Improve the "try using a variant of the expected type" hint.
Fix https://github.com/rust-lang/rust/issues/65494.
- Change type-printing output.
- Use `span_to_snippet` when possible.
- Change the message to `try using a variant of the expected enum`
Point at the span for the definition of ADTs internal to the current
crate.
Look at the leading char of the ident to determine whether we're
expecting a likely fn or any of a fn, a tuple struct or a tuple variant.
Turn fn `add_typo_suggestion` into a `Resolver` method.
Reword E0392 slightly
Make it clearer that a type or lifetime argument not being used can be
fixed by referencing it in a struct's fields, not just using `PhathomData`.
CC #53589.
Remove redundancy from the implementation of C variadics.
This cleanup was first described in https://github.com/rust-lang/rust/issues/44930#issuecomment-497163539:
* AST doesn't track `c_variadic: bool` anymore, relying solely on a trailing `CVarArgs` type in fn signatures
* HIR doesn't have a `CVarArgs` anymore, relying solely on `c_variadic: bool`
* same for `ty::FnSig` (see tests for diagnostics improvements from that)
* `{hir,mir}::Body` have one extra argument than the signature when `c_variadic == true`
* `rustc_typeck` and `rustc_mir::{build,borrowck}` need to give that argument the right type (which no longer uses a lifetime parameter, but a function-internal scope)
* `rustc_target::abi::call` doesn't need special hacks anymore (since it never sees the `VaListImpl` now, it's all inside the body)
r? @nagisa / @rkruppe cc @dlrobertson @oli-obk
Where possible, the error message includes the name of the crate
that brought in the crate with duplicate lang items (which
helps with debugging). This information is passed on from cstore
using the `extern_crate` query.
Remove blanket silencing of "type annotation needed" errors
Remove blanket check for existence of other errors before emitting "type annotation needed" errors, and add some eager checks to avoid adding obligations when they refer to types that reference `[type error]` in order to reduce unneeded errors.
Fix#64084.
Remove blanket check for existence of other errors before emitting
"type annotation needed" errors, and add some eager checks to avoid
adding obligations when they refer to types that reference
`[type error]` in order to reduce unneded errors.
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.
