Separate const prop lints from optimizations
r? `@oli-obk`
Separates lints and optimizations during const prop by moving the lints into their own file and checking them during post borrowck cleanup.
Thanks to `@oli-obk` for mentoring me.
This change was made as per suspicion that this struct was never renamed after consistent use of DropCk.
This also clarifies the meaning behind the name of this structure.
Change Thir to lazily create constants
To allow `AbstractConst`s to work with the previous thir changes we made and those we want to make, i.e. to avoid problems due to `ValTree` and `ConstValue` conversions, we instead switch to a thir representation for constants that allows us to lazily create constants.
r? `@oli-obk`
Properly track `ImplObligations`
Instead of probing for all possible `impl`s that could have caused an
`ImplObligation`, keep track of its `DefId` and obligation spans for
accurate error reporting.
Follow to #89580. Addresses #89418.
Before this fix, the debuginfo for the fields was generated from the
struct defintion of Box<T>, but (at least at the moment) the compiler
pretends that Box<T> is just a (fat) pointer, so the fields need to be
`pointer` and `vtable` instead of `__0: Unique<T>` and `__1: Allocator`.
This is meant as a temporary mitigation until we can make sure that
simply treating Box as a regular struct in debuginfo does not cause too
much breakage in the ecosystem.
Instead of probing for all possible impls that could have caused an
`ImplObligation`, keep track of its `DefId` and obligation spans for
accurate error reporting.
Follow up to #89580. Addresses #89418.
Remove some unnecessary clones.
Tweak output for auto trait impl obligations.
add module-level documentation for vec's in-place iteration
As requested in the last libs team meeting and during previous reviews.
Feel free to point out any gaps you encounter, after all non-obvious things may with hindsight seem obvious to me.
r? `@yaahc`
CC `@steffahn`
Rollup of 5 pull requests
Successful merges:
- #94249 (Better errors when a Copy impl on a Struct is not self-consistent)
- #95069 (Fix auto traits in rustdoc)
- #95221 (interpret/memory: simplify check_and_deref_ptr)
- #95225 (remove `[async output]` from `impl Future` pretty-printing)
- #95238 (Stop emitting E0026 for struct enums with underscores)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
This enhances documentation with these details and extends the validator to check these requirements
more thoroughly. As a part of this, we add a new `Deaggregated` phase, and rename other phases so
that their names more naturally correspond to what they represent.
interpret/memory: simplify check_and_deref_ptr
*Finally* I saw a way to make this code simpler. The odd preprocessing in `let ptr_or_addr =` has bothered me since forever, but it actually became unnecessary in the last provenance refactoring. :)
This also leads to slightly more explicit error messages as a nice side-effect. 🎉
r? `@oli-obk`
Better errors when a Copy impl on a Struct is not self-consistent
As discovered in a Zulip thread with `@nnethercote` and `@Mark-Simulacrum,` it's not immediately obvious why a field on an ADT doesn't implement `Copy`. This PR attempts to give slightly more detailed information by spinning up a fulfillment context to try to dig down and discover transitive fulfillment errors that cause `is_copy_modulo_regions` to fail on a ADT field.
The error message still kinda sucks, but should only show up in the case that an existing error message was totally missing... so I think it's a good compromise for now?
By reversing the arguments we achieve several clarifications:
- The function closely resembles `cast` but with an argument to
initialized the metadata. This is easier to teach and answers an long
outstanding question that had restricted cast to `Sized` targets
initially. See multiples reviews of
<https://github.com/rust-lang/rust/pull/47631>
- The 'object identity', in the form or provenance, is now preserved
from the call receiver to the result. This helps explain the method as
a builder-style, instead of some kind of setter that would modify
something in-place. Ensuring that the result has the identity of the
`self` argument is also beneficial for an intuition of effects.
- An outstanding concern, 'Correct argument type', is avoided by not
committing to any specific argument type. This is consistent with cast
which does not require its receiver to be a raw address.
diagnostics: do not suggest `fn foo({ <body> }`
Instead of suggesting that the body always replace the last character on the line, presuming it must be a semicolon, the parser should instead check what the last character is, and append the body if it is anything else.
Fixes#83104
Rename `~const Drop` to `~const Destruct`
r? `@oli-obk`
Completely switching to `~const Destructible` would be rather complicated, so it seems best to add it for now and wait for it to be backported to beta in the next release.
The rationale is to prevent complications such as #92149 and #94803 by introducing an entirely new trait. And `~const Destructible` reads a bit better than `~const Drop`. Name Bikesheddable.
