Detect type parameter that might require lifetime constraint.
Do not name `ReVar`s in expected/found output.
Reword text suggesting to check the lifetimes.
add issue 72373 tests
fmt test
fix suggestion format
Replacement, not insertion of suggested string
implement review changes
refactor to span_suggestion_verbose, improve suggestion message, change id @ pattern space formatting
fmt
fix diagnostics spacing between ident and @
refactor reference
Add test for old compiler ICE when using `Borrow`
The original issue was caused by implementing `Borrow` on a local type and using the tokio-reactor crate which had this impl: https://github.com/tokio-rs/tokio/blob/tokio-0.1.4/tokio-reactor/src/poll_evented.rs#L547-L577
This causes an ICE on Rust 1.27.0:
```console
$ RUSTUP_TOOLCHAIN=1.27.0 rustc src/test/ui/issues/issue-50687-ice-on-borrow.rs
error: internal compiler error: librustc/traits/structural_impls.rs:180: impossible case reached
thread 'main' panicked at 'Box<Any>', librustc_errors/lib.rs:554:9
note: Run with `RUST_BACKTRACE=1` for a backtrace.
error: aborting due to previous error
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 1.27.0 (3eda71b00 2018-06-19) running on x86_64-apple-darwin
```
Closes#50687
Warn about unused crate deps
Implements #57274 by adding -Wunused-crate-dependencies. This will warn about any `--extern` option on the command line which isn't referenced by the crate source either via `use` or `extern crate`.
Crates which are added for some side effect but are otherwise unreferenced - such as for symbols they define - the warning can be suppressed with `use somecrate as _;`.
If a crate has multiple aliases (eg using `foo = { package = "bar" }` in `Cargo.toml`), then it will warn about each unused alias.
This does not consider crate added by some other means than `--extern`, including the standard library. It also doesn't consider any crate without `add_prelude` set (though I'm not sure about this).
Unfortunately this probably [does not yet work well with Cargo](https://github.com/rust-lang/rust/issues/57274#issuecomment-624839355) as it will over-specify crates, causing spurious warnings. As a result, this lint is "allow" by default and must be explicitly enabled either via `#![warn(unused_crate_deps)]` or with `-Wunused-crate-deps`.
add a lint against references to packed fields
Creating a reference to an insufficiently aligned packed field is UB and should be disallowed, both inside and outside of `unsafe` blocks. However, currently there is no stable alternative (https://github.com/rust-lang/rust/issues/64490) so all we do right now is have a future incompatibility warning when doing this outside `unsafe` (https://github.com/rust-lang/rust/issues/46043).
This adds an allow-by-default lint. @retep998 suggested this can help early adopters avoid issues. It also means we can then do a crater run where this is deny-by-default as suggested by @joshtriplett.
I guess the main thing to bikeshed is the lint name. I am not particularly happy with "packed_references" as it sounds like the packed field has reference type. I chose this because it is similar to "safe_packed_borrows". What about "reference_to_packed" or "unaligned_reference" or so?
Fixes#72590
With PR #70551, observing a `ty::Error` guarantees that compilation is
going to fail. Therefore, there are no soundness impliciations to
continuing on when we encounter a `ty::Error` - we can only affect
whether or not additional error messags are emitted.
By not bailing out, we avoid incorrectly determining that types are
`!Sized` when a type error is present, which allows us to avoid emitting
additional spurious error messages.
The original comment mentioned this code being shared by coherence -
howver, this change resulted in no diagnostic changes in any of the
existing tests.
The previous code paniced if offset_bytes == i64::MIN. This commit:
- Properly computes the absoulte value to avoid this panic
- Adds a test for this edge case
Signed-off-by: Joe Richey <joerichey@google.com>
Fixes#68104
Previous, we were encoding AnonConst as a regular Const, causing us to
treat them differently after being deserialized in another compilation
session.
This will print a diagnostic for crates which are mentioned as `--extern`
arguments on the command line, but are never referenced from the source.
This diagnostic is controlled by `-Wunused-crate-dependencies` or
`#![warn(unused_crate_dependencies)]` and is "allow" by default.
There are cases where certain crates need to be linked in but are not
directly referenced - for example if they are providing symbols for C
linkage. In this case the warning can be suppressed with
`use needed_crate as _;`.
Thanks to @petrochenkov for simplified core.
Resolves issue #57274
Fixes#69446
When we encounter a region error involving an `FnMut` closure, we
display a specialized error message. However, we currently do not
tell the user which upvar was captured. This makes it difficult to
determine the cause of the error, especially when the closure is large.
This commit records marks constraints involving closure upvars
with `ConstraintCategory::ClosureUpvar`. When we decide to 'blame'
a `ConstraintCategory::Return`, we additionall store
the captured upvar if we found a `ConstraintCategory::ClosureUpvar` in
the path.
When generating an error message, we point to relevant spans if we have
closure upvar information available. We further customize the message if
an `async` closure is being returned, to make it clear that the captured
variable is being returned indirectly.
Fix bug in shebang handling
Shebang handling was too agressive in stripping out the first line in cases where it is actually _not_ a shebang, but instead, valid rust (#70528). This is a second attempt at resolving this issue (the first attempt was reverted, for, among other reasons, causing an ICE in certain cases (#71372, #71471).
The behavior is now codified by a number of UI tests, but simply:
For the first line to be a shebang, the following must all be true:
1. The line must start with `#!`
2. The line must contain a non-whitespace character after `#!`
3. The next character in the file, ignoring comments & whitespace must not be `[`
I believe this is a strict superset of what we used to allow, so perhaps a crater run is unnecessary, but probably not a terrible idea.
Fixes#70528
add regression tests for stalled_on const vars
closes#70180
Afaict this has been fixed sometime after #70213
`trait_ref_type_vars` correctly adds const infers and I did not find any remaining `FIXME`s which correspond to this issue.
7c59a81a5f/src/librustc_trait_selection/traits/fulfill.rs (L555-L557)
Added both examples from the issue as regression tests and renamed `trait_ref_type_vars` -> `trait_ref_infer_vars`.
r? @eddyb
Rollup of 4 pull requests
Successful merges:
- #72153 (exhaustively check `ty::Kind` during structural match checking)
- #72308 (Emit a better diagnostic when function actually has a 'self' parameter)
- #72560 (Enable `glacier` command via triagebot)
- #72567 (Clean up E0608 explanation)
Failed merges:
r? @ghost
Emit a better diagnostic when function actually has a 'self' parameter
Fixes#66898
When we are unable to resolve a reference to `self`, we current assume
that the containing function doesn't have a `self` parameter, and
emit an error message accordingly.
However, if the reference to `self` was created by a macro invocation,
then resolution will correctly fail, due to hygiene. In this case, we
don't want to tell the user that the containing fuction doesn't have a
'self' paramter if it actually has one.
This PR checks for the precense of a 'self' parameter, and adjusts the
error message we emit accordingly.
TODO: The exact error message we emit could probably be improved. Should
we explicitly mention hygiene?
exhaustively check `ty::Kind` during structural match checking
This was prone to errors as we may forget new kinds in the future.
I am also not yet sure about some kinds.
`ty::GeneratorWitness(..) | ty::Infer(_) | ty::Placeholder(_) | ty::UnnormalizedProjection(..) | ty::Bound(..)` might be unreachable here.
We may want to forbid `ty::Projection`, similar to `ty::Param`.
`ty::Opaque` seems fine afaict, should not be possible in a match atm.
I believe `ty::Foreign` should not be structurally match, as I don't even know what
that would actually mean.
r? @pnkfelix cc @eddyb
Shebang handling was too agressive in stripping out the first line in cases where it is actually _not_ a shebang, but instead, valid rust (#70528). This is a second attempt at resolving this issue (the first attempt was flawed, for, among other reasons, causing an ICE in certain cases (#71372, #71471).
The behavior is now codified by a number of UI tests, but simply:
For the first line to be a shebang, the following must all be true:
1. The line must start with `#!`
2. The line must contain a non whitespace character after `#!`
3. The next character in the file, ignoring comments & whitespace must not be `[`
I believe this is a strict superset of what we used to allow, so perhaps a crater run is unnecessary, but probably not a terrible idea.
