Fix missing impl trait display as ret type
I need to convert a `TraitPredicate` into a `TraitBound` to get the returned impl trait. So far, didn't find how or even if it was the good way to do it.
cc @eddyb @oli-obk (since you're the one behind the change apparently 😉)
CTFE engine refactor
* Value gets renamed to `Operand`, so that now `interpret::{Place, Operand}` are the "dynamic" versions of `mir::{Place, Operand}`.
* `Operand` and `Place` share the data for their "stuff is in memory"-base in a new type, `MemPlace`. This also makes it possible to give some more precise types in other areas. Both `Operand` and `MemPlace` have methods available to project into fields (and other kinds of projections) without causing further allocations.
* The type for "a `Scalar` or a `ScalarPair`" is called `Value`, and again used to give some more precise types.
* All of these have versions with an attached layout, so that we can more often drag the layout along instead of recomputing it. This lets us get rid of `PlaceExtra::Downcast`. `MPlaceTy` and `PlaceTy` can only be constructed in place.rs, making sure the layout is handled properly. (The same should eventually be done for `ValTy` and `OpTy`.)
This is used to check, when copying an operand to a place, that the sizes match (which caught a bunch of bugs).
* All the high-level functions to write typed memory take a `Place`, and live in `place.rs`. All the high-level typed functions to read typed memory take an `Operand`, and live in `operands.rs`.
* Remove `cur_frame` and handling of signedess from memory (catching a bug in the float casting code).
* [Only functional change] Enable sanity check to recurse below dyn traits and slices.
r? @oli-obk
Cc @eddyb
During the sanity check, we keep track of the path we are below in a `Vec`. We
avoid cloning that `Vec` unless we hit a pointer indirection. The `String`
representation is only computed when validation actually fails.
Exhaustive integer matching
This adds a new feature flag `exhaustive_integer_patterns` that enables exhaustive matching of integer types by their values. For example, the following is now accepted:
```rust
#![feature(exhaustive_integer_patterns)]
#![feature(exclusive_range_pattern)]
fn matcher(x: u8) {
match x { // ok
0 .. 32 => { /* foo */ }
32 => { /* bar */ }
33 ..= 255 => { /* baz */ }
}
}
```
This matching is permitted on all integer (signed/unsigned and char) types. Sensible error messages are also provided. For example:
```rust
fn matcher(x: u8) {
match x { //~ ERROR
0 .. 32 => { /* foo */ }
}
}
```
results in:
```
error[E0004]: non-exhaustive patterns: `32u8...255u8` not covered
--> matches.rs:3:9
|
6 | match x {
| ^ pattern `32u8...255u8` not covered
```
This implements https://github.com/rust-lang/rfcs/issues/1550 for https://github.com/rust-lang/rust/issues/50907. While there hasn't been a full RFC for this feature, it was suggested that this might be a feature that obviously complements the existing exhaustiveness checks (e.g. for `bool`) and so a feature gate would be sufficient for now.
Rollup of 17 pull requests
Successful merges:
- #53030 (Updated RELEASES.md for 1.29.0)
- #53104 (expand the documentation on the `Unpin` trait)
- #53213 (Stabilize IP associated constants)
- #53296 (When closure with no arguments was expected, suggest wrapping)
- #53329 (Replace usages of ptr::offset with ptr::{add,sub}.)
- #53363 (add individual docs to `core::num::NonZero*`)
- #53370 (Stabilize macro_vis_matcher)
- #53393 (Mark libserialize functions as inline)
- #53405 (restore the page title after escaping out of a search)
- #53452 (Change target triple used to check for lldb in build-manifest)
- #53462 (Document Box::into_raw returns non-null ptr)
- #53465 (Remove LinkMeta struct)
- #53492 (update lld submodule to include RISCV patch)
- #53496 (Fix typos found by codespell.)
- #53521 (syntax: Optimize some literal parsing)
- #53540 (Moved issue-53157.rs into src/test/ui/consts/const-eval/)
- #53551 (Avoid some Place clones.)
Failed merges:
r? @ghost
This commit adds a normalization for line and column numbers in stderr
files where the line/col is from the source directory rather than
the test itself - thereby removing the need to update tests as
compiler source changes.
Change `Rc::inc_{weak,strong}` to better hint optimization to LLVM
As discussed in #13018, `Rc::inc_strong` and `Rc::inc_weak` are changed to allow compositions of `clone` and `drop` to be better optimized. Almost entirely as in [this comment](https://github.com/rust-lang/rust/issues/13018#issuecomment-408642184), except that `abort` on zero is added so that a `drop(t.clone())` does not produce a zero check followed by conditional deallocation.
This is different from #21418 in that it doesn't rely on `assume`, avoiding the prohibitive compilation slowdown.
[Before and after IR](https://gist.github.com/hermord/266e55451b7fe0bb8caa6e35d17c86e1).
`fn resolve_legacy_scope` can now resolve only to `macro_rules!` items,
`fn resolve_lexical_macro_path_segment` is for everything else - modularized macros, preludes
The Great Generics Generalisation: HIR Followup
Addresses the final comments in #48149.
r? @eddyb, but there are a few things I have yet to clean up. Making the PR now to more easily see when things break.
cc @yodaldevoid
