalently matched items)
 - #145103 (rustc_metadata: remove unused private trait impls)
 - #145115 (defer opaque type errors, generally greatly reduce tainting)
 - #145119 (rustc_public: fix missing parenthesis in pretty discriminant)
 - #145124 (Recover `for PAT = EXPR {}`)
 - #145132 (Refactor map_unit_fn lint)
 - #145134 (Reduce indirect assoc parent queries)

r? `@ghost`
`@rustbot` modify labels: rollup
bors added a commit that referenced this pull request Aug 9, 2025
@bors
Auto merge of #145142 - Zalathar:rollup-oi6s8kg, r=Zalathar
ca77504 
Rollup of 23 pull requests

Successful merges:

 - #141658 (rustdoc search: prefer stable items in search results)
 - #141828 (Add diagnostic explaining STATUS_STACK_BUFFER_OVERRUN not only being used for stack buffer overruns if link.exe exits with that exit code)
 - #144823 (coverage: Extract HIR-related helper code out of the main module)
 - #144883 (Remove unneeded `drop_in_place` calls)
 - #144923 (Move several more float tests to floats/mod.rs)
 - #144988 (Add annotations to the graphviz region graph on region origins)
 - #145010 (Couple of minor abi handling cleanups)
 - #145017 (Explicitly disable vector feature on s390x baseline of bad-reg test)
 - #145027 (Optimize `char::is_alphanumeric`)
 - #145050 (add member constraints tests)
 - #145073 (update enzyme submodule to handle llvm 21)
 - #145080 (Escape diff strings in MIR dataflow graphviz)
 - #145082 (Fix some bad formatting in `-Zmacro-stats` output.)
 - #145083 (Fix cross-compilation of Cargo)
 - #145096 (Fix wasm target build with atomics feature)
 - #145097 (remove unnecessary `TypeFoldable` impls)
 - #145100 (Rank doc aliases lower than equivalently matched items)
 - #145103 (rustc_metadata: remove unused private trait impls)
 - #145115 (defer opaque type errors, generally greatly reduce tainting)
 - #145119 (rustc_public: fix missing parenthesis in pretty discriminant)
 - #145124 (Recover `for PAT = EXPR {}`)
 - #145132 (Refactor map_unit_fn lint)
 - #145134 (Reduce indirect assoc parent queries)

r? `@ghost`
`@rustbot` modify labels: rollup
@bors bors merged commit e63e769 into rust-lang:master Aug 9, 2025
10 checks passed
@rustbot rustbot added this to the 1.91.0 milestone Aug 9, 2025
rust-timer added a commit that referenced this pull request Aug 9, 2025
@rust-timer
Unrolled build for #144883
b8595e9 
Rollup merge of #144883 - scottmcm:remove-unneeded-drop_in_place, r=nnethercote

Remove unneeded `drop_in_place` calls

Might as well pull this out from #144561 because this is still used in things like `Vec::truncate` where it'd be nice to allow it be removed if inlined enough to see that the type is `Copy`.

So long as perf says it's ok, at least 🤞
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jieyouxu commented Aug 9, 2025

Hi bors this already merged
@bors r-

@bors bors added S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. and removed S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. labels Aug 9, 2025
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jieyouxu commented Aug 9, 2025

@rustbot label: -S-waiting-on-author +S-waiting-on-bors +merged-by-bors

@rustbot rustbot added merged-by-bors This PR was explicitly merged by bors. 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-author Status: This is awaiting some action (such as code changes or more information) from the author. labels Aug 9, 2025
@scottmcm scottmcm deleted the remove-unneeded-drop_in_place branch August 9, 2025 14:27
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