This updates all places where match branches check on StatementKind or UseContext.
This doesn't properly implement them, but adds TODOs where they are, and also adds some best
guesses to what they should be in some cases.
Reduce log level used by tracing instrumentation from info to debug
Restore log level to debug to avoid make info log level overly verbose (the uses of instrument attribute modified there, were for the most part a replacement for `debug!`; one use was novel).
Stability oddity with const intrinsics
cc `@RalfJung`
In https://github.com/rust-lang/rust/pull/80699#discussion_r551495670 `@usbalbin` realized we accepted some intrinsics as `const` without a `#[rustc_const_(un)stable]` attribute. I did some digging, and that example works because intrinsics inherit their stability from their parents... including `#[rustc_const_(un)stable]` attributes. While we may want to fix that (not sure, wasn't there just a MCPed PR that caused this on purpose?), we definitely want tests for it, thus this PR adding tests and some fun tracing statements.
Use PlaceRef projection abstractions more consistently in rustc_mir
PlaceRef contains abstractions for dealing with the `projections` array. This PR uses these abstractions more consistently within the `rustc_mir` crate.
See associated issue: rust-lang/rust#80647.
r? `@RalfJung`
replace `#[allow_internal_unstable]` with `#[rustc_allow_const_fn_unstable]` for `const fn`s
`#[allow_internal_unstable]` is currently used to side-step feature gate and stability checks.
While it was originally only meant to be used only on macros, its use was expanded to `const fn`s.
This pr adds stricter checks for the usage of `#[allow_internal_unstable]` (only on macros) and introduces the `#[rustc_allow_const_fn_unstable]` attribute for usage on `const fn`s.
This pr does not change any of the functionality associated with the use of `#[allow_internal_unstable]` on macros or the usage of `#[rustc_allow_const_fn_unstable]` (instead of `#[allow_internal_unstable]`) on `const fn`s (see https://github.com/rust-lang/rust/issues/69399#issuecomment-712911540).
Note: The check for `#[rustc_allow_const_fn_unstable]` currently only validates that the attribute is used on a function, because I don't know how I would check if the function is a `const fn` at the place of the check. I therefore openend this as a 'draft pull request'.
Closesrust-lang/rust#69399
r? @oli-obk
Replace `(Body, DefId)` with `Body` where possible
Follow-up to #77430.
I `grep`-ed for parameter lists in which a `Body` appeared within a few lines of a `DefId`, so it's possible that I missed some cases, but this should be pretty complete. Most of these changes were mechanical, but there's a few places where I started calling things "caller" and "callee" when multiple `DefId`s were in-scope at once. Also, we should probably have a helper function on `Body` that returns a `LocalDefId`. I can do that in this PR or in a follow-up.
These appear along the cleanup path inside functions with
`#[unwind(aborts)]`. We don't const-check the cleanup path anyways,
since const-eval already has "abort-on-panic" semantics and there's
often drops that would otherwise be forbidden, so the check wasn't
really preventing anything anyways.
