1.96.0

⚠️ Breaking Changes

• The layout of `#[repr(Int)]` enums in edge cases involving fields of uninhabited zero-sized types has been fixed, which may change memory layout.
• Unsize-coercing into `Pin<Foo>` where `Foo` doesn't implement `Deref` is now prevented, as it previously produced a type with no useful public API.
• The accidentally stabilized `#![reexport_test_harness_main]` attribute is now gated.
• Errors are reported for return-position-impl-trait-in-traits whose types are too private.
• The `uninhabited_static` lint is now reported in dependencies and is deny-by-default.
• The `-Csoft-float` flag has been removed.
• Importing structs with `::{self [as name]}` (e.g., `struct S {}; use S::{self as Other};`) is no longer permitted because `{self}` imports require a module parent.
• For `export_name`, `link_name`, and `link_section` attributes, if multiple instances are present, the first one now takes precedence (previously behavior might have been different or undefined).
• The minimum external LLVM version required has been updated to 21.
• On `avr` targets, `c_double` is now changed to `f32` to match C's 32-bit `double` type on that target. This is a breaking change for code relying on `c_double` being 64-bit on `avr`.