Rollup of 3 pull requests
Successful merges:
- #63872 (Document platform-specific behavior of the iterator returned by std::fs::read_dir)
- #64250 (save-analysis: Nest typeck tables when processing functions/methods)
- #64472 (Don't mark expression with attributes as not needing parentheses)
Failed merges:
r? @ghost
save-analysis: Nest typeck tables when processing functions/methods
Fixes an issue where we did not nest tables correctly when resolving
associated types in formal argument/return type positions.
This was the minimized reproduction case that I tested the fix on:
```rust
pub trait Trait {
type Assoc;
}
pub struct A;
pub fn func() {
fn _inner1<U: Trait>(_: U::Assoc) {}
fn _inner2<U: Trait>() -> U::Assoc { unimplemented!() }
impl A {
fn _inner1<U: Trait>(self, _: U::Assoc) {}
fn _inner2<U: Trait>(self) -> U::Assoc { unimplemented!() }
}
}
```
using `debug_assertions`-enabled rustc and by additionally passing `-Zsave-analysis`.
Unfortunately the original assertion fired is a *debug* one and from what I can tell we don't run the tests with these on, so I'm not adding a test here. If I missed it and there is a way to run tests with these on, I'd love to add a test case for this.
Closes#63663Closes#50328Closes#43982
Cleanup handling of hygiene for built-in macros
This makes most identifiers generated by built-in macros use def-site hygiene, not only the ones that previously used gensyms.
* `ExtCtxt::ident_of` now takes a `Span` and is preferred to `Ident::{from_str, from_str_and_span}`
* Remove `Span::with_legacy_ctxt`
* `assert` now uses call-site hygiene because it needs to resolve `panic` unhygienically.
* `concat_idents` now uses call-site hygiene because it wouldn't be very useful with def-site hygiene.
* everything else is moved to def-site hygiene
r? @petrochenkov
def_collector: Do not ICE on attributes on unnamed fields
The primary issue here is that the expansion infra needs to visit a field in isolation, and fields don't know their own indices during expansion, so they have to be kept in some other place (e.g. `struct Definitions`).
Fixes https://github.com/rust-lang/rust/issues/64385
Use `panic::set_hook` to print the ICE message
This allows custom frontends and backends to override the hook with their own, for example to point people to a different issue tracker.
ICE messages are printed in a slightly different order now. Nightly prints:
```
thread 'rustc' panicked at 'called `Option::unwrap()` on a `None` value', src/libcore/option.rs:347:21
note: Run with `RUST_BACKTRACE=1` environment variable to display a backtrace.
error: aborting due to 2 previous errors
Some errors have detailed explanations: E0277, E0658.
For more information about an error, try `rustc --explain E0277`.
error: internal compiler error: unexpected panic
note: the compiler unexpectedly panicked. this is a bug.
note: we would appreciate a bug report: https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.md#bug-reports
note: rustc 1.36.0-nightly (08bfe1612 2019-05-02) running on x86_64-unknown-linux-gnu
```
After this PR, rustc prints:
```
thread 'rustc' panicked at 'called `Option::unwrap()` on a `None` value', src/libcore/option.rs:347:21
note: Run with `RUST_BACKTRACE=1` environment variable to display a backtrace.
error: internal compiler error: unexpected panic
note: the compiler unexpectedly panicked. this is a bug.
note: we would appreciate a bug report: https://github.com/rust-lang/rust/blob/master/CONTRIBUTING.md#bug-reports
note: rustc 1.36.0-dev running on x86_64-unknown-linux-gnu
error: aborting due to 2 previous errors
Some errors have detailed explanations: E0277, E0658.
For more information about an error, try `rustc --explain E0277`.
```
Provide a span if main function is not present in crate
Unfortunately, the diagnostic machinery does not cope well with an empty
span which can happen if the crate is empty, in which case we merely set
a spanless note.
Tests are already updated for this change, so a dedicated test is not added.
Resolves#36561.
Unfortunately, the diagnotic machinery does not cope well with an empty
span which can happen if the crate is empty, in which case we merely set
a spanless note.
Shrink `ObligationCauseCode`
These commits reduce the size of `ObligationCauseCode` from 56 bytes to 32 bytes on 64-bit. This reduces instruction counts on various benchmarks by up to 1%, due to less `memcpy`ing.
[Place 2.0] Convert Place's projection to a boxed slice
This is still work in progress, it's not compiling right now I need to review a bit more to see what's going on but wanted to open the PR to start discussing it.
r? @oli-obk
Avoid more `Symbol`-to-string operations
These commits avoid various `Symbol`-to-string conversions, by doing more operations directly on `Symbol`s. This requires adding a few more static `Symbol`s to the binary.
r? @petrochenkov
check_match: refactor + improve non-exhaustive diagnostics for default binding modes
Refactor `check_match` a bit with more code-reuse and improve the diagnostics for a non-exhaustive pattern match by peeling off any references from the scrutinee type so that the "defined here" label is added in more cases. For example:
```rust
error[E0004]: non-exhaustive patterns: `&mut &B` not covered
--> foo.rs:4:11
|
1 | enum E { A, B }
| ---------------
| | |
| | not covered
| `E` defined here
...
4 | match x {
| ^ pattern `&mut &B` not covered
|
= help: ensure that all possible cases are being handled, possibly by adding wildcards or more match arms
```
Moreover, wrt. "defined here", we give irrefutable pattern matching (i.e. in `let`, `for`, and `fn` parameters) a more consistent treatment in line with `match`.
r? @estebank
This commit changes the HIR lowering around `await` so that temporary
lifetimes are extended. Previously, await was lowered as:
```rust
{
let mut pinned = future;
loop {
match ::std::future::poll_with_tls_context(unsafe {
<::std::pin::Pin>::new_unchecked(&mut pinned)
}) {
::std::task::Poll::Ready(result) => break result,
::std::task::Poll::Pending => {}
}
yield ();
}
}
```
With this commit, await is lowered as:
```rust
match future {
mut pinned => loop {
match ::std::future::poll_with_tls_context(unsafe {
<::std::pin::Pin>::new_unchecked(&mut pinned)
}) {
::std::task::Poll::Ready(result) => break result,
::std::task::Poll::Pending => {}
}
yield ();
}
}
```
However, this change has the following side-effects:
- All temporaries in future will be considered to live across a
yield for the purpose of auto-traits.
- Borrowed temporaries in future are likely to be considered to be live
across the yield for the purpose of the generator transform.
Signed-off-by: David Wood <david@davidtw.co>
Resolve attributes in several places
Resolve attributes for Arm, Field, FieldPat, GenericParam, Param, StructField and Variant.
This PR is based on @petrochenkov work located at 83fdb8d598.
