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Merged
merged 1 commit into from
Dec 4, 2023
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codegen, miri: fix computing the offset of an unsized field in a packed struct #118540

merged 1 commit into from
Dec 4, 2023

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RalfJung
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@RalfJung RalfJung commented Dec 2, 2023

#[repr(packed)] strikes again.

Fixes #118537
Fixes rust-lang/miri#3200

@bjorn3 I assume cranelift needs the same fix.

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r? @TaKO8Ki

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@rustbot 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 Dec 2, 2023
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rustbot commented Dec 2, 2023

Some changes occurred to the CTFE / Miri engine

cc @rust-lang/miri

The Miri subtree was changed

cc @rust-lang/miri

RalfJung
RalfJung commented Dec 2, 2023
View reviewed changes
compiler/rustc_codegen_ssa/src/mir/place.rs
@@ -154,14 +153,6 @@ impl<'a, 'tcx, V: CodegenObject> PlaceRef<'tcx, V> {
}
_ if field.is_sized() => return simple(),
ty::Slice(..) | ty::Str | ty::Foreign(..) => return simple(),
ty::Adt(def, _) => {
if def.repr().packed() {
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We could have tried to preserve this fast-path for some packed structs, but I don't think that's worth it.

@RalfJung RalfJung force-pushed the unsized-packed-offset branch from 75729bd to ef15a81 Compare December 3, 2023 07:26
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apiraino commented Dec 4, 2023

r? compiler

@rustbot rustbot assigned b-naber and unassigned TaKO8Ki Dec 4, 2023
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TaKO8Ki commented Dec 4, 2023

@bors r+ rollup

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bors commented Dec 4, 2023

📌 Commit ef15a81 has been approved by TaKO8Ki

It is now in the queue for this repository.

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bors commented Dec 4, 2023

🌲 The tree is currently closed for pull requests below priority 10. This pull request will be tested once the tree is reopened.

@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 4, 2023
@TaKO8Ki TaKO8Ki mentioned this pull request Dec 4, 2023
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bors added a commit to rust-lang-ci/rust that referenced this pull request Dec 4, 2023
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Auto merge of rust-lang#118602 - TaKO8Ki:rollup-njcouns, r=TaKO8Ki
e281163 
Rollup of 5 pull requests

Successful merges:

 - rust-lang#118495 (Restrict what symbols can be used in `#[diagnostic::on_unimplemented]` format strings)
 - rust-lang#118540 (codegen, miri: fix computing the offset of an unsized field in a packed struct)
 - rust-lang#118551 (more targeted errors when extern types end up in places they should not)
 - rust-lang#118573 (rustc: Harmonize `DefKind` and `DefPathData`)
 - rust-lang#118586 (Improve example in `slice::windows()` doc)

r? `@ghost`
`@rustbot` modify labels: rollup
@bors bors merged commit 87625db into rust-lang:master Dec 4, 2023
@rustbot rustbot added this to the 1.76.0 milestone Dec 4, 2023
rust-timer added a commit to rust-lang-ci/rust that referenced this pull request Dec 4, 2023
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Unrolled build for rust-lang#118540
325ce11 
Rollup merge of rust-lang#118540 - RalfJung:unsized-packed-offset, r=TaKO8Ki

codegen, miri: fix computing the offset of an unsized field in a packed struct

`#[repr(packed)]`  strikes again.

Fixes rust-lang#118537
Fixes rust-lang/miri#3200

`@bjorn3` I assume cranelift needs the same fix.
@RalfJung RalfJung deleted the unsized-packed-offset branch December 4, 2023 18:09
This was referenced Dec 13, 2023
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@WaffleLapkin should this one also be marked as "relnotes"?

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@RalfJung I think so

@WaffleLapkin WaffleLapkin added the relnotes Marks issues that should be documented in the release notes of the next release. label Dec 14, 2023
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For the relnotes this should probably be grouped with #118538. One fixes the logic for computing the offset of an unsized field in a packed struct, the other fixes the logic for computing the size and alignment of an unsized packed struct.

bjorn3 added a commit to rust-lang/rustc_codegen_cranelift that referenced this pull request Dec 18, 2023
@bjorn3
fix computing the offset of an unsized field in a packed struct
973dd56 
cc rust-lang/rust#118540
Fixes #1435
wip-sync pushed a commit to NetBSD/pkgsrc-wip that referenced this pull request Feb 18, 2024
@he32
Add a package for rust version 1.76.0.
0e9a2a1 
Pkgsrc changes:
 * Adapt checksums and patches.

Upstream chnages:

Version 1.76.0 (2024-02-08)
==========================

Language
--------
- [Document Rust ABI compatibility between various types]
  (rust-lang/rust#115476)
- [Also: guarantee that char and u32 are ABI-compatible]
  (rust-lang/rust#118032)
- [Warn against ambiguous wide pointer comparisons]
  (rust-lang/rust#117758)

Compiler
--------
- [Lint pinned `#[must_use]` pointers (in particular, `Box<T>`
  where `T` is `#[must_use]`) in `unused_must_use`.]
  (rust-lang/rust#118054)
- [Soundness fix: fix computing the offset of an unsized field in
  a packed struct]
  (rust-lang/rust#118540)
- [Soundness fix: fix dynamic size/align computation logic for
  packed types with dyn Trait tail]
  (rust-lang/rust#118538)
- [Add `$message_type` field to distinguish json diagnostic outputs]
  (rust-lang/rust#115691)
- [Enable Rust to use the EHCont security feature of Windows]
  (rust-lang/rust#118013)
- [Add tier 3 {x86_64,i686}-win7-windows-msvc targets]
  (rust-lang/rust#118150)
- [Add tier 3 aarch64-apple-watchos target]
  (rust-lang/rust#119074)
- [Add tier 3 arm64e-apple-ios & arm64e-apple-darwin targets]
  (rust-lang/rust#115526)

Refer to Rust's [platform support page][platform-support-doc]
for more information on Rust's tiered platform support.

Libraries
---------
- [Add a column number to `dbg!()`]
  (rust-lang/rust#114962)
- [Add `std::hash::{DefaultHasher, RandomState}` exports]
  (rust-lang/rust#115694)
- [Fix rounding issue with exponents in fmt]
  (rust-lang/rust#116301)
- [Add T: ?Sized to `RwLockReadGuard` and `RwLockWriteGuard`'s Debug impls.]
  (rust-lang/rust#117138)
- [Windows: Allow `File::create` to work on hidden files]
  (rust-lang/rust#116438)

Stabilized APIs
---------------
- [`Arc::unwrap_or_clone`]
  (https://doc.rust-lang.org/stable/std/sync/struct.Arc.html#method.unwrap_or_clone)
- [`Rc::unwrap_or_clone`]
  (https://doc.rust-lang.org/stable/std/rc/struct.Rc.html#method.unwrap_or_clone)
- [`Result::inspect`]
  (https://doc.rust-lang.org/stable/std/result/enum.Result.html#method.inspect)
- [`Result::inspect_err`]
  (https://doc.rust-lang.org/stable/std/result/enum.Result.html#method.inspect_err)
- [`Option::inspect`]
  (https://doc.rust-lang.org/stable/std/option/enum.Option.html#method.inspect)
- [`type_name_of_val`]
  (https://doc.rust-lang.org/stable/std/any/fn.type_name_of_val.html)
- [`std::hash::{DefaultHasher, RandomState}`]
  (https://doc.rust-lang.org/stable/std/hash/index.html#structs)
  These were previously available only through `std::collections::hash_map`.
- [`ptr::{from_ref, from_mut}`]
  (https://doc.rust-lang.org/stable/std/ptr/fn.from_ref.html)
- [`ptr::addr_eq`](https://doc.rust-lang.org/stable/std/ptr/fn.addr_eq.html)

Cargo
-----

See [Cargo release notes]
(https://github.com/rust-lang/cargo/blob/master/CHANGELOG.md#cargo-176-2024-02-08).

Rustdoc
-------
- [Don't merge cfg and doc(cfg) attributes for re-exports]
  (rust-lang/rust#113091)
- [rustdoc: allow resizing the sidebar / hiding the top bar]
  (rust-lang/rust#115660)
- [rustdoc-search: add support for traits and associated types]
  (rust-lang/rust#116085)
- [rustdoc: Add highlighting for comments in items declaration]
  (rust-lang/rust#117869)

Compatibility Notes
-------------------
- [Add allow-by-default lint for unit bindings]
  (rust-lang/rust#112380)
  This is expected to be upgraded to a warning by default in a future Rust
  release. Some macros emit bindings with type `()` with user-provided spans,
  which means that this lint will warn for user code.
- [Remove x86_64-sun-solaris target.]
  (rust-lang/rust#118091)
- [Remove asmjs-unknown-emscripten target]
  (rust-lang/rust#117338)
- [Report errors in jobserver inherited through environment variables]
  (rust-lang/rust#113730)
  This [may warn](rust-lang/rust#120515)
  on benign problems too.
- [Update the minimum external LLVM to 16.]
  (rust-lang/rust#117947)
- [Improve `print_tts`](rust-lang/rust#114571)
  This change can break some naive manual parsing of token trees
  in proc macro code which expect a particular structure after
  `.to_string()`, rather than just arbitrary Rust code.
- [Make `IMPLIED_BOUNDS_ENTAILMENT` into a hard error from a lint]
  (rust-lang/rust#117984)
- [Vec's allocation behavior was changed when collecting some iterators]
  (rust-lang/rust#110353)
  Allocation behavior is currently not specified, nevertheless
  changes can be surprising.
  See [`impl FromIterator for Vec`]
  (https://doc.rust-lang.org/nightly/std/vec/struct.Vec.html#impl-FromIterator%3CT%3E-for-Vec%3CT%3E)
  for more details.
- [Properly reject `default` on free const items]
  (rust-lang/rust#117818)
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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-compiler Relevant to the compiler team, which will review and decide on the PR/issue.
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