[beta] reverts

[cuviper]

This reverts two dbg! changes to avoid regressions¹² in the upcoming 1.95 release:

• std: avoid tearing dbg! prints std: avoid tearing dbg! prints #149869
• don't drop arguments' temporaries in dbg! don't drop arguments' temporaries in dbg! #154074
  • ... which was previously backported in [beta] backports #154725

This also reverts a stabilization over a late issue³ of semantics:

• Stabilize assert_matches Stabilize assert_matches #137487

Footnotes

1. 1.95 beta regression: "temporary value dropped while borrowed" #153850 ↩

2. 1.95 beta regression: "lua does not live long enough" #154988 ↩

3. assert_eq/assert_matches vs debug_assert_eq/debug_assert_matches have different temporary scoping behavior #154406 ↩

[rustbot]

Some changes occurred in src/tools/clippy

cc @rust-lang/clippy

The Miri subtree was changed

cc @rust-lang/miri

[rustbot]

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[rustbot]

⚠️ Warning ⚠️

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[rustbot]

Some changes occurred to MIR optimizations

cc @rust-lang/wg-mir-opt

Some changes occurred to the CTFE machinery

cc @RalfJung, @oli-obk, @lcnr

The parser was modified, potentially altering the grammar of (stable) Rust
which would be a breaking change.

cc @fmease