Rust

Language

• Stabilize &mut, *mut, &Cell, and *const Cell in const.
• Allow creating references to statics in const initializers.
• Implement raw lifetimes and labels ('r#ident).
• Define behavior when atomic and non-atomic reads race.
• Non-exhaustive structs may now be empty.
• Disallow implicit coercions from places of type !
• const extern functions can now be defined for other calling conventions.
• Stabilize expr_2021 macro fragment specifier in all editions.
• The non_local_definitions lint now fires on less code and warns b

Language

• Don't make statement nonterminals match pattern nonterminals
• Patterns matching empty types can now be omitted in common cases
• Enforce supertrait outlives obligations when using trait impls
• addr_of(_mut)! macros and the newly stabilized &raw (const|mut) are now safe to use with all static items
• size_of_val_raw: for length 0 this is safe to call
• Reorder trait bound modifiers after for<...> binder in trait bounds
• Stabilize opaque type precise capturing (RFC 3617)
• Stabilize &raw const and &raw mut operators (RFC 2582)
• Stabilize unsafe extern blocks (RF

Language

• Abort on uncaught panics in extern "C" functions.
• Fix ambiguous cases of multiple & in elided self lifetimes.
• Stabilize #[expect] for lints (RFC 2383), like #[allow] with a warning if the lint is not fulfilled.
• Change method resolution to constrain hidden types instead of rejecting method candidates.
• Bump elided_lifetimes_in_associated_constant to deny.
• offset_from: always allow pointers to point to the same address.
• Allow constraining opaque types during subtyping in the trait system.
• Allow constraining opaque types during various unsizing casts.

• Fix miscompilation in the jump threading MIR optimization when comparing floats
• Revert changes to the dead_code lint from 1.80.0

Language

• Document maximum allocation size
• Allow zero-byte offsets and ZST read/writes on arbitrary pointers
• Support C23's variadics without a named parameter
• Stabilize exclusive_range_pattern feature
• Guarantee layout and ABI of Result in some scenarios

Compiler

• Update cc crate to v1.0.97 allowing additional spectre mitigations on MSVC targets
• Allow field reordering on types marked repr(packed(1))
• Add a lint against never type fallback affecting unsafe code
• Disallow cast with trailing braced macro in let-else
• Expand for_loops_over_fallibles

Language

• Stabilize inline const {} expressions.
• Prevent opaque types being instantiated twice with different regions within the same function.
• Stabilize WebAssembly target features that are in phase 4 and 5.
• Add the redundant_lifetimes lint to detect lifetimes which are semantically redundant.
• Stabilize the unnameable_types lint for public types that can't be named.
• Enable debuginfo in macros, and stabilize -C collapse-macro-debuginfo and #[collapse_debuginfo].
• Propagate temporary lifetime extension into if and match expressions.
• Restrict promotion of const fn calls.

Language

• Stabilize #[cfg(target_abi = ...)]
• Stabilize the #[diagnostic] namespace and #[diagnostic::on_unimplemented] attribute
• Make async-fn-in-trait implementable with concrete signatures
• Make matching on NaN a hard error, and remove the rest of illegal_floating_point_literal_pattern
• static mut: allow mutable reference to arbitrary types, not just slices and arrays
• Extend invalid_reference_casting to include references casting to bigger memory layout
• Add non_contiguous_range_endpoints lint for singleton gaps after exclusive ranges
• Add wasm_c_abi lint for use of older wasm-bind

• CVE-2024-24576: fix escaping of Windows batch file arguments in std::process::Command

• Revert stripping debuginfo by default for Windows This fixes a regression in 1.77 by reverting to the previous default. Platforms other than Windows are not affected.
• Internal: Fix heading anchor rendering in doc pages

Language

• Reveal opaque types within the defining body for exhaustiveness checking.
• Stabilize C-string literals.
• Stabilize THIR unsafeck.
• Add lint static_mut_refs to warn on references to mutable statics.
• Support async recursive calls (as long as they have indirection).
• Undeprecate lint unstable_features and make use of it in the compiler.
• Make inductive cycles in coherence ambiguous always.
• Get rid of type-driven traversal in const-eval interning, only as a future compatiblity lint for now.
• Deny braced macro invocations in let-else.

Compiler

• In

Language

• Document Rust ABI compatibility between various types
• Also: guarantee that char and u32 are ABI-compatible
• Warn against ambiguous wide pointer comparisons

Compiler

• Lint pinned #[must_use] pointers (in particular, Box<T> where T is #[must_use]) in unused_must_use.
• Soundness fix: fix computing the offset of an unsized field in a packed struct
• Soundness fix: fix dynamic size/align computation logic for packed types with dyn Trait tail
• Add $message_type field to distinguish json diagnostic outputs
• Enable Rust to use the EHCont security fea