bors 61469b682c Auto merge of #96490 - dtolnay:writetmpbackport, r=Mark-Simulacrum ...

Make [e]println macros eagerly drop temporaries (for backport)

This PR extracts the subset of #96455 which is only the parts necessary for fixing the 1.61-beta regressions in #96434.

My larger PR #96455 contains a few other changes relative to the pre-#94868 behavior; those are not necessary to backport into 1.61.

argument position | before #94868 | after #94868 | after this PR
--- |:---:|:---:|:---:
`write!($tmp, "…", …)` | 😡 | 😡 | 😡
`write!(…, "…", $tmp)` | 😡 | 😡 | 😡
`writeln!($tmp, "…", …)` | 😡 | 😡 | 😡
`writeln!(…, "…", $tmp)` | 😡 | 😡 | 😡
`print!("…", $tmp)` | 😡 | 😡 | 😡
`println!("…", $tmp)` | 😺 | 😡 | 😺
`eprint!("…", $tmp)` | 😡 | 😡 | 😡
`eprintln!("…", $tmp)` | 😺 | 😡 | 😺
`panic!("…", $tmp)` | 😺 | 😺 | 😺

2022-05-01 03:18:53 +00:00

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alloc

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backtrace @ b02ed04a7e

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core

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panic_abort

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panic_unwind

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portable-simd

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proc_macro

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profiler_builtins

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rtstartup

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rustc-std-workspace-alloc

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rustc-std-workspace-core

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rustc-std-workspace-std

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std

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stdarch @ d215afe9d1

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test

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unwind

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