This allows us to:
- Handle precise Places captured by a closure directly in MIR. Handling
captures in MIR is easier since we can rely on/ tweak PlaceBuilder to
generate `mir::Place`s that resemble how we store captures (`hir::Place`).
- Allows us to handle `let _ = x` case when feature `capture_disjoint_fields`
is enabled directly in MIR. This is required to be done in MIR since
patterns are desugared in MIR.
reverse binding order in matches to allow the subbinding of copyable fields in bindings after @
Fixes#69971
### TODO
- [x] Regression tests
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.
There's a cleaner way of doing this, but it involves passing
`WithOptConstParam` around in more places. We're going to try to explore
different approaches before committing to that.
Fixes#74053Fixes#55721
This PR adds a new lint `CONST_ITEM_MUTATION`.
Given an item `const FOO: SomeType = ..`, this lint fires on:
* Attempting to write directly to a field (`FOO.field = some_val`) or
array entry (`FOO.array_field[0] = val`)
* Taking a mutable reference to the `const` item (`&mut FOO`), including
through an autoderef `FOO.some_mut_self_method()`
The lint message explains that since each use of a constant creates a
new temporary, the original `const` item will not be modified.
