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explain mem::forget(env_lock) in fork/exec #105598

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Merged
merged 1 commit into from
Dec 14, 2022
Merged

explain mem::forget(env_lock) in fork/exec #105598

merged 1 commit into from
Dec 14, 2022

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RalfJung
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I stumbled upon this while doing triage for #64718.

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rustbot commented Dec 12, 2022

r? @m-ou-se

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@rustbot rustbot 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 Dec 12, 2022
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rustbot commented Dec 12, 2022

Hey! It looks like you've submitted a new PR for the library teams!

If this PR contains changes to any rust-lang/rust public library APIs then please comment with @rustbot label +T-libs-api -T-libs to tag it appropriately. If this PR contains changes to any unstable APIs please edit the PR description to add a link to the relevant API Change Proposal or create one if you haven't already. If you're unsure where your change falls no worries, just leave it as is and the reviewer will take a look and make a decision to forward on if necessary.

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the8472 commented Dec 12, 2022

That's already covered by the comment ~5 lines up

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Kinda... that comment makes it sounds like this is just an optimization. It does not at all make it clear that the forget is crucial for soundness.

@the8472 the8472 assigned the8472 and unassigned m-ou-se Dec 13, 2022
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the8472 commented Dec 13, 2022

I mean it did say unlocking in the child would be invalid. But ok, the new comment is clearer.

@bors r+ rollup

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bors commented Dec 13, 2022

📌 Commit 3465d5f has been approved by the8472

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-review Status: Awaiting review from the assignee but also interested parties. labels Dec 13, 2022
@matthiaskrgr matthiaskrgr mentioned this pull request Dec 14, 2022
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bors added a commit to rust-lang-ci/rust that referenced this pull request Dec 14, 2022
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Auto merge of rust-lang#105703 - matthiaskrgr:rollup-tfpeam2, r=matth…
b70baa4 
…iaskrgr

Rollup of 7 pull requests

Successful merges:

 - rust-lang#105399 (Use more LFS functions.)
 - rust-lang#105578 (Fix transmutes between pointers in different address spaces (e.g. fn ptrs on AVR))
 - rust-lang#105598 (explain mem::forget(env_lock) in fork/exec)
 - rust-lang#105624 (Fix unsoundness in bootstrap cache code)
 - rust-lang#105630 (Add a test for rust-lang#92481)
 - rust-lang#105684 (Improve rustdoc markdown variable naming)
 - rust-lang#105697 (Remove fee1-dead from reviewers)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
@bors bors merged commit 6d3a93c into rust-lang:master Dec 14, 2022
@rustbot rustbot added this to the 1.68.0 milestone Dec 14, 2022
@RalfJung RalfJung deleted the more-comments branch December 21, 2022 10:04
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