use precompiled rustc for non-dist builders
Makes non-dist builders to use precompiled CI rustc by default if they are available for the target triple.
As we are going to make `rust.download-rustc=if-unchanged` default option with https://github.com/rust-lang/rust/pull/119899, we need to make sure `if-unchanged` logic never breaks and works as expected.
As an addition, this will significantly improve the build times on CI when there's no change on the compiler.
blocker for #119899
try-job: x86_64-gnu-nopt
try-job: aarch64-apple
Drop compiletest legacy directive check
Sufficient time has passed (> 6 months) since we migrated from `//` to `//`@`,` so let's drop the
legacy directive check as it causes friction due to false positives.
As a side-effect, dropping the legacy directive check simplifies the directive scanning logic.
The legacy directive check was originally added to help people be aware of the migration.
Blocker for #131382 cc `@ehuss.`
Can be reviewed by any compiler/bootstrap reviewer.
[rustdoc] Remove intra-doc links dead code
While working on https://github.com/rust-lang/rust/pull/130278, I wondered what `resolve_display_text` was doing. I removed it and ran all rustdoc tests, and nothing failed. Are some intra-doc links tests missing or is it really dead code? Couldn't figure it out.
r? `@notriddle`
Sufficient time has passed (> 6 months) since we migrated from `//` to
`//@`, so let's drop the legacy directive check as it causes friction
due to false positives.
[Coverage][MCDC] Adapt mcdc to llvm 19
Related issue: #126672
Also finish task 4 at #124144
[llvm #82448](https://github.com/llvm/llvm-project/pull/82448) has introduced some break changes into mcdc, causing incompatibility between llvm 18 and 19. This draft adapts to that change and gives up supporting for llvm-18.
`Deref`/`DerefMut` can be useful, but they can also obfuscate. I don't
think they're worth it for `RegionConstraintCollector`. They're also not
present on the similar types `OpaqueTypeTable` and `TypeVariableTable`.
`LeakCheck` can own `mini_graph` and `rcc` instead of holding references
to them. This requires inlining `assign_scc_value` to avoid a borrowck
error, but that's fine because it has a single call site.
It's a weird method, and used weirdly:
- It's on `RegionConstraintCollector` but operates on
`RegionConstraintStorage`. So at both call sites we create a temporary
`RegionConstraintCollector`, using `with_log`, to call it.
- It `take`s just two of the six fields in `RegionConstraintStorage`.
At one of the two call sites we unnecessarily clone the entire
`RegionConstraintStorage` just to take those two fields.
This commit just inlines and removes it. We no longer need to `take` the
two fields, we can just use them directly.
`OutlivesEnvironment::new` can call `OutlivesEnvironment::with_bounds`
with an empty `extra_bounds`. And once that's done,
`OutlivesEnvironmentBuilder` has a single use and can be inlined and
removed into `OutlivesEnvironment::with_bounds`.
