Rollup merge of #99689 - dtolnay:write, r=Mark-Simulacrum
Revert `write!` and `writeln!` to late drop temporaries
Closes (on master, but not on beta) #99684 by reverting the `write!` and `writeln!` parts of #96455.
argument position | before<br>#94868 | after<br>#94868 | after<br>#96455 | after<br>this PR | desired<br>(unimplementable)
--- |:---:|:---:|:---:|:---:|:---:
`write!($tmp, "…", …)` | **⸺late** | **⸺late** | *early⸺* | **⸺late** | **⸺late**
`write!(…, "…", $tmp)` | **⸺late** | **⸺late** | *early⸺* | **⸺late** | *early⸺*
`writeln!($tmp, "…", …)` | **⸺late** | **⸺late** | *early⸺* | **⸺late** | **⸺late**
`writeln!(…, "…", $tmp)` | **⸺late** | **⸺late** | *early⸺* | **⸺late** | *early⸺*
`print!("…", $tmp)` | **⸺late** | **⸺late** | *early⸺* | *early⸺* | *early⸺*
`println!("…", $tmp)` | *early⸺* | **⸺late** | *early⸺* | *early⸺* | *early⸺*
`eprint!("…", $tmp)` | **⸺late** | **⸺late** | *early⸺* | *early⸺* | *early⸺*
`eprintln!("…", $tmp)` | *early⸺* | **⸺late**| *early⸺* | *early⸺* | *early⸺*
`panic!("…", $tmp)` | *early⸺* | *early⸺* | *early⸺* | *early⸺* | *early⸺*
"Late drop" refers to dropping temporaries at the nearest semicolon **outside** of the macro invocation.
"Early drop" refers to dropping temporaries inside of the macro invocation.