rust/tests/ui/nll/where_clauses_in_structs.stderr

error: lifetime may not live long enough
  --> $DIR/where_clauses_in_structs.rs:11:11
   |
LL | fn bar<'a, 'b>(x: Cell<&'a u32>, y: Cell<&'b u32>) {
   |        --  -- lifetime `'b` defined here
   |        |
   |        lifetime `'a` defined here
LL |     Foo { x, y };
   |           ^ this usage requires that `'a` must outlive `'b`
   |
   = help: consider adding the following bound: `'a: 'b`
   = note: requirement occurs because of the type `Cell<&u32>`, which makes the generic argument `&u32` invariant
   = note: the struct `Cell<T>` is invariant over the parameter `T`
   = help: see <https://doc.rust-lang.org/nomicon/subtyping.html> for more information about variance

error: aborting due to previous error
Update tests 2018-12-11 15:49:40 -06:00			`error: lifetime may not live long enough`
Fully stabilize NLL 2022-04-01 12:13:25 -05:00			`--> $DIR/where_clauses_in_structs.rs:11:11`
Moved compile-fail tests to ui tests. 2018-08-08 07:28:26 -05:00			`\|`
			`LL \| fn bar<'a, 'b>(x: Cell<&'a u32>, y: Cell<&'b u32>) {`
			\| -- -- lifetime `'b` defined here
			`\| \|`
			\| lifetime `'a` defined here
			`LL \| Foo { x, y };`
Add `ConstraintCategory::Usage` for handling aggregate construction In some cases, we emit borrowcheck diagnostics pointing at a particular field expression in a struct expression (e.g. `MyStruct { field: my_expr }`). However, this behavior currently relies on us choosing the `ConstraintCategory::Boring` with the 'correct' span. When adding additional variants to `ConstraintCategory`, (or changing existing usages away from `ConstraintCategory::Boring`), the current behavior can easily get broken, since a non-boring constraint will get chosen over a boring one. To make the diagnostic output less fragile, this commit adds a `ConstraintCategory::Usage` variant. We use this variant for the temporary assignments created for each field of an aggregate we are constructing. Using this new variant, we can emit a message mentioning "this usage", emphasizing the fact that the error message is related to the specific use site (in the struct expression). This is preparation for additional work on improving NLL error messages (see #57374) 2021-09-06 16:59:24 -05:00			\| ^ this usage requires that `'a` must outlive `'b`
implement outlive suggestions 2018-11-28 15:05:36 -06:00			`\|`
update tests 2019-10-27 09:39:14 -05:00			= help: consider adding the following bound: `'a: 'b`
Format invariance notes with backticks 2022-04-02 17:32:39 -05:00			= note: requirement occurs because of the type `Cell<&u32>`, which makes the generic argument `&u32` invariant
			= note: the struct `Cell<T>` is invariant over the parameter `T`
Refactor variance diagnostics to work with more types Instead of special-casing mutable pointers/references, we now support general generic types (currently, we handle `ty::Ref`, `ty::RawPtr`, and `ty::Adt`) When a `ty::Adt` is involved, we show an additional note explaining which of the type's generic parameters is invariant (e.g. the `T` in `Cell<T>`). Currently, we don't explain why a particular generic parameter ends up becoming invariant. In the general case, this could require printing a long 'backtrace' of types, so doing this would be more suitable for a follow-up PR. We still only handle the case where our variance switches to `ty::Invariant`. 2021-09-27 20:22:44 -05:00			`= help: see <https://doc.rust-lang.org/nomicon/subtyping.html> for more information about variance`
implement outlive suggestions 2018-11-28 15:05:36 -06:00
Moved compile-fail tests to ui tests. 2018-08-08 07:28:26 -05:00			`error: aborting due to previous error`