transmute size check: properly account for alignment #125740

RalfJung · 2024-05-29T20:08:54Z

Fixes another place where ZST alignment was ignored when checking whether something is a newtype. I wonder how many more of these there are...

Fixes #101084

rustbot · 2024-05-29T20:09:02Z

r? @pnkfelix

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compiler/rustc_middle/src/ty/layout.rs

RalfJung · 2024-06-11T11:54:33Z

r? compiler

Nadrieril · 2024-06-11T15:28:33Z

Looks reasonable but I'm not competent in this

r? compiler

oli-obk · 2024-06-24T13:12:47Z

r? @oli-obk

While the error message doesn't state the reason, that is preexisting with all the other cases and needs an approach for all sites

bors · 2024-06-24T13:12:50Z

📌 Commit 9f0c7f0 has been approved by oli-obk

It is now in the queue for this repository.

…li-obk transmute size check: properly account for alignment Fixes another place where ZST alignment was ignored when checking whether something is a newtype. I wonder how many more of these there are... Fixes rust-lang#101084

…iaskrgr Rollup of 10 pull requests Successful merges: - rust-lang#124460 (Show notice about "never used" of Debug for enum) - rust-lang#125740 (transmute size check: properly account for alignment) - rust-lang#126413 (compiletest: make the crash test error message abit more informative) - rust-lang#126618 (Mark assoc tys live only if the corresponding trait is live) - rust-lang#126673 (Ensure we don't accidentally succeed when we want to report an error) - rust-lang#126804 (On short error format, append primary span label to message) - rust-lang#126868 (not use offset when there is not ends with brace) - rust-lang#126893 (Eliminate the distinction between PREC_POSTFIX and PREC_PAREN precedence level) - rust-lang#126899 (Suggest inline const blocks for array initialization) - rust-lang#126909 (add `@kobzol` to bootstrap team for triagebot) r? `@ghost` `@rustbot` modify labels: rollup

bors · 2024-06-25T07:21:21Z

⌛ Testing commit 9f0c7f0 with merge bda221a...

bors · 2024-06-25T09:34:46Z

☀️ Test successful - checks-actions
Approved by: oli-obk
Pushing bda221a to master...

rust-timer · 2024-06-25T10:49:42Z

Finished benchmarking commit (bda221a): comparison URL.

Overall result: ❌✅ regressions and improvements - no action needed

@rustbot label: -perf-regression

Instruction count

This is a highly reliable metric that was used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	4.2%	[2.8%, 5.6%]	2
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-0.3%	[-0.3%, -0.3%]	1
All ❌✅ (primary)	-	-	0

Max RSS (memory usage)

Results (primary 3.4%, secondary 3.1%)

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	3.4%	[3.4%, 3.4%]	1
Regressions ❌ (secondary)	3.1%	[1.4%, 5.0%]	9
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	3.4%	[3.4%, 3.4%]	1

Cycles

Results (primary 2.9%, secondary -2.3%)

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	2.9%	[2.9%, 2.9%]	1
Regressions ❌ (secondary)	3.2%	[3.2%, 3.2%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-7.7%	[-7.7%, -7.7%]	1
All ❌✅ (primary)	2.9%	[2.9%, 2.9%]	1

Binary size

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

Bootstrap: 694.699s -> 693.956s (-0.11%)
Artifact size: 326.68 MiB -> 324.65 MiB (-0.62%)

This MR contains the following updates: | Package | Update | Change | |---|---|---| | [rust](https://github.com/rust-lang/rust) | minor | `1.80.1` -> `1.81.0` | MR created with the help of [el-capitano/tools/renovate-bot](https://gitlab.com/el-capitano/tools/renovate-bot). **Proposed changes to behavior should be submitted there as MRs.** --- ### Release Notes <details> <summary>rust-lang/rust (rust)</summary> ### [`v1.81.0`](https://github.com/rust-lang/rust/blob/HEAD/RELEASES.md#Version-1810-2024-09-05) [Compare Source](rust-lang/rust@1.80.1...1.81.0) \========================== <a id="1.81.0-Language"></a> ## Language - [Abort on uncaught panics in `extern "C"` functions.](rust-lang/rust#116088) - [Fix ambiguous cases of multiple `&` in elided self lifetimes.](rust-lang/rust#117967) - [Stabilize `#[expect]` for lints (RFC 2383),](rust-lang/rust#120924) like `#[allow]` with a warning if the lint is *not* fulfilled. - [Change method resolution to constrain hidden types instead of rejecting method candidates.](rust-lang/rust#123962) - [Bump `elided_lifetimes_in_associated_constant` to deny.](rust-lang/rust#124211) - [`offset_from`: always allow pointers to point to the same address.](rust-lang/rust#124921) - [Allow constraining opaque types during subtyping in the trait system.](rust-lang/rust#125447) - [Allow constraining opaque types during various unsizing casts.](rust-lang/rust#125610) - [Deny keyword lifetimes pre-expansion.](rust-lang/rust#126762) <a id="1.81.0-Compiler"></a> ## Compiler - [Make casts of pointers to trait objects stricter.](rust-lang/rust#120248) - [Check alias args for well-formedness even if they have escaping bound vars.](rust-lang/rust#123737) - [Deprecate no-op codegen option `-Cinline-threshold=...`.](rust-lang/rust#124712) - [Re-implement a type-size based limit.](rust-lang/rust#125507) - [Properly account for alignment in `transmute` size checks.](rust-lang/rust#125740) - [Remove the `box_pointers` lint.](rust-lang/rust#126018) - [Ensure the interpreter checks bool/char for validity when they are used in a cast.](rust-lang/rust#126265) - [Improve coverage instrumentation for functions containing nested items.](rust-lang/rust#127199) - Target changes: - [Add Tier 3 `no_std` Xtensa targets:](rust-lang/rust#125141) `xtensa-esp32-none-elf`, `xtensa-esp32s2-none-elf`, `xtensa-esp32s3-none-elf` - [Add Tier 3 `std` Xtensa targets:](rust-lang/rust#126380) `xtensa-esp32-espidf`, `xtensa-esp32s2-espidf`, `xtensa-esp32s3-espidf` - [Add Tier 3 i686 Redox OS target:](rust-lang/rust#126192) `i686-unknown-redox` - [Promote `arm64ec-pc-windows-msvc` to Tier 2.](rust-lang/rust#126039) - [Promote `loongarch64-unknown-linux-musl` to Tier 2 with host tools.](rust-lang/rust#126298) - [Enable full tools and profiler for LoongArch Linux targets.](rust-lang/rust#127078) - [Unconditionally warn on usage of `wasm32-wasi`.](rust-lang/rust#126662) (see compatibility note below) - Refer to Rust's \[platform support page]\[platform-support-doc] for more information on Rust's tiered platform support. <a id="1.81.0-Libraries"></a> ## Libraries - [Split core's `PanicInfo` and std's `PanicInfo`.](rust-lang/rust#115974) (see compatibility note below) - [Generalize `{Rc,Arc}::make_mut()` to unsized types.](rust-lang/rust#116113) - [Replace sort implementations with stable `driftsort` and unstable `ipnsort`.](rust-lang/rust#124032) All `slice::sort*` and `slice::select_nth*` methods are expected to see significant performance improvements. See the [research project](https://github.com/Voultapher/sort-research-rs) for more details. - [Document behavior of `create_dir_all` with respect to empty paths.](rust-lang/rust#125112) - [Fix interleaved output in the default panic hook when multiple threads panic simultaneously.](rust-lang/rust#127397) <a id="1.81.0-Stabilized-APIs"></a> ## Stabilized APIs - [`core::error`](https://doc.rust-lang.org/stable/core/error/index.html) - [`hint::assert_unchecked`](https://doc.rust-lang.org/stable/core/hint/fn.assert_unchecked.html) - [`fs::exists`](https://doc.rust-lang.org/stable/std/fs/fn.exists.html) - [`AtomicBool::fetch_not`](https://doc.rust-lang.org/stable/core/sync/atomic/struct.AtomicBool.html#method.fetch_not) - [`Duration::abs_diff`](https://doc.rust-lang.org/stable/core/time/struct.Duration.html#method.abs_diff) - [`IoSlice::advance`](https://doc.rust-lang.org/stable/std/io/struct.IoSlice.html#method.advance) - [`IoSlice::advance_slices`](https://doc.rust-lang.org/stable/std/io/struct.IoSlice.html#method.advance_slices) - [`IoSliceMut::advance`](https://doc.rust-lang.org/stable/std/io/struct.IoSliceMut.html#method.advance) - [`IoSliceMut::advance_slices`](https://doc.rust-lang.org/stable/std/io/struct.IoSliceMut.html#method.advance_slices) - [`PanicHookInfo`](https://doc.rust-lang.org/stable/std/panic/struct.PanicHookInfo.html) - [`PanicInfo::message`](https://doc.rust-lang.org/stable/core/panic/struct.PanicInfo.html#method.message) - [`PanicMessage`](https://doc.rust-lang.org/stable/core/panic/struct.PanicMessage.html) These APIs are now stable in const contexts: - [`char::from_u32_unchecked`](https://doc.rust-lang.org/stable/core/char/fn.from_u32\_unchecked.html) (function) - [`char::from_u32_unchecked`](https://doc.rust-lang.org/stable/core/primitive.char.html#method.from_u32\_unchecked) (method) - [`CStr::count_bytes`](https://doc.rust-lang.org/stable/core/ffi/c_str/struct.CStr.html#method.count_bytes) - [`CStr::from_ptr`](https://doc.rust-lang.org/stable/core/ffi/c_str/struct.CStr.html#method.from_ptr) <a id="1.81.0-Cargo"></a> ## Cargo - [Generated `.cargo_vcs_info.json` is always included, even when `--allow-dirty` is passed.](rust-lang/cargo#13960) - [Disallow `package.license-file` and `package.readme` pointing to non-existent files during packaging.](rust-lang/cargo#13921) - [Disallow passing `--release`/`--debug` flag along with the `--profile` flag.](rust-lang/cargo#13971) - [Remove `lib.plugin` key support in `Cargo.toml`. Rust plugin support has been deprecated for four years and was removed in 1.75.0.](rust-lang/cargo#13902) <a id="1.81.0-Compatibility-Notes"></a> ## Compatibility Notes - Usage of the `wasm32-wasi` target will now issue a compiler warning and request users switch to the `wasm32-wasip1` target instead. Both targets are the same, `wasm32-wasi` is only being renamed, and this [change to the WASI target](https://blog.rust-lang.org/2024/04/09/updates-to-rusts-wasi-targets.html) is being done to enable removing `wasm32-wasi` in January 2025. - We have renamed `std::panic::PanicInfo` to `std::panic::PanicHookInfo`. The old name will continue to work as an alias, but will result in a deprecation warning starting in Rust 1.82.0. `core::panic::PanicInfo` will remain unchanged, however, as this is now a *different type*. The reason is that these types have different roles: `std::panic::PanicHookInfo` is the argument to the [panic hook](https://doc.rust-lang.org/stable/std/panic/fn.set_hook.html) in std context (where panics can have an arbitrary payload), while `core::panic::PanicInfo` is the argument to the [`#[panic_handler]`](https://doc.rust-lang.org/nomicon/panic-handler.html) in no_std context (where panics always carry a formatted *message*). Separating these types allows us to add more useful methods to these types, such as `std::panic::PanicHookInfo::payload_as_str()` and `core::panic::PanicInfo::message()`. - The new sort implementations may panic if a type's implementation of [`Ord`](https://doc.rust-lang.org/std/cmp/trait.Ord.html) (or the given comparison function) does not implement a [total order](https://en.wikipedia.org/wiki/Total_order) as the trait requires. `Ord`'s supertraits (`PartialOrd`, `Eq`, and `PartialEq`) must also be consistent. The previous implementations would not "notice" any problem, but the new implementations have a good chance of detecting inconsistencies, throwing a panic rather than returning knowingly unsorted data. - [In very rare cases, a change in the internal evaluation order of the trait solver may result in new fatal overflow errors.](rust-lang/rust#126128) <a id="1.81.0-Internal-Changes"></a> ## Internal Changes These changes do not affect any public interfaces of Rust, but they represent significant improvements to the performance or internals of rustc and related tools. - [Add a Rust-for Linux `auto` CI job to check kernel builds.](rust-lang/rust#125209) </details> --- ### Configuration 📅 **Schedule**: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined). 🚦 **Automerge**: Disabled by config. Please merge this manually once you are satisfied. ♻ **Rebasing**: Whenever MR becomes conflicted, or you tick the rebase/retry checkbox. 🔕 **Ignore**: Close this MR and you won't be reminded about this update again. --- - [ ] If you want to rebase/retry this MR, check this box --- This MR has been generated by [Renovate Bot](https://github.com/renovatebot/renovate).

rustbot assigned pnkfelix May 29, 2024

rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels May 29, 2024

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RalfJung force-pushed the transmute-size-check branch from bc5f9ad to 656341a Compare May 29, 2024 20:34

zachs18 reviewed May 29, 2024

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compiler/rustc_middle/src/ty/layout.rs Outdated Show resolved Hide resolved

RalfJung force-pushed the transmute-size-check branch from 656341a to 984eafc Compare May 30, 2024 05:39

transmute size check: properly account for alignment

9f0c7f0

RalfJung force-pushed the transmute-size-check branch from 984eafc to 9f0c7f0 Compare May 30, 2024 08:06

RalfJung added the relnotes Marks issues that should be documented in the release notes of the next release. label Jun 11, 2024

rustbot assigned Nadrieril and unassigned pnkfelix Jun 11, 2024

rustbot assigned TaKO8Ki and unassigned Nadrieril Jun 11, 2024

rustbot assigned oli-obk and unassigned TaKO8Ki Jun 24, 2024

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 Jun 24, 2024

matthiaskrgr mentioned this pull request Jun 24, 2024

Rollup of 10 pull requests #126910

Closed

matthiaskrgr mentioned this pull request Jun 24, 2024

Rollup of 10 pull requests #126912

Closed

bors added the merged-by-bors This PR was explicitly merged by bors. label Jun 25, 2024

bors merged commit bda221a into rust-lang:master Jun 25, 2024
7 checks passed

rustbot added this to the 1.81.0 milestone Jun 25, 2024

lqd mentioned this pull request Jun 26, 2024

Rollup of 8 pull requests #126965

Merged

RalfJung deleted the transmute-size-check branch June 29, 2024 10:01

Johnson1s mentioned this pull request Sep 6, 2024

Fixes another place where ZST alignment was ignored when checking whether something is a newtype. I wonder how many more of these there are... neodyme-labs/solana-security-txt#62

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transmute size check: properly account for alignment #125740

transmute size check: properly account for alignment #125740

RalfJung commented May 29, 2024

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rust-timer commented Jun 25, 2024

transmute size check: properly account for alignment #125740

transmute size check: properly account for alignment #125740

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RalfJung commented May 29, 2024

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rust-timer commented Jun 25, 2024

Overall result: ❌✅ regressions and improvements - no action needed

Instruction count

Max RSS (memory usage)

Cycles

Binary size