stop taking references in Relate
Adds a `Copy` bound to `Relate` and changes the type signatures to `T` from `&T`. While the `Copy` bound is not strictly necessary (i.e. the `Clone` bound of `TypeRelation` would be good enough), we don't need non `Copy` types and it simplifies the implementation.
Removes the afaict unused impls for `Vec<ty::PolyExistentialProjection<'tcx>>`, `Rc<T>` and `Box<T>`. If they end up being relevant again the bound of `Relate` can be reduced to `T: Clone`.
This also changes signature of `Binder::skip_binder` to `fn skip_binder(self) -> T`.
`TypeError::ProjectionBoundsLength` was never used and is also removed in this PR.
r? @nikomatsakis maybe 🤔 feel free to reassign
Update Box::from_raw example to generalize better
I know very little about rust, so I saw the example here
```
use std::alloc::{alloc, Layout};
unsafe {
let ptr = alloc(Layout:🆕:<i32>()) as *mut i32;
*ptr = 5;
let x = Box::from_raw(ptr);
}
```
and tried to generalize it by writing,
```
let layout = Layout:🆕:<T>();
let new_obj = unsafe {
let ptr = alloc(layout) as *mut T;
*ptr = obj;
Box::from_raw(ptr)
};
```
for some more complicated `T`, which ended up crashing with SIGSEGV,
because it tried to `drop_in_place` the previous object in `ptr` which is
of course garbage. I think that changing this example to use `.write` instead
would be a good idea to suggest the correct generalization. It is also more
consistent with other documentation items in this file, which use `.write`.
I also added a comment to explain it, but I'm not too attached to that,
and can see it being too verbose in this place.
Bring net/parser.rs up to modern up to date with modern rust patterns
The current implementation of IP address parsing is very unidiomatic; it's full of `if` / `return` / `is_some` / `is_none` instead of `?`, `loop` with manual index tracking; etc. Went through and did and cleanup to try to bring it in line with modern sensibilities.
The obvious concern with making changes like this is "make sure you understand why it's written that way before changing it". Looking through the commit history for this file, there are several much smaller commits that make similar changes (For instance, 3024c1434a, 4f3ab4986e, 79f876495b), and there don't seem to be any commits in the history that indicate that this lack of idiomaticity is related to specific performance needs (ie, there aren't any commits that replace a `for` loop with a `loop` and a manual index count). In fact, the basic shape of the file is essentially unchanged from its initial commit back in 2015.
Made the following changes throughout the IP address parser:
- Replaced all uses of `is_some()` / `is_none()` with `?`.
- "Upgraded" loops wherever possible; ie, replace `while` with `for`, etc.
- Removed all cases of manual index tracking / incrementing.
- Renamed several single-character variables with more expressive names.
- Replaced several manual control flow segments with equivalent adapters (such as `Option::filter`).
- Removed `read_seq_3`; replaced with simple sequences of `?`.
- Parser now reslices its state when consuming, rather than carrying a separate state and index variable.
- `read_digit` now uses `char::to_digit`.
- Added comments throughout, especially in the complex IPv6 parsing logic.
- Added comprehensive local unit tests for the parser to validate these changes.
Added detailed error code explanation for issue E0687 in Rust compiler.
Added proper error explanation for issue E0687 in the Rust compiler.
Error Code E0687
Sub Part of Issue #61137
r? @GuillaumeGomez
We do not test cross-compilation here as the PR builder lacks a sufficiently
recent LLVM to cross-compile to 32-bit linux. Once we bump the minimum LLVM
version to LLVM 9, this can use normal 32-bit linux.
Revert "ci: allow gating gha on everything but macOS"
The macOS issue on GHA's side seems to be fixed, so this is not needed anymore.
r? @Mark-Simulacrum
Serialize all foreign `SourceFile`s into proc-macro crate metadata
Normally, we encode a `Span` that references a foreign `SourceFile` by
encoding information about the foreign crate. When we decode this
`Span`, we lookup the foreign crate in order to decode the `SourceFile`.
However, this approach does not work for proc-macro crates. When we load
a proc-macro crate, we do not deserialzie any of its dependencies (since
a proc-macro crate can only export proc-macros). This means that we
cannot serialize a reference to an upstream crate, since the associated
metadata will not be available when we try to deserialize it.
This commit modifies foreign span handling so that we treat all foreign
`SourceFile`s as local `SourceFile`s when serializing a proc-macro.
All `SourceFile`s will be stored into the metadata of a proc-macro
crate, allowing us to cotinue to deserialize a proc-macro crate without
needing to load any of its dependencies.
Since the number of foreign `SourceFile`s that we load during a
compilation session may be very large, we only serialize a `SourceFile`
if we have also serialized a `Span` which requires it.
There were a few instances of this pattern:
```rust
while index < vec.len() {
let item = &vec[index];
// ...
}
```
These can be indexed at once:
```rust
while let Some(item) = vec.get(index) {
// ...
}
```
Particularly in `ObligationForest::process_obligations`, this mitigates
a codegen regression found with LLVM 11 (#73526).
Made the following changes throughout the IP address parser:
- Replaced all uses of `is_some()` / `is_none()` with `?`.
- "Upgraded" loops wherever possible; ie, replace `while` with `for`, etc.
- Removed all cases of manual index tracking / incrementing.
- Renamed several single-character variables with more expressive names.
- Replaced several manual control flow segments with equivalent adapters (such as `Option::filter`).
- Removed `read_seq_3`; replaced with simple sequences of `?`.
- Parser now reslices its state when consuming, rather than carrying a separate state and index variable.
- `read_digit` now uses `char::to_digit`.
- Removed unnecessary casts back and forth between u8 and u32
- Added comments throughout, especially in the complex IPv6 parsing logic.
- Added comprehensive local unit tests for the parser to validate these changes.
bootstrap: Configurable musl libdir
Make it possible to customize the location of musl libdir using
musl-libdir in config.toml, e.g., to use lib64 instead of lib.
