Rollup of 13 pull requests

Successful merges:

 - #140434 (rustdoc: Allow multiple references to a single footnote)
 - #142372 (Improve `--remap-path-prefix` documentation)
 - #142741 (Fix unsoundness in some tests)
 - #144515 (Implement `ptr_cast_array`)
 - #144727 (Add tracing to resolve-related functions)
 - #144959 (fix(unicode-table-generator): fix duplicated unique indices)
 - #145179 (Avoid abbreviating "numerator" as "numer", to allow catching typo "numer" elsewhere)
 - #145250 (Add regression test for a former ICE involving helper attributes containing interpolated tokens)
 - #145266 (Reduce some queries around associated items)
 - #145299 (doc test: fix mpsc.rs try_send doc test)
 - #145323 (Port the `#[linkage]` attribute to the new attribute system)
 - #145361 (Suppress wrapper suggestion when expected and actual ty are the same adt and the variant is unresolved)
 - #145372 (resolve: Miscellaneous cleanups)

r? `@ghost`
`@rustbot` modify labels: rollup

Rollup merge of #142741 - a1phyr:fix_unsoundness, r=Mark-Simulacrum

Fix unsoundness in some tests

These tests were marked uninit bytes as initilized, which is unsound. Use initialized `MaybeUninit` instead.

…ulacrum

Fix unsoundness in some tests

These tests were marked uninit bytes as initilized, which is unsound. Use initialized `MaybeUninit` instead.