In Option::get_or_insert_with(), forget the None instead of dropping it. - #148562

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In Option::get_or_insert_with(), forget the None instead of dropping it.#148562
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kpreid:get-init-drop

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Per #148486 (comment)

In Option::get_or_insert_with(), after replacing the None with Some, forget the None instead of dropping it.

This allows eliminating the T: [const] Destruct bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit drop_in_place::<Option<T>>() that will never do anything (and which might even persist after optimization).

@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 Nov 6, 2025
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r? @ibraheemdev

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cc @cyb0124 (this change is based on their idea)

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Comment threadlibrary/coretests/tests/option.rs Outdated
Comment threadlibrary/core/src/option.rs Outdated
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Thanks! Looks good to me.

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clarfonthey
clarfonthey reviewed Nov 23, 2025
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Comment threadlibrary/core/src/option.rs Outdated
@kpreid
In Option::get_or_insert_with(), forget the None instead of dropp…
c1b51dd
…ing it.
This allows eliminating the `T: [const] Destruct` bounds and avoids
generating an implicit `drop_in_place::<Option<T>>()` that will never do
anything.
Ideally, the compiler would prove that that drop is not necessary
itself, but it currently doesn't, even with `const_precise_live_drops`
enabled.
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The implementation looks good to me. r? libs-api for the unstable API change.

@rustbotrustbot added the T-libs-api [DEPRECATED; DO NOT USE] label Feb 9, 2026
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Per advice:

@rustbot label -S-waiting-on-review +S-waiting-on-t-libs-api

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Error: Unknown labels: S-waiting-on-libs-api

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@rustbotrustbot added S-waiting-on-t-libs-api [DEPRECATED; DO NOT USE] and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Mar 9, 2026
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Can you check the final optimized runtime MIR before and after your change? I'm not sure we're optimizing the new code properly.

Also wondering about this pattern in general. Seems like sth const precise live drops could also handle, haven't looked at that in forever so I don't remember the details of it.

Anyway, if the final runtime MIR looks good, let's merge this

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Can you check the final optimized runtime MIR before and after your change? I'm not sure we're optimizing the new code properly.

I’m not familiar with how to do that, but I will look into it.

Seems like sth const precise live drops could also handle,

See prior discussion #148562 (comment) — in brief, having const_precise_live_drops would mean we are having the compiler doing static checking on how control flow affects values (whether the option is None), which is something that we generally only do for lint (e.g. if false {} is not counted as unreachable code).

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oli-obk and I have looked at the MIR through dropping both implementations into Compiler Explorer and it seems generally similar, but also not very optimized either before or after.

@rustbot label +const-hack

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Error: Unknown labels: const-hack

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@bors r+ rollup

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📋 This PR cannot be approved because it currently has the following label: S-waiting-on-t-libs-api.

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Auto merge of#148562- kpreid:get-init-drop, r=oli-obk
e7bce32
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
matthiaskrgr added a commit to matthiaskrgr/rust that referenced this pull request Mar 9, 2026
@matthiaskrgr
Rollup merge ofrust-lang#148562- kpreid:get-init-drop, r=oli-obk
cef2175
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per rust-lang#148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
@matthiaskrgrmatthiaskrgr mentioned this pull request Mar 9, 2026
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Auto build was cancelled. Cancelled workflows:

The next pull request likely to be tested is #153628.

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Auto merge of#153628- matthiaskrgr:rollup-V2cZQof, r=matthiaskrgr
6802080
Rollup of 8 pull requests
Successful merges:
- #148562 (In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.)
- #149931 (rustdoc: don't give depreciation notes special handling)
- #153608 (ast_passes: unsupported arch w/ scalable vectors)
- #153609 (Add missing `Diag::with_span_suggestion_with_style` method)
- #153610 (Only lint unused features if they are unstable)
- #153616 (Update `sysinfo` version to `0.38.4`)
- #153619 (Update books)
- #153624 (Ping fmease on parser modifications)
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Auto merge of#148562- kpreid:get-init-drop, r=oli-obk
50c1062
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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The dist-x86_64-linux job is stuck.

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Auto build was cancelled. Cancelled workflows:

The next pull request likely to be tested is #153631.

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Auto merge of#153642- matthiaskrgr:rollup-IHw8KqK, r=matthiaskrgr
2254b92
Rollup of 4 pull requests
Successful merges:
- #148562 (In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.)
- #153325 (tests/ui/cfg: add annotations for reference rules)
- #153621 (Remove `TyCtxt::node_span_lint` method)
- #153627 (rustdoc-json: Improve docs for `ItemEnum::item_kind`)
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Auto merge of#148562- kpreid:get-init-drop, r=oli-obk
8744ff0
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
@rust-borsrust-borsBot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. and removed S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. labels Mar 10, 2026
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💔 Test for 8744ff0 failed: CI. Failed job:

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@bors retry (network failure)

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Auto merge of#153642- matthiaskrgr:rollup-IHw8KqK, r=matthiaskrgr
5c216d1
Rollup of 4 pull requests
Successful merges:
- #148562 (In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.)
- #153325 (tests/ui/cfg: add annotations for reference rules)
- #153621 (Remove `TyCtxt::node_span_lint` method)
- #153627 (rustdoc-json: Improve docs for `ItemEnum::item_kind`)
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rust-borsBot pushed a commit that referenced this pull request Mar 10, 2026
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Auto merge of#153642- matthiaskrgr:rollup-IHw8KqK, r=matthiaskrgr
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Rollup of 4 pull requests
Successful merges:
- #148562 (In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.)
- #153325 (tests/ui/cfg: add annotations for reference rules)
- #153621 (Remove `TyCtxt::node_span_lint` method)
- #153627 (rustdoc-json: Improve docs for `ItemEnum::item_kind`)
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Unrolled build for#148562
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Rollup merge of #148562 - kpreid:get-init-drop, r=oli-obk
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
@kpreid
kpreid deleted the get-init-drop branch March 10, 2026 20:40
flip1995 pushed a commit to flip1995/rust-clippy that referenced this pull request Aug 17, 2026
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Auto merge of #153642 - matthiaskrgr:rollup-IHw8KqK, r=matthiaskrgr
88640a4
Rollup of 4 pull requests
Successful merges:
- rust-lang/rust#148562 (In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.)
- rust-lang/rust#153325 (tests/ui/cfg: add annotations for reference rules)
- rust-lang/rust#153621 (Remove `TyCtxt::node_span_lint` method)
- rust-lang/rust#153627 (rustdoc-json: Improve docs for `ItemEnum::item_kind`)
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In Option::get_or_insert_with(), forget the None instead of dropping it. - #148562
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In Option::get_or_insert_with(), forget the None instead of dropping it.#148562
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Per #148486 (comment)
In Option::get_or_insert_with(), after replacing the None with Some, forget the None instead of dropping it.
This allows eliminating the T: [const] Destruct bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit drop_in_place::<Option<T>>() that will never do anything (and which might even persist after optimization).
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r? @ibraheemdev
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cc @cyb0124 (this change is based on their idea)
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Comment threadlibrary/coretests/tests/option.rs
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Thanks! Looks good to me.
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Comment threadlibrary/core/src/option.rs
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@kpreid
In Option::get_or_insert_with(), forget the None instead of dropp…
c1b51dd
…ing it.
This allows eliminating the `T: [const] Destruct` bounds and avoids
generating an implicit `drop_in_place::<Option<T>>()` that will never do
anything.
Ideally, the compiler would prove that that drop is not necessary
itself, but it currently doesn't, even with `const_precise_live_drops`
enabled.
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The implementation looks good to me. r? libs-api for the unstable API change.
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Per advice:
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Can you check the final optimized runtime MIR before and after your change? I'm not sure we're optimizing the new code properly.
Also wondering about this pattern in general. Seems like sth const precise live drops could also handle, haven't looked at that in forever so I don't remember the details of it.
Anyway, if the final runtime MIR looks good, let's merge this
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Can you check the final optimized runtime MIR before and after your change? I'm not sure we're optimizing the new code properly.
I’m not familiar with how to do that, but I will look into it.
Seems like sth const precise live drops could also handle,
See prior discussion #148562 (comment) — in brief, having const_precise_live_drops would mean we are having the compiler doing static checking on how control flow affects values (whether the option is None), which is something that we generally only do for lint (e.g. if false {} is not counted as unreachable code).
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oli-obk and I have looked at the MIR through dropping both implementations into Compiler Explorer and it seems generally similar, but also not very optimized either before or after.
@rustbot label +const-hack
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Error: Unknown labels: const-hack
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@bors r+ rollup
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📋 This PR cannot be approved because it currently has the following label: S-waiting-on-t-libs-api.
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Auto merge of#148562- kpreid:get-init-drop, r=oli-obk
e7bce32
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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Rollup merge ofrust-lang#148562- kpreid:get-init-drop, r=oli-obk
cef2175
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per rust-lang#148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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Auto build was cancelled. Cancelled workflows:
The next pull request likely to be tested is #153628.
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Auto merge of#153628- matthiaskrgr:rollup-V2cZQof, r=matthiaskrgr
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Rollup of 8 pull requests
Successful merges:
- #148562 (In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.)
- #149931 (rustdoc: don't give depreciation notes special handling)
- #153608 (ast_passes: unsupported arch w/ scalable vectors)
- #153609 (Add missing `Diag::with_span_suggestion_with_style` method)
- #153610 (Only lint unused features if they are unstable)
- #153616 (Update `sysinfo` version to `0.38.4`)
- #153619 (Update books)
- #153624 (Ping fmease on parser modifications)
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In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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- #153325 (tests/ui/cfg: add annotations for reference rules)
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Rollup merge of #148562 - kpreid:get-init-drop, r=oli-obk
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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Auto merge of #153642 - matthiaskrgr:rollup-IHw8KqK, r=matthiaskrgr
88640a4
Rollup of 4 pull requests
Successful merges:
- rust-lang/rust#148562 (In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.)
- rust-lang/rust#153325 (tests/ui/cfg: add annotations for reference rules)
- rust-lang/rust#153621 (Remove `TyCtxt::node_span_lint` method)
- rust-lang/rust#153627 (rustdoc-json: Improve docs for `ItemEnum::item_kind`)
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In Option::get_or_insert_with(), forget the None instead of dropping it. - #148562
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In Option::get_or_insert_with(), forget the None instead of dropping it.#148562
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Per #148486 (comment)
In Option::get_or_insert_with(), after replacing the None with Some, forget the None instead of dropping it.
This allows eliminating the T: [const] Destruct bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit drop_in_place::<Option<T>>() that will never do anything (and which might even persist after optimization).
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r? @ibraheemdev
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cc @cyb0124 (this change is based on their idea)
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Comment threadlibrary/coretests/tests/option.rs
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Thanks! Looks good to me.
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@kpreid
In Option::get_or_insert_with(), forget the None instead of dropp…
c1b51dd
…ing it.
This allows eliminating the `T: [const] Destruct` bounds and avoids
generating an implicit `drop_in_place::<Option<T>>()` that will never do
anything.
Ideally, the compiler would prove that that drop is not necessary
itself, but it currently doesn't, even with `const_precise_live_drops`
enabled.
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The implementation looks good to me. r? libs-api for the unstable API change.
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Per advice:
@rustbot label -S-waiting-on-review +S-waiting-on-t-libs-api
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Can you check the final optimized runtime MIR before and after your change? I'm not sure we're optimizing the new code properly.
Also wondering about this pattern in general. Seems like sth const precise live drops could also handle, haven't looked at that in forever so I don't remember the details of it.
Anyway, if the final runtime MIR looks good, let's merge this
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Can you check the final optimized runtime MIR before and after your change? I'm not sure we're optimizing the new code properly.
I’m not familiar with how to do that, but I will look into it.
Seems like sth const precise live drops could also handle,
See prior discussion #148562 (comment) — in brief, having const_precise_live_drops would mean we are having the compiler doing static checking on how control flow affects values (whether the option is None), which is something that we generally only do for lint (e.g. if false {} is not counted as unreachable code).
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oli-obk and I have looked at the MIR through dropping both implementations into Compiler Explorer and it seems generally similar, but also not very optimized either before or after.
@rustbot label +const-hack
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📋 This PR cannot be approved because it currently has the following label: S-waiting-on-t-libs-api.
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Auto merge of#148562- kpreid:get-init-drop, r=oli-obk
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In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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Rollup merge ofrust-lang#148562- kpreid:get-init-drop, r=oli-obk
cef2175
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per rust-lang#148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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- #153621 (Remove `TyCtxt::node_span_lint` method)
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In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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A job failed! Check out the build log: (web)(plain enhanced)(plain)
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/dev/sda15 105M 6.2M 99M 6% /boot/efi
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================================================================================
Sufficient disk space available (95001912KB >= 52428800KB). Skipping cleanup.
##[group]Run src/ci/scripts/setup-environment.sh
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- #153325 (tests/ui/cfg: add annotations for reference rules)
- #153621 (Remove `TyCtxt::node_span_lint` method)
- #153627 (rustdoc-json: Improve docs for `ItemEnum::item_kind`)
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Rollup merge of #148562 - kpreid:get-init-drop, r=oli-obk
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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Auto merge of #153642 - matthiaskrgr:rollup-IHw8KqK, r=matthiaskrgr
88640a4
Rollup of 4 pull requests
Successful merges:
- rust-lang/rust#148562 (In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.)
- rust-lang/rust#153325 (tests/ui/cfg: add annotations for reference rules)
- rust-lang/rust#153621 (Remove `TyCtxt::node_span_lint` method)
- rust-lang/rust#153627 (rustdoc-json: Improve docs for `ItemEnum::item_kind`)
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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); }
})();
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try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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In Option::get_or_insert_with(), forget the None instead of dropping it. - #148562
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In Option::get_or_insert_with(), forget the None instead of dropping it.#148562
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Per #148486 (comment)
In Option::get_or_insert_with(), after replacing the None with Some, forget the None instead of dropping it.
This allows eliminating the T: [const] Destruct bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit drop_in_place::<Option<T>>() that will never do anything (and which might even persist after optimization).
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cc @cyb0124 (this change is based on their idea)
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Comment threadlibrary/coretests/tests/option.rs
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Thanks! Looks good to me.
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@kpreid
In Option::get_or_insert_with(), forget the None instead of dropp…
c1b51dd
…ing it.
This allows eliminating the `T: [const] Destruct` bounds and avoids
generating an implicit `drop_in_place::<Option<T>>()` that will never do
anything.
Ideally, the compiler would prove that that drop is not necessary
itself, but it currently doesn't, even with `const_precise_live_drops`
enabled.
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The implementation looks good to me. r? libs-api for the unstable API change.
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Per advice:
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Can you check the final optimized runtime MIR before and after your change? I'm not sure we're optimizing the new code properly.
Also wondering about this pattern in general. Seems like sth const precise live drops could also handle, haven't looked at that in forever so I don't remember the details of it.
Anyway, if the final runtime MIR looks good, let's merge this
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Can you check the final optimized runtime MIR before and after your change? I'm not sure we're optimizing the new code properly.
I’m not familiar with how to do that, but I will look into it.
Seems like sth const precise live drops could also handle,
See prior discussion #148562 (comment) — in brief, having const_precise_live_drops would mean we are having the compiler doing static checking on how control flow affects values (whether the option is None), which is something that we generally only do for lint (e.g. if false {} is not counted as unreachable code).
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oli-obk and I have looked at the MIR through dropping both implementations into Compiler Explorer and it seems generally similar, but also not very optimized either before or after.
@rustbot label +const-hack
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📋 This PR cannot be approved because it currently has the following label: S-waiting-on-t-libs-api.
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Auto merge of#148562- kpreid:get-init-drop, r=oli-obk
e7bce32
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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Rollup merge ofrust-lang#148562- kpreid:get-init-drop, r=oli-obk
cef2175
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per rust-lang#148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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Auto build was cancelled. Cancelled workflows:
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Auto merge of#153628- matthiaskrgr:rollup-V2cZQof, r=matthiaskrgr
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Successful merges:
- #148562 (In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.)
- #149931 (rustdoc: don't give depreciation notes special handling)
- #153608 (ast_passes: unsupported arch w/ scalable vectors)
- #153609 (Add missing `Diag::with_span_suggestion_with_style` method)
- #153610 (Only lint unused features if they are unstable)
- #153616 (Update `sysinfo` version to `0.38.4`)
- #153619 (Update books)
- #153624 (Ping fmease on parser modifications)
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50c1062
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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The dist-x86_64-linux job is stuck.
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Auto build was cancelled. Cancelled workflows:
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Auto merge of#153642- matthiaskrgr:rollup-IHw8KqK, r=matthiaskrgr
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Successful merges:
- #148562 (In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.)
- #153325 (tests/ui/cfg: add annotations for reference rules)
- #153621 (Remove `TyCtxt::node_span_lint` method)
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In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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💔 Test for 8744ff0 failed: CI. Failed job:
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Successful merges:
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- #153325 (tests/ui/cfg: add annotations for reference rules)
- #153621 (Remove `TyCtxt::node_span_lint` method)
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Auto merge of#153642- matthiaskrgr:rollup-IHw8KqK, r=matthiaskrgr
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Successful merges:
- #148562 (In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.)
- #153325 (tests/ui/cfg: add annotations for reference rules)
- #153621 (Remove `TyCtxt::node_span_lint` method)
- #153627 (rustdoc-json: Improve docs for `ItemEnum::item_kind`)
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Rollup merge of #148562 - kpreid:get-init-drop, r=oli-obk
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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Auto merge of #153642 - matthiaskrgr:rollup-IHw8KqK, r=matthiaskrgr
88640a4
Rollup of 4 pull requests
Successful merges:
- rust-lang/rust#148562 (In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.)
- rust-lang/rust#153325 (tests/ui/cfg: add annotations for reference rules)
- rust-lang/rust#153621 (Remove `TyCtxt::node_span_lint` method)
- rust-lang/rust#153627 (rustdoc-json: Improve docs for `ItemEnum::item_kind`)
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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" + '

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In Option::get_or_insert_with(), forget the None instead of dropping it. - #148562
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In Option::get_or_insert_with(), forget the None instead of dropping it.#148562
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Per #148486 (comment)
In Option::get_or_insert_with(), after replacing the None with Some, forget the None instead of dropping it.
This allows eliminating the T: [const] Destruct bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit drop_in_place::<Option<T>>() that will never do anything (and which might even persist after optimization).
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cc @cyb0124 (this change is based on their idea)
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Comment threadlibrary/coretests/tests/option.rs
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Comment threadlibrary/core/src/option.rs
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Thanks! Looks good to me.
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Comment threadlibrary/core/src/option.rs
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@kpreid
In Option::get_or_insert_with(), forget the None instead of dropp…
c1b51dd
…ing it.
This allows eliminating the `T: [const] Destruct` bounds and avoids
generating an implicit `drop_in_place::<Option<T>>()` that will never do
anything.
Ideally, the compiler would prove that that drop is not necessary
itself, but it currently doesn't, even with `const_precise_live_drops`
enabled.
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The implementation looks good to me. r? libs-api for the unstable API change.
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Per advice:
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Can you check the final optimized runtime MIR before and after your change? I'm not sure we're optimizing the new code properly.
Also wondering about this pattern in general. Seems like sth const precise live drops could also handle, haven't looked at that in forever so I don't remember the details of it.
Anyway, if the final runtime MIR looks good, let's merge this
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Can you check the final optimized runtime MIR before and after your change? I'm not sure we're optimizing the new code properly.
I’m not familiar with how to do that, but I will look into it.
Seems like sth const precise live drops could also handle,
See prior discussion #148562 (comment) — in brief, having const_precise_live_drops would mean we are having the compiler doing static checking on how control flow affects values (whether the option is None), which is something that we generally only do for lint (e.g. if false {} is not counted as unreachable code).
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oli-obk and I have looked at the MIR through dropping both implementations into Compiler Explorer and it seems generally similar, but also not very optimized either before or after.
@rustbot label +const-hack
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Auto merge of#148562- kpreid:get-init-drop, r=oli-obk
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In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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Rollup merge ofrust-lang#148562- kpreid:get-init-drop, r=oli-obk
cef2175
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per rust-lang#148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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- #148562 (In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.)
- #149931 (rustdoc: don't give depreciation notes special handling)
- #153608 (ast_passes: unsupported arch w/ scalable vectors)
- #153609 (Add missing `Diag::with_span_suggestion_with_style` method)
- #153610 (Only lint unused features if they are unstable)
- #153616 (Update `sysinfo` version to `0.38.4`)
- #153619 (Update books)
- #153624 (Ping fmease on parser modifications)
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In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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- #153325 (tests/ui/cfg: add annotations for reference rules)
- #153621 (Remove `TyCtxt::node_span_lint` method)
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/dev/sda15 105M 6.2M 99M 6% /boot/efi
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Auto merge of#153642- matthiaskrgr:rollup-IHw8KqK, r=matthiaskrgr
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- #153325 (tests/ui/cfg: add annotations for reference rules)
- #153621 (Remove `TyCtxt::node_span_lint` method)
- #153627 (rustdoc-json: Improve docs for `ItemEnum::item_kind`)
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Rollup merge of #148562 - kpreid:get-init-drop, r=oli-obk
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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Auto merge of #153642 - matthiaskrgr:rollup-IHw8KqK, r=matthiaskrgr
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Rollup of 4 pull requests
Successful merges:
- rust-lang/rust#148562 (In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.)
- rust-lang/rust#153325 (tests/ui/cfg: add annotations for reference rules)
- rust-lang/rust#153621 (Remove `TyCtxt::node_span_lint` method)
- rust-lang/rust#153627 (rustdoc-json: Improve docs for `ItemEnum::item_kind`)
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@kpreid@rustbot@ibraheemdev@oli-obk@ChrisDenton@matthiaskrgr@Zalathar@rust-log-analyzer@clarfonthey@hkBst@the8472

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} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
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In Option::get_or_insert_with(), forget the None instead of dropping it. - #148562
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In Option::get_or_insert_with(), forget the None instead of dropping it.#148562
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Per #148486 (comment)
In Option::get_or_insert_with(), after replacing the None with Some, forget the None instead of dropping it.
This allows eliminating the T: [const] Destruct bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit drop_in_place::<Option<T>>() that will never do anything (and which might even persist after optimization).
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r? @ibraheemdev
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cc @cyb0124 (this change is based on their idea)
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Comment threadlibrary/coretests/tests/option.rs
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Thanks! Looks good to me.
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Comment threadlibrary/core/src/option.rs
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@kpreid
In Option::get_or_insert_with(), forget the None instead of dropp…
c1b51dd
…ing it.
This allows eliminating the `T: [const] Destruct` bounds and avoids
generating an implicit `drop_in_place::<Option<T>>()` that will never do
anything.
Ideally, the compiler would prove that that drop is not necessary
itself, but it currently doesn't, even with `const_precise_live_drops`
enabled.
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The implementation looks good to me. r? libs-api for the unstable API change.
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Per advice:
@rustbot label -S-waiting-on-review +S-waiting-on-t-libs-api
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Error: Unknown labels: S-waiting-on-libs-api
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Can you check the final optimized runtime MIR before and after your change? I'm not sure we're optimizing the new code properly.
Also wondering about this pattern in general. Seems like sth const precise live drops could also handle, haven't looked at that in forever so I don't remember the details of it.
Anyway, if the final runtime MIR looks good, let's merge this
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Can you check the final optimized runtime MIR before and after your change? I'm not sure we're optimizing the new code properly.
I’m not familiar with how to do that, but I will look into it.
Seems like sth const precise live drops could also handle,
See prior discussion #148562 (comment) — in brief, having const_precise_live_drops would mean we are having the compiler doing static checking on how control flow affects values (whether the option is None), which is something that we generally only do for lint (e.g. if false {} is not counted as unreachable code).
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oli-obk and I have looked at the MIR through dropping both implementations into Compiler Explorer and it seems generally similar, but also not very optimized either before or after.
@rustbot label +const-hack
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📋 This PR cannot be approved because it currently has the following label: S-waiting-on-t-libs-api.
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Auto merge of#148562- kpreid:get-init-drop, r=oli-obk
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In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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Rollup merge ofrust-lang#148562- kpreid:get-init-drop, r=oli-obk
cef2175
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per rust-lang#148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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Auto merge of#153628- matthiaskrgr:rollup-V2cZQof, r=matthiaskrgr
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Successful merges:
- #148562 (In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.)
- #149931 (rustdoc: don't give depreciation notes special handling)
- #153608 (ast_passes: unsupported arch w/ scalable vectors)
- #153609 (Add missing `Diag::with_span_suggestion_with_style` method)
- #153610 (Only lint unused features if they are unstable)
- #153616 (Update `sysinfo` version to `0.38.4`)
- #153619 (Update books)
- #153624 (Ping fmease on parser modifications)
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In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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- #153325 (tests/ui/cfg: add annotations for reference rules)
- #153621 (Remove `TyCtxt::node_span_lint` method)
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A job failed! Check out the build log: (web)(plain enhanced)(plain)
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/dev/sda15 105M 6.2M 99M 6% /boot/efi
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================================================================================
Sufficient disk space available (95001912KB >= 52428800KB). Skipping cleanup.
##[group]Run src/ci/scripts/setup-environment.sh
src/ci/scripts/setup-environment.sh
shell: /usr/bin/bash --noprofile --norc -e -o pipefail {0}

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- #148562 (In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.)
- #153325 (tests/ui/cfg: add annotations for reference rules)
- #153621 (Remove `TyCtxt::node_span_lint` method)
- #153627 (rustdoc-json: Improve docs for `ItemEnum::item_kind`)
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Rollup merge of #148562 - kpreid:get-init-drop, r=oli-obk
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
@kpreid
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Auto merge of #153642 - matthiaskrgr:rollup-IHw8KqK, r=matthiaskrgr
88640a4
Rollup of 4 pull requests
Successful merges:
- rust-lang/rust#148562 (In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.)
- rust-lang/rust#153325 (tests/ui/cfg: add annotations for reference rules)
- rust-lang/rust#153621 (Remove `TyCtxt::node_span_lint` method)
- rust-lang/rust#153627 (rustdoc-json: Improve docs for `ItemEnum::item_kind`)
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, '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");
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In Option::get_or_insert_with(), forget the None instead of dropping it. - #148562
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In Option::get_or_insert_with(), forget the None instead of dropping it.#148562
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Per #148486 (comment)
In Option::get_or_insert_with(), after replacing the None with Some, forget the None instead of dropping it.
This allows eliminating the T: [const] Destruct bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit drop_in_place::<Option<T>>() that will never do anything (and which might even persist after optimization).
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cc @cyb0124 (this change is based on their idea)
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Comment threadlibrary/coretests/tests/option.rs
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Thanks! Looks good to me.
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@kpreid
In Option::get_or_insert_with(), forget the None instead of dropp…
c1b51dd
…ing it.
This allows eliminating the `T: [const] Destruct` bounds and avoids
generating an implicit `drop_in_place::<Option<T>>()` that will never do
anything.
Ideally, the compiler would prove that that drop is not necessary
itself, but it currently doesn't, even with `const_precise_live_drops`
enabled.
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The implementation looks good to me. r? libs-api for the unstable API change.
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Per advice:
@rustbot label -S-waiting-on-review +S-waiting-on-t-libs-api
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Error: Unknown labels: S-waiting-on-libs-api
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Can you check the final optimized runtime MIR before and after your change? I'm not sure we're optimizing the new code properly.
Also wondering about this pattern in general. Seems like sth const precise live drops could also handle, haven't looked at that in forever so I don't remember the details of it.
Anyway, if the final runtime MIR looks good, let's merge this
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Can you check the final optimized runtime MIR before and after your change? I'm not sure we're optimizing the new code properly.
I’m not familiar with how to do that, but I will look into it.
Seems like sth const precise live drops could also handle,
See prior discussion #148562 (comment) — in brief, having const_precise_live_drops would mean we are having the compiler doing static checking on how control flow affects values (whether the option is None), which is something that we generally only do for lint (e.g. if false {} is not counted as unreachable code).
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oli-obk and I have looked at the MIR through dropping both implementations into Compiler Explorer and it seems generally similar, but also not very optimized either before or after.
@rustbot label +const-hack
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Error: Unknown labels: const-hack
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@bors r+ rollup
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📋 This PR cannot be approved because it currently has the following label: S-waiting-on-t-libs-api.
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Auto merge of#148562- kpreid:get-init-drop, r=oli-obk
e7bce32
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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Rollup merge ofrust-lang#148562- kpreid:get-init-drop, r=oli-obk
cef2175
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per rust-lang#148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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Auto build was cancelled. Cancelled workflows:
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Auto merge of#153628- matthiaskrgr:rollup-V2cZQof, r=matthiaskrgr
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Rollup of 8 pull requests
Successful merges:
- #148562 (In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.)
- #149931 (rustdoc: don't give depreciation notes special handling)
- #153608 (ast_passes: unsupported arch w/ scalable vectors)
- #153609 (Add missing `Diag::with_span_suggestion_with_style` method)
- #153610 (Only lint unused features if they are unstable)
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- #153619 (Update books)
- #153624 (Ping fmease on parser modifications)
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In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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Auto build was cancelled. Cancelled workflows:
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Auto merge of#153642- matthiaskrgr:rollup-IHw8KqK, r=matthiaskrgr
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Rollup of 4 pull requests
Successful merges:
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- #153325 (tests/ui/cfg: add annotations for reference rules)
- #153621 (Remove `TyCtxt::node_span_lint` method)
- #153627 (rustdoc-json: Improve docs for `ItemEnum::item_kind`)
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Auto merge of#148562- kpreid:get-init-drop, r=oli-obk
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In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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💔 Test for 8744ff0 failed: CI. Failed job:
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- #153325 (tests/ui/cfg: add annotations for reference rules)
- #153621 (Remove `TyCtxt::node_span_lint` method)
- #153627 (rustdoc-json: Improve docs for `ItemEnum::item_kind`)
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- #153325 (tests/ui/cfg: add annotations for reference rules)
- #153621 (Remove `TyCtxt::node_span_lint` method)
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Unrolled build for#148562
33891b6
Rollup merge of #148562 - kpreid:get-init-drop, r=oli-obk
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
@kpreid
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flip1995 pushed a commit
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Auto merge of #153642 - matthiaskrgr:rollup-IHw8KqK, r=matthiaskrgr
88640a4
Rollup of 4 pull requests
Successful merges:
- rust-lang/rust#148562 (In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.)
- rust-lang/rust#153325 (tests/ui/cfg: add annotations for reference rules)
- rust-lang/rust#153621 (Remove `TyCtxt::node_span_lint` method)
- rust-lang/rust#153627 (rustdoc-json: Improve docs for `ItemEnum::item_kind`)
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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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In Option::get_or_insert_with(), forget the None instead of dropping it. - #148562
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In Option::get_or_insert_with(), forget the None instead of dropping it.#148562
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Per #148486 (comment)
In Option::get_or_insert_with(), after replacing the None with Some, forget the None instead of dropping it.
This allows eliminating the T: [const] Destruct bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit drop_in_place::<Option<T>>() that will never do anything (and which might even persist after optimization).
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cc @cyb0124 (this change is based on their idea)
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Thanks! Looks good to me.
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@kpreid
In Option::get_or_insert_with(), forget the None instead of dropp…
c1b51dd
…ing it.
This allows eliminating the `T: [const] Destruct` bounds and avoids
generating an implicit `drop_in_place::<Option<T>>()` that will never do
anything.
Ideally, the compiler would prove that that drop is not necessary
itself, but it currently doesn't, even with `const_precise_live_drops`
enabled.
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The implementation looks good to me. r? libs-api for the unstable API change.
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Per advice:
@rustbot label -S-waiting-on-review +S-waiting-on-t-libs-api
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Error: Unknown labels: S-waiting-on-libs-api
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Can you check the final optimized runtime MIR before and after your change? I'm not sure we're optimizing the new code properly.
Also wondering about this pattern in general. Seems like sth const precise live drops could also handle, haven't looked at that in forever so I don't remember the details of it.
Anyway, if the final runtime MIR looks good, let's merge this
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Can you check the final optimized runtime MIR before and after your change? I'm not sure we're optimizing the new code properly.
I’m not familiar with how to do that, but I will look into it.
Seems like sth const precise live drops could also handle,
See prior discussion #148562 (comment) — in brief, having const_precise_live_drops would mean we are having the compiler doing static checking on how control flow affects values (whether the option is None), which is something that we generally only do for lint (e.g. if false {} is not counted as unreachable code).
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oli-obk and I have looked at the MIR through dropping both implementations into Compiler Explorer and it seems generally similar, but also not very optimized either before or after.
@rustbot label +const-hack
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Error: Unknown labels: const-hack
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@bors r+ rollup
r? @oli-obk
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📋 This PR cannot be approved because it currently has the following label: S-waiting-on-t-libs-api.
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Auto merge of#148562- kpreid:get-init-drop, r=oli-obk
e7bce32
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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Rollup merge ofrust-lang#148562- kpreid:get-init-drop, r=oli-obk
cef2175
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per rust-lang#148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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Auto build was cancelled. Cancelled workflows:
The next pull request likely to be tested is #153628.
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Auto merge of#153628- matthiaskrgr:rollup-V2cZQof, r=matthiaskrgr
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Successful merges:
- #148562 (In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.)
- #149931 (rustdoc: don't give depreciation notes special handling)
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- #153619 (Update books)
- #153624 (Ping fmease on parser modifications)
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Auto merge of#148562- kpreid:get-init-drop, r=oli-obk
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In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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The dist-x86_64-linux job is stuck.
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Auto build was cancelled. Cancelled workflows:
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- #153621 (Remove `TyCtxt::node_span_lint` method)
- #153627 (rustdoc-json: Improve docs for `ItemEnum::item_kind`)
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Auto merge of#148562- kpreid:get-init-drop, r=oli-obk
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In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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💔 Test for 8744ff0 failed: CI. Failed job:
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@bors retry (network failure)
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Auto merge of#153642- matthiaskrgr:rollup-IHw8KqK, r=matthiaskrgr
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- #153325 (tests/ui/cfg: add annotations for reference rules)
- #153621 (Remove `TyCtxt::node_span_lint` method)
- #153627 (rustdoc-json: Improve docs for `ItemEnum::item_kind`)
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/dev/sda15 105M 6.2M 99M 6% /boot/efi
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================================================================================
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- #153325 (tests/ui/cfg: add annotations for reference rules)
- #153621 (Remove `TyCtxt::node_span_lint` method)
- #153627 (rustdoc-json: Improve docs for `ItemEnum::item_kind`)
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Unrolled build for#148562
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Rollup merge of #148562 - kpreid:get-init-drop, r=oli-obk
In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.
Per #148486 (comment)
In `Option::get_or_insert_with()`, after replacing the `None` with `Some`, forget the `None` instead of dropping it.
This allows eliminating the `T: [const] Destruct` bounds, making the functions more flexible in (unstable) const contexts, and avoids generating an implicit `drop_in_place::<Option<T>>()` that will never do anything (and which might even persist after optimization).
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Auto merge of #153642 - matthiaskrgr:rollup-IHw8KqK, r=matthiaskrgr
88640a4
Rollup of 4 pull requests
Successful merges:
- rust-lang/rust#148562 (In `Option::get_or_insert_with()`, forget the `None` instead of dropping it.)
- rust-lang/rust#153325 (tests/ui/cfg: add annotations for reference rules)
- rust-lang/rust#153621 (Remove `TyCtxt::node_span_lint` method)
- rust-lang/rust#153627 (rustdoc-json: Improve docs for `ItemEnum::item_kind`)
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