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merged 1 commit into from
Oct 16, 2021
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Stabilize unreachable_unchecked as const fn #89509

merged 1 commit into from
Oct 16, 2021

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jhpratt
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@jhpratt jhpratt commented Oct 4, 2021

Closes #53188

This PR stabilizes core::hint::unreachable_unchecked as const fn. MIRI is able to detect when this method is called. Stabilization was delayed until const_panic was stabilized so as to avoid users calling this method in its place (thus resulting in runtime UB). With #89508, that is no longer an issue.

@rustbot label +A-const-eval +A-const-fn +T-lang +S-blocked

(not sure why it's T-lang, but that's what the tracking issue is)

@rustbot rustbot added A-const-eval Area: Constant evaluation, covers all const contexts (static, const fn, ...) A-const-fn S-blocked Status: Blocked on something else such as an RFC or other implementation work. T-lang Relevant to the language team, which will review and decide on the PR/issue. labels Oct 4, 2021
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r? @Mark-Simulacrum

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@rust-highfive rust-highfive added the S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. label Oct 4, 2021
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@bors r+

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bors commented Oct 4, 2021

📌 Commit 11140ff has been approved by joshtriplett

@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-review Status: Awaiting review from the assignee but also interested parties. S-blocked Status: Blocked on something else such as an RFC or other implementation work. labels Oct 4, 2021
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@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 Oct 4, 2021
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@rfcbot merge

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rfcbot commented Oct 4, 2021 •
edited by scottmcm
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Team member @joshtriplett has proposed to merge this. The next step is review by the rest of the tagged team members:

No concerns currently listed.

Once a majority of reviewers approve (and at most 2 approvals are outstanding), this will enter its final comment period. If you spot a major issue that hasn't been raised at any point in this process, please speak up!

See this document for info about what commands tagged team members can give me.

@rfcbot rfcbot added proposed-final-comment-period Proposed to merge/close by relevant subteam, see T-<team> label. Will enter FCP once signed off. disposition-merge This issue / PR is in PFCP or FCP with a disposition to merge it. labels Oct 4, 2021
@joshtriplett joshtriplett added the relnotes Marks issues that should be documented in the release notes of the next release. label Oct 4, 2021
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I'd like to see @RalfJung or @oli-obk weigh in, or perhaps a brief stabilization report. I'm not really particularly familiar with this intrinsic, I have to admit.

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RalfJung commented Oct 4, 2021

Yeah, this intrinsic is basically the simplest kind of UB we have, so with const_panic stable I see no reason not to stabilize this as well.

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@rfcbot fcp reviewed :)

@rfcbot rfcbot added final-comment-period In the final comment period and will be merged soon unless new substantive objections are raised. and removed proposed-final-comment-period Proposed to merge/close by relevant subteam, see T-<team> label. Will enter FCP once signed off. labels Oct 4, 2021
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rfcbot commented Oct 4, 2021

🔔 This is now entering its final comment period, as per the review above. 🔔

@rfcbot rfcbot added finished-final-comment-period The final comment period is finished for this PR / Issue. to-announce Announce this issue on triage meeting and removed final-comment-period In the final comment period and will be merged soon unless new substantive objections are raised. labels Oct 14, 2021
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rfcbot commented Oct 14, 2021

The final comment period, with a disposition to merge, as per the review above, is now complete.

As the automated representative of the governance process, I would like to thank the author for their work and everyone else who contributed.

This will be merged soon.

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oli-obk commented Oct 14, 2021

@bors r+

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bors commented Oct 14, 2021

📌 Commit 11140ff has been approved by oli-obk

@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 Oct 14, 2021
JohnTitor added a commit to JohnTitor/rust that referenced this pull request Oct 15, 2021
@JohnTitor
Rollup merge of rust-lang#89509 - jhpratt:stabilize-const_unreachable…
d9a9d6e 
…_unchecked, r=oli-obk

Stabilize `unreachable_unchecked` as `const fn`

Closes rust-lang#53188

This PR stabilizes `core::hint::unreachable_unchecked` as `const fn`. MIRI is able to detect when this method is called. Stabilization was delayed until `const_panic` was stabilized so as to avoid users calling this method in its place (thus resulting in runtime UB). With rust-lang#89508, that is no longer an issue.

`@rustbot` label +A-const-eval +A-const-fn +T-lang +S-blocked

(not sure why it's T-lang, but that's what the tracking issue is)
@JohnTitor JohnTitor mentioned this pull request Oct 15, 2021
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@bors rollup

matthiaskrgr added a commit to matthiaskrgr/rust that referenced this pull request Oct 15, 2021
@matthiaskrgr
Rollup merge of rust-lang#89509 - jhpratt:stabilize-const_unreachable…
16bdcdb 
…_unchecked, r=oli-obk

Stabilize `unreachable_unchecked` as `const fn`

Closes rust-lang#53188

This PR stabilizes `core::hint::unreachable_unchecked` as `const fn`. MIRI is able to detect when this method is called. Stabilization was delayed until `const_panic` was stabilized so as to avoid users calling this method in its place (thus resulting in runtime UB). With rust-lang#89508, that is no longer an issue.

`@rustbot` label +A-const-eval +A-const-fn +T-lang +S-blocked

(not sure why it's T-lang, but that's what the tracking issue is)
@matthiaskrgr matthiaskrgr mentioned this pull request Oct 15, 2021
Closed
matthiaskrgr added a commit to matthiaskrgr/rust that referenced this pull request Oct 15, 2021
@matthiaskrgr
Rollup merge of rust-lang#89509 - jhpratt:stabilize-const_unreachable…
38d2699 
…_unchecked, r=oli-obk

Stabilize `unreachable_unchecked` as `const fn`

Closes rust-lang#53188

This PR stabilizes `core::hint::unreachable_unchecked` as `const fn`. MIRI is able to detect when this method is called. Stabilization was delayed until `const_panic` was stabilized so as to avoid users calling this method in its place (thus resulting in runtime UB). With rust-lang#89508, that is no longer an issue.

``@rustbot`` label +A-const-eval +A-const-fn +T-lang +S-blocked

(not sure why it's T-lang, but that's what the tracking issue is)
@matthiaskrgr matthiaskrgr mentioned this pull request Oct 15, 2021
Closed
jackh726 added a commit to jackh726/rust that referenced this pull request Oct 16, 2021
@jackh726
Rollup merge of rust-lang#89509 - jhpratt:stabilize-const_unreachable…
3669d56 
…_unchecked, r=oli-obk

Stabilize `unreachable_unchecked` as `const fn`

Closes rust-lang#53188

This PR stabilizes `core::hint::unreachable_unchecked` as `const fn`. MIRI is able to detect when this method is called. Stabilization was delayed until `const_panic` was stabilized so as to avoid users calling this method in its place (thus resulting in runtime UB). With rust-lang#89508, that is no longer an issue.

```@rustbot``` label +A-const-eval +A-const-fn +T-lang +S-blocked

(not sure why it's T-lang, but that's what the tracking issue is)
@jackh726 jackh726 mentioned this pull request Oct 16, 2021
Closed
@matthiaskrgr matthiaskrgr mentioned this pull request Oct 16, 2021
Merged
bors added a commit to rust-lang-ci/rust that referenced this pull request Oct 16, 2021
@bors
Auto merge of rust-lang#89939 - matthiaskrgr:rollup-q3lrdck, r=matthi…
7fbd4ce 
…askrgr

Rollup of 10 pull requests

Successful merges:

 - rust-lang#89509 (Stabilize `unreachable_unchecked` as `const fn`)
 - rust-lang#89898 (Remove alloc::prelude)
 - rust-lang#89902 (Restrict the aarch64 outline atomics test to Linux)
 - rust-lang#89906 (Moved format-version constant to rustdoc-json-types)
 - rust-lang#89912 (emitter: current substitution can be multi-line)
 - rust-lang#89914 (Emit impl difference error for GenericBoundFailure too)
 - rust-lang#89915 (Some outlives cleanup)
 - rust-lang#89918 (Add some GATs related regression tests)
 - rust-lang#89921 ([fuchsia] Update process info struct)
 - rust-lang#89925 (updating docs to mention usage of AtomicBool)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
@bors bors merged commit 9ae0804 into rust-lang:master Oct 16, 2021
@rustbot rustbot added this to the 1.57.0 milestone Oct 16, 2021
@jhpratt jhpratt deleted the stabilize-const_unreachable_unchecked branch October 16, 2021 09:53
@ojeda ojeda mentioned this pull request Oct 16, 2021
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@jplatte jplatte mentioned this pull request Oct 21, 2021
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@apiraino apiraino removed the to-announce Announce this issue on triage meeting label Oct 21, 2021
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A-const-eval Area: Constant evaluation, covers all const contexts (static, const fn, ...) disposition-merge This issue / PR is in PFCP or FCP with a disposition to merge it. finished-final-comment-period The final comment period is finished for this PR / Issue. relnotes Marks issues that should be documented in the release notes of the next release. S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. T-lang Relevant to the language team, which will review and decide on the PR/issue.
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Successfully merging this pull request may close these issues.

Tracking Issue for const unreachable_unchecked