disallow repr() on invalid items by folkertdev · Pull Request #133925 · rust-lang/rust (original) (raw)

Upstream changes relative to 1.85.1:

Version 1.86.0 (2025-04-03)

Language

• [Stabilize upcasting trait objects to supertraits.] (rust-lang/rust#134367)
• [Allow safe functions to be marked with the #[target_feature] attribute.] (rust-lang/rust#134090)
• [The missing_abi lint now warns-by-default.] (rust-lang/rust#132397)
• Rust now lints about double negations, to catch cases that might have intended to be a prefix decrement operator (--x) as written in other languages. This was previously a clippy lint, clippy::double_neg, and is [now available directly in Rust as double_negations.] (rust-lang/rust#126604)
• [More pointers are now detected as definitely not-null based on their alignment in const eval.] (rust-lang/rust#133700)
• [Empty repr() attribute applied to invalid items are now correctly rejected.] (rust-lang/rust#133925)
• [Inner attributes #![test] and #![rustfmt::skip] are no longer accepted in more places than intended.] (rust-lang/rust#134276)

Compiler

• [Debug-assert that raw pointers are non-null on access.] (rust-lang/rust#134424)
• [Change -O to mean -C opt-level=3 instead of -C opt-level=2 to match Cargo's defaults.] (rust-lang/rust#135439)
• [Fix emission of overflowing_literals under certain macro environments.] (rust-lang/rust#136393)

Platform Support

• [Replace i686-unknown-redox target with i586-unknown-redox.] (rust-lang/rust#136698)
• [Increase baseline CPU of i686-unknown-hurd-gnu to Pentium 4.] (rust-lang/rust#136700)
• New tier 3 targets:
  • [{aarch64-unknown,x86_64-pc}-nto-qnx710_iosock] (rust-lang/rust#133631). For supporting Neutrino QNX 7.1 with io-socket network stack.
  • [{aarch64-unknown,x86_64-pc}-nto-qnx800] (rust-lang/rust#133631). For supporting Neutrino QNX 8.0 (no_std-only).
  • [{x86_64,i686}-win7-windows-gnu] (rust-lang/rust#134609). Intended for backwards compatibility with Windows 7. {x86_64,i686}-win7-windows-msvc are the Windows MSVC counterparts that already exist as Tier 3 targets.
  • amdgcn-amd-amdhsa.
  • x86_64-pc-cygwin.
  • [{mips,mipsel}-mti-none-elf] (rust-lang/rust#135074). Initial bare-metal support.
  • m68k-unknown-none-elf.
  • [armv7a-nuttx-{eabi,eabihf}, aarch64-unknown-nuttx, and thumbv7a-nuttx-{eabi,eabihf}] (rust-lang/rust#135757).

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

Libraries

• The type of FromBytesWithNulError in CStr::from_bytes_with_nul(bytes: &[u8]) -> Result<&Self, FromBytesWithNulError> was [changed from an opaque struct to an enum] (rust-lang/rust#134143), allowing users to examine why the conversion failed.
• [Remove RustcDecodable and RustcEncodable.] (rust-lang/rust#134272)
• [Deprecate libtest's --logfile option.] (rust-lang/rust#134283)
• [On recent versions of Windows, std::fs::remove_file will now remove read-only files.] (rust-lang/rust#134679)

Stabilized APIs

• [{float}::next_down] (https://doc.rust-lang.org/stable/std/primitive.f64.html#method.next_down)
• [{float}::next_up] (https://doc.rust-lang.org/stable/std/primitive.f64.html#method.next_up)
• [<[_]>::get_disjoint_mut] (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.get_disjoint_mut)
• [<[_]>::get_disjoint_unchecked_mut] (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.get_disjoint_unchecked_mut)
• [slice::GetDisjointMutError] (https://doc.rust-lang.org/stable/std/slice/enum.GetDisjointMutError.html)
• [HashMap::get_disjoint_mut] (https://doc.rust-lang.org/std/collections/hash_map/struct.HashMap.html#method.get_disjoint_mut)
• [HashMap::get_disjoint_unchecked_mut] (https://doc.rust-lang.org/std/collections/hash_map/struct.HashMap.html#method.get_disjoint_unchecked_mut)
• [NonZero::count_ones] (https://doc.rust-lang.org/stable/std/num/struct.NonZero.html#method.count_ones)
• [Vec::pop_if] (https://doc.rust-lang.org/std/vec/struct.Vec.html#method.pop_if)
• [sync::Once::wait] (https://doc.rust-lang.org/stable/std/sync/struct.Once.html#method.wait)
• [sync::Once::wait_force] (https://doc.rust-lang.org/stable/std/sync/struct.Once.html#method.wait_force)
• [sync::OnceLock::wait] (https://doc.rust-lang.org/stable/std/sync/struct.OnceLock.html#method.wait)

These APIs are now stable in const contexts:

• [hint::black_box] (https://doc.rust-lang.org/stable/std/hint/fn.black_box.html)
• [io::Cursor::get_mut] (https://doc.rust-lang.org/stable/std/io/struct.Cursor.html#method.get_mut)
• [io::Cursor::set_position] (https://doc.rust-lang.org/stable/std/io/struct.Cursor.html#method.set_position)
• [str::is_char_boundary] (https://doc.rust-lang.org/stable/std/primitive.str.html#method.is_char_boundary)
• [str::split_at] (https://doc.rust-lang.org/stable/std/primitive.str.html#method.split_at)
• [str::split_at_checked] (https://doc.rust-lang.org/stable/std/primitive.str.html#method.split_at_checked)
• [str::split_at_mut] (https://doc.rust-lang.org/stable/std/primitive.str.html#method.split_at_mut)
• [str::split_at_mut_checked] (https://doc.rust-lang.org/stable/std/primitive.str.html#method.split_at_mut_checked)

Cargo

• [When merging, replace rather than combine configuration keys that refer to a program path and its arguments.] (rust-lang/cargo#15066)
• [Error if both --package and --workspace are passed but the requested package is missing.] (rust-lang/cargo#15071) This was previously silently ignored, which was considered a bug since missing packages should be reported.
• [Deprecate the token argument in cargo login to avoid shell history leaks.] (rust-lang/cargo#15057)
• [Simplify the implementation of SourceID comparisons.] (rust-lang/cargo#14980) This may potentially change behavior if the canonicalized URL compares differently in alternative registries.

Rustdoc

• [Add a sans-serif font setting.] (rust-lang/rust#133636)

Compatibility Notes

• [The wasm_c_abi future compatibility warning is now a hard error.] (rust-lang/rust#133951) Users of wasm-bindgen should upgrade to at least version 0.2.89, otherwise compilation will fail.
• [Remove long-deprecated no-op attributes #![no_start] and #![crate_id].] (rust-lang/rust#134300)
• [The future incompatibility lint cenum_impl_drop_cast has been made into a hard error.] (rust-lang/rust#135964) This means it is now an error to cast a field-less enum to an integer if the enum implements Drop.
• [SSE2 is now required for "i686" 32-bit x86 hard-float targets; disabling it causes a warning that will become a hard error eventually.] (rust-lang/rust#137037) To compile for pre-SSE2 32-bit x86, use a "i586" target instead.

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.

• [Build the rustc on AArch64 Linux with ThinLTO + PGO.] (rust-lang/rust#133807) The ARM 64-bit compiler (AArch64) on Linux is now optimized with ThinLTO and PGO, similar to the optimizations we have already performed for the x86-64 compiler on Linux. This should make it up to 30% faster.