Guarantee 8 bytes of alignment in Thread::into_raw #143859
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r? libs-api, this adds an alignment guarantee to the unstable |
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ping @rust-lang/libs-api, as this provides a new guarantee, arguably needing FCP (and at a minimum team involvement) |
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@rfcbot fcp merge |
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Team member @dtolnay 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. |
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🔔 This is now entering its final comment period, as per the review above. 🔔 |
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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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@bors r+ rollup |
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Guarantee 8 bytes of alignment in Thread::into_raw When using `AtomicPtr` for synchronization it's incredibly useful when you've got a couple bits you can stuff metadata in. By guaranteeing that `Thread`'s `Inner` struct is aligned to 8 bytes everyone can use the bottom 3 bits to signal other things, such as a critical section, etc. This guarantee is thus very useful and costs us nothing.
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Guarantee 8 bytes of alignment in Thread::into_raw When using `AtomicPtr` for synchronization it's incredibly useful when you've got a couple bits you can stuff metadata in. By guaranteeing that `Thread`'s `Inner` struct is aligned to 8 bytes everyone can use the bottom 3 bits to signal other things, such as a critical section, etc. This guarantee is thus very useful and costs us nothing.
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Rollup of 9 pull requests Successful merges: - #140871 (Don't lint against named labels in `naked_asm!`) - #141663 (rustdoc: add ways of collapsing all impl blocks) - #143272 (Upgrade the `fortanix-sgx-abi` dependency) - #143585 (`loop_match`: suggest extracting to a `const` item) - #143698 (Fix unused_parens false positive) - #143859 (Guarantee 8 bytes of alignment in Thread::into_raw) - #144042 (Verify llvm-needs-components are not empty and match the --target value) - #144160 (tests: debuginfo: Work around or disable broken tests on powerpc) - #144431 (Disable has_reliable_f128_math on musl targets) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup of 9 pull requests Successful merges: - #140871 (Don't lint against named labels in `naked_asm!`) - #141663 (rustdoc: add ways of collapsing all impl blocks) - #143272 (Upgrade the `fortanix-sgx-abi` dependency) - #143585 (`loop_match`: suggest extracting to a `const` item) - #143698 (Fix unused_parens false positive) - #143859 (Guarantee 8 bytes of alignment in Thread::into_raw) - #144160 (tests: debuginfo: Work around or disable broken tests on powerpc) - #144412 (Small cleanup: Use LocalKey<Cell> methods more) - #144431 (Disable has_reliable_f128_math on musl targets) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of #143859 - orlp:thread-into-raw-align, r=jhpratt Guarantee 8 bytes of alignment in Thread::into_raw When using `AtomicPtr` for synchronization it's incredibly useful when you've got a couple bits you can stuff metadata in. By guaranteeing that `Thread`'s `Inner` struct is aligned to 8 bytes everyone can use the bottom 3 bits to signal other things, such as a critical section, etc. This guarantee is thus very useful and costs us nothing.
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When using
AtomicPtrfor synchronization it's incredibly useful when you've got a couple bits you can stuff metadata in. By guaranteeing thatThread'sInnerstruct is aligned to 8 bytes everyone can use the bottom 3 bits to signal other things, such as a critical section, etc.This guarantee is thus very useful and costs us nothing.