Rollup of 7 pull requests
Successful merges:
- rust-lang/rust#133477 (Detect tuple structs that are unconstructable due to re-export)
- rust-lang/rust#146929 (compiletest: Remove old-output-capture and become a stage0 bootstrap tool)
- rust-lang/rust#146979 (constify Default on Nanoseconds)
- rust-lang/rust#147092 (Do not compute optimized MIR if code does not type-check.)
- rust-lang/rust#147112 (all 48 keywords in just 300 characters)
- rust-lang/rust#147122 (Fix some crash-test directives)
- rust-lang/rust#147127 (Add a leading dash to linker plugin arguments in the gcc codegen)
r? `@ghost`
`@rustbot` modify labels: rollup
7af913fc90