Update Rust to v1.57.0

[renovate]

This PR contains the following updates:

Package	Update	Change
rust	minor	1.56.1 -> 1.57.0

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Release Notes

rust-lang/rust

v1.57.0

Compare Source

==========================

Language

• Macro attributes may follow #[derive] and will see the original (pre-cfg) input.
• Accept curly-brace macros in expressions, like m!{ .. }.method() and m!{ .. }?.
• Allow panicking in constant evaluation.

Compiler

• Create more accurate debuginfo for vtables.
• Add armv6k-nintendo-3ds at Tier 3*.
• Add armv7-unknown-linux-uclibceabihf at Tier 3*.
• Add m68k-unknown-linux-gnu at Tier 3*.
• Add SOLID targets at Tier 3*: aarch64-kmc-solid_asp3, armv7a-kmc-solid_asp3-eabi, armv7a-kmc-solid_asp3-eabihf

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

Libraries

• Avoid allocations and copying in Vec::leak
• Add #[repr(i8)] to Ordering
• Optimize File::read_to_end and read_to_string
• Update to Unicode 14.0
• Many more functions are marked #[must_use], producing a warning
  when ignoring their return value. This helps catch mistakes such as expecting
  a function to mutate a value in place rather than return a new value.

Stabilised APIs

• [T; N]::as_mut_slice
• [T; N]::as_slice
• [collections::TryReserveError][collections::TryReserveError]
• [HashMap::try_reserve][HashMap::try_reserve]
• [HashSet::try_reserve][HashSet::try_reserve]
• [String::try_reserve][String::try_reserve]
• [String::try_reserve_exact][String::try_reserve_exact]
• [Vec::try_reserve][Vec::try_reserve]
• [Vec::try_reserve_exact][Vec::try_reserve_exact]
• [VecDeque::try_reserve][VecDeque::try_reserve]
• [VecDeque::try_reserve_exact][VecDeque::try_reserve_exact]
• [Iterator::map_while][Iterator::map_while]
• [iter::MapWhile][iter::MapWhile]
• [proc_macro::is_available][proc_macro::is_available]
• [Command::get_program][Command::get_program]
• [Command::get_args][Command::get_args]
• [Command::get_envs][Command::get_envs]
• [Command::get_current_dir][Command::get_current_dir]
• [CommandArgs][CommandArgs]
• [CommandEnvs][CommandEnvs]

These APIs are now usable in const contexts:

• [hint::unreachable_unchecked]

Cargo

• Stabilize custom profiles

Compatibility notes

Internal changes

These changes provide no direct user facing benefits, but represent significant
improvements to the internals and overall performance of rustc
and related tools.

• Added an experimental backend for codegen with libgccjit.

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Configuration

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[Turbo87]

@bors r+

[bors]

📌 Commit 103178a has been approved by Turbo87

[bors]

⌛ Testing commit 103178a with merge 132745e...

[bors]

☀️ Test successful - checks-actions
Approved by: Turbo87
Pushing 132745e to master...