rustc_lexer: Optimize shebang detection slightly
Sorry, I just couldn't resist.
It shouldn't make any difference in practice.
Also, documented a previously unnoticed case with doc comments treated as regular comments during shebang detection.
Fix missing parentheses Fn notation error
Fixes #72611
Well, fixes the error output, I think E0658 is the right error to throw in this case so I didn't change that
Add -Z profile-emit=<path> for Gcov gcda output.
Adds a -Z flag to control the file path that the Gcov gcda output is
written to during runtime. This flag expects a path and filename, e.g.
-Z profile-emit=gcov/out/lib.gcda.
This works similar to GCC/Clang's -fprofile-dir flag which allows
control over the output path for gcda coverage files.
Allow types (with lifetimes/generics) in impl_lint_pass
cc https://github.com/rust-lang/rust-clippy/pull/5279#discussion_r430790267
This allows to implement `LintPass` for types with lifetimes and/or generics. The only thing, I'm not sure of is the `LintPass::name` function, which now includes the lifetime(s) (which will be `'_` most of the time) in the name returned for the lint pass, if it exists. But I don't think that this should be a problem, since the `LintPass::name` is never used for output for the user (?).
Improve inline asm error diagnostics
Previously we were just using the raw LLVM error output (with line, caret, etc) as the diagnostic message, which ends up looking rather out of place with our existing diagnostics.
The new diagnostics properly format the diagnostics and also take advantage of LLVM's per-line `srcloc` attribute to map an error in inline assembly directly to the relevant line of source code.
Incidentally also fixes#71639 by disabling `srcloc` metadata during LTO builds since we don't know what crate it might have come from. We can only resolve `srcloc`s from the currently crate since it indexes into the source map for the current crate.
Fixes#72664Fixes#71639
r? @petrochenkov
### Old style
```rust
#![feature(llvm_asm)]
fn main() {
unsafe {
let _x: i32;
llvm_asm!(
"mov $0, $1
invalid_instruction $0, $1
mov $0, $1"
: "=&r" (_x)
: "r" (0)
:: "intel"
);
}
}
```
```
error: <inline asm>:3:14: error: invalid instruction mnemonic 'invalid_instruction'
invalid_instruction ecx, eax
^~~~~~~~~~~~~~~~~~~
--> src/main.rs:6:9
|
6 | / llvm_asm!(
7 | | "mov $0, $1
8 | | invalid_instruction $0, $1
9 | | mov $0, $1"
... |
12 | | :: "intel"
13 | | );
| |__________^
```
### New style
```rust
#![feature(asm)]
fn main() {
unsafe {
asm!(
"mov {0}, {1}
invalid_instruction {0}, {1}
mov {0}, {1}",
out(reg) _,
in(reg) 0i64,
);
}
}
```
```
error: invalid instruction mnemonic 'invalid_instruction'
--> test.rs:7:14
|
7 | invalid_instruction {0}, {1}
| ^
|
note: instantiated into assembly here
--> <inline asm>:3:14
|
3 | invalid_instruction rax, rcx
| ^^^^^^^^^^^^^^^^^^^
```
Account for missing lifetime in opaque and trait object return types
When encountering an opaque closure return type that needs to bound a
lifetime to the function's arguments, including borrows and type params,
provide appropriate suggestions that lead to working code.
Get the user from
```rust
fn foo<G, T>(g: G, dest: &mut T) -> impl FnOnce()
where
G: Get<T>
{
move || {
*dest = g.get();
}
}
```
to
```rust
fn foo<'a, G: 'a, T>(g: G, dest: &'a mut T) -> impl FnOnce() +'a
where
G: Get<T>
{
move || {
*dest = g.get();
}
}
```
When encountering an opaque closure return type that needs to bound a
lifetime to the function's arguments, including borrows and type params,
provide appropriate suggestions that lead to working code.
Get the user from
```rust
fn foo<G, T>(g: G, dest: &mut T) -> impl FnOnce()
where
G: Get<T>
{
move || {
*dest = g.get();
}
}
```
to
```rust
fn foo<'a, G: 'a, T>(g: G, dest: &'a mut T) -> impl FnOnce() +'a
where
G: Get<T>
{
move || {
*dest = g.get();
}
}
```
multiple Return terminators are possible
@ecstatic-morse mentioned in https://github.com/rust-lang/rust/issues/72515 that multiple `Return` terminators are possible. Update the docs accordingly.
Cc @rust-lang/wg-mir-opt
mir: adjust conditional in recursion limit check
Fixes#67552.
This PR adjusts the condition used in the recursion limit check of
the monomorphization collector, from `>` to `>=`.
In #67552, the test case had infinite indirect recursion, repeating a
handful of functions (from the perspective of the monomorphization
collector): `rec` -> `identity` -> `Iterator::count` -> `Iterator::fold`
-> `Iterator::next` -> `rec`.
During this process, `resolve_associated_item` was invoked for
`Iterator::fold` (during the construction of an `Instance`), and
ICE'd due to substitutions needing inference. However, previous
iterations of this recursion would have called this function for
`Iterator::fold` - and did! - and succeeded in doing so (trivially
checkable from debug logging, `()` is present where `_` is in the substs
of the failing execution).
The expected outcome of this test case would be a recursion limit error
(which is present when the `identity` fn indirection is removed), and
the recursion depth of `rec` is increasing (other functions finish
collecting their neighbours and thus have their recursion depths reset).
When the ICE occurs, the recursion depth of `rec` is 256 (which matches
the recursion limit), which suggests perhaps that a different part of
the compiler is using a `>=` comparison and returning a different result
on this recursion rather than what it returned in every previous
recursion, thus stopping the monomorphization collector from reporting
an error on the next recursion, where `recursion_depth_of_rec > 256`
would have been true.
With grep and some educated guesses, we can determine that
the recursion limit check at line 818 in
`src/librustc_trait_selection/traits/project.rs` is the other check that
is using a different comparison. Modifying either comparison to be `>` or
`>=` respectively will fix the error, but changing the monomorphization
collector produces the nicer error.
Override Box::<[T]>::clone_from
Avoid dropping and reallocating when cloning to an existing box if the lengths are the same.
It would be nice if this could also be specialized for `Copy` but I don't know how that works since it's not on stable. Will gladly look into it if it's deemed as a good idea.
This is my first PR with code, hope I did everything right 😄
Fix ICE with explicit late-bound lifetimes
Rather than returning an explicit late-bound lifetime as a generic argument count mismatch (which is not necessarily true), this PR propagates the presence of explicit late-bound lifetimes.
This avoids an ICE that can occur due to the presence of explicit late-bound lifetimes when building generic substitutions by explicitly ignoring them.
r? @varkor
cc @davidtwco (this removes a check you introduced in #60892)
Resolves#72278
Resolve overflow behavior for RangeFrom
This specifies a documented unspecified implementation detail of `RangeFrom` and makes it consistently implement the specified behavior.
Specifically, `(u8::MAX).next()` is defined to cause an overflow, and resolve that overflow in the same manner as the `Step::forward` implementation.
The inconsistency that has existed is `<RangeFrom as Iterator>::nth`. The existing behavior should be plain to see after #69659: the skipping part previously always panicked if it caused an overflow, but the final step (to set up the state for further iteration) has always been debug-checked.
The inconsistency, then, is that `RangeFrom::nth` does not implement the same behavior as the naive (and default) implementation of just calling `next` multiple times. This PR aligns `RangeFrom::nth` to have identical behavior to the naive implementation. It also lines up with the standard behavior of primitive math in Rust everywhere else in the language: debug checked overflow.
cc @Amanieu
---
Followup to #69659. Closes#25708 (by documenting the panic as intended).
The documentation wording is preliminary and can probably be improved.
This will probably need an FCP, as it changes observable stable behavior.
Rollup of 10 pull requests
Successful merges:
- #72033 (Update RELEASES.md for 1.44.0)
- #72162 (Add Extend::{extend_one,extend_reserve})
- #72419 (Miri read_discriminant: return a scalar instead of raw underlying bytes)
- #72621 (Don't bail out of trait selection when predicate references an error)
- #72677 (Fix diagnostics for `@ ..` binding pattern in tuples and tuple structs)
- #72710 (Add test to make sure -Wunused-crate-dependencies works with tests)
- #72724 (Revert recursive `TokenKind::Interpolated` expansion for now)
- #72741 (Remove unused mut from long-linker-command-lines test)
- #72750 (Remove remaining calls to `as_local_node_id`)
- #72752 (remove mk_bool)
Failed merges:
r? @ghost
Such splits arise from metadata refs into libstd.
This way, we can (in a follow on commit) continue to emit the virtual name into
things like the like the StableSourceFileId that ends up in incremetnal build
artifacts, while still using the devirtualized file path when we want to access
the file.
Note that this commit is intended to be a refactoring; the actual fix to the bug
in question is in a follow-on commit.
