Rollup of 7 pull requests
Successful merges:
- #124655 (Add `-Zfixed-x18`)
- #125693 (Format all source files in `tests/coverage/`)
- #125700 (coverage: Avoid overflow when the MC/DC condition limit is exceeded)
- #125705 (Reintroduce name resolution check for trying to access locals from an inline const)
- #125708 (tier 3 target policy: clarify the point about producing assembly)
- #125715 (remove unneeded extern crate in rmake test)
- #125719 (Extract coverage-specific code out of `compiletest::runtest`)
r? `@ghost`
`@rustbot` modify labels: rollup
debd22da66