rust/tests/ui/wf/wf-fn-where-clause.stderr

error[E0277]: the trait bound `U: Copy` is not satisfied
  --> $DIR/wf-fn-where-clause.rs:8:24
   |
LL | fn foo<T,U>() where T: ExtraCopy<U>
   |                        ^^^^^^^^^^^^ the trait `Copy` is not implemented for `U`
   |
note: required by a bound in `ExtraCopy`
  --> $DIR/wf-fn-where-clause.rs:6:19
   |
LL | trait ExtraCopy<T:Copy> { }
   |                   ^^^^ required by this bound in `ExtraCopy`
help: consider further restricting type parameter `U`
   |
LL | fn foo<T,U>() where T: ExtraCopy<U>, U: std::marker::Copy
   |                                    ++++++++++++++++++++++

error[E0038]: the trait `Copy` cannot be made into an object
  --> $DIR/wf-fn-where-clause.rs:12:16
   |
LL | fn bar() where Vec<dyn Copy>:, {}
   |                ^^^^^^^^^^^^^ `Copy` cannot be made into an object
   |
   = note: the trait cannot be made into an object because it requires `Self: Sized`
   = note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>

error[E0277]: the size for values of type `(dyn Copy + 'static)` cannot be known at compilation time
  --> $DIR/wf-fn-where-clause.rs:12:16
   |
LL | fn bar() where Vec<dyn Copy>:, {}
   |                ^^^^^^^^^^^^^ doesn't have a size known at compile-time
   |
   = help: the trait `Sized` is not implemented for `(dyn Copy + 'static)`
note: required by an implicit `Sized` bound in `Vec`
  --> $DIR/wf-fn-where-clause.rs:16:12
   |
LL | struct Vec<T> {
   |            ^ required by the implicit `Sized` requirement on this type parameter in `Vec`
help: you could relax the implicit `Sized` bound on `T` if it were used through indirection like `&T` or `Box<T>`
  --> $DIR/wf-fn-where-clause.rs:16:12
   |
LL | struct Vec<T> {
   |            ^ this could be changed to `T: ?Sized`...
LL |     t: T,
   |        - ...if indirection were used here: `Box<T>`

error: aborting due to 3 previous errors

Some errors have detailed explanations: E0038, E0277.
For more information about an error, try `rustc --explain E0038`.
pretty: trim paths of unique symbols If a symbol name can only be imported from one place for a type, and as long as it was not glob-imported anywhere in the current crate, we can trim its printed path and print only the name. This has wide implications on error messages with types, for example, shortening `std::vec::Vec` to just `Vec`, as long as there is no other `Vec` importable anywhere. This adds a new '-Z trim-diagnostic-paths=false' option to control this feature. On the good path, with no diagnosis printed, we should try to avoid issuing this query, so we need to prevent trimmed_def_paths query on several cases. This change also relies on a previous commit that differentiates between `Debug` and `Display` on various rustc types, where the latter is trimmed and presented to the user and the former is not. 2020-09-02 07:40:56 +00:00			error[E0277]: the trait bound `U: Copy` is not satisfied
Use more accurate failed predicate spans 2020-01-30 00:55:37 +00:00			`--> $DIR/wf-fn-where-clause.rs:8:24`
Moved compile-fail tests to ui tests. 2018-08-08 12:28:26 +00:00			`\|`
Point at arguments or output when fn obligations come from them, or ident when they don't 2020-01-18 22:57:56 +00:00			`LL \| fn foo<T,U>() where T: ExtraCopy<U>`
pretty: trim paths of unique symbols If a symbol name can only be imported from one place for a type, and as long as it was not glob-imported anywhere in the current crate, we can trim its printed path and print only the name. This has wide implications on error messages with types, for example, shortening `std::vec::Vec` to just `Vec`, as long as there is no other `Vec` importable anywhere. This adds a new '-Z trim-diagnostic-paths=false' option to control this feature. On the good path, with no diagnosis printed, we should try to avoid issuing this query, so we need to prevent trimmed_def_paths query on several cases. This change also relies on a previous commit that differentiates between `Debug` and `Display` on various rustc types, where the latter is trimmed and presented to the user and the former is not. 2020-09-02 07:40:56 +00:00			\| ^^^^^^^^^^^^ the trait `Copy` is not implemented for `U`
Improve reporting errors and suggestions for trait bounds 2019-12-26 12:43:33 +00:00			`\|`
Use note to point at bound introducing requirement 2021-07-31 16:26:55 +00:00			note: required by a bound in `ExtraCopy`
			`--> $DIR/wf-fn-where-clause.rs:6:19`
			`\|`
			`LL \| trait ExtraCopy<T:Copy> { }`
			\| ^^^^ required by this bound in `ExtraCopy`
Tweak `suggest_constraining_type_param` Some of the bound restriction structured suggestions were incorrect while others had subpar output. 2020-03-14 02:28:14 +00:00			help: consider further restricting type parameter `U`
Improve reporting errors and suggestions for trait bounds 2019-12-26 12:43:33 +00:00			`\|`
give full path of constraint in suggest_constraining_type_param revert file bless with nll mode 2021-03-30 09:56:39 +00:00			`LL \| fn foo<T,U>() where T: ExtraCopy<U>, U: std::marker::Copy`
Modify structured suggestion output * On suggestions that include deletions, use a diff inspired output format * When suggesting addition, use `+` as underline * Color highlight modified span 2021-06-22 02:07:19 +00:00			`\| ++++++++++++++++++++++`
Moved compile-fail tests to ui tests. 2018-08-08 12:28:26 +00:00
Reorder fullfillment errors to keep more interesting ones first In `report_fullfillment_errors` push back `T: Sized`, `T: WellFormed` and coercion errors to the end of the list. The pre-existing deduplication logic eliminates redundant errors better that way, keeping the resulting output with fewer errors than before, while also having more detail. 2023-08-14 13:09:53 +00:00			error[E0038]: the trait `Copy` cannot be made into an object
			`--> $DIR/wf-fn-where-clause.rs:12:16`
			`\|`
			`LL \| fn bar() where Vec<dyn Copy>:, {}`
			\| ^^^^^^^^^^^^^ `Copy` cannot be made into an object
			`\|`
			= note: the trait cannot be made into an object because it requires `Self: Sized`
			`= note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>`

pretty: trim paths of unique symbols If a symbol name can only be imported from one place for a type, and as long as it was not glob-imported anywhere in the current crate, we can trim its printed path and print only the name. This has wide implications on error messages with types, for example, shortening `std::vec::Vec` to just `Vec`, as long as there is no other `Vec` importable anywhere. This adds a new '-Z trim-diagnostic-paths=false' option to control this feature. On the good path, with no diagnosis printed, we should try to avoid issuing this query, so we need to prevent trimmed_def_paths query on several cases. This change also relies on a previous commit that differentiates between `Debug` and `Display` on various rustc types, where the latter is trimmed and presented to the user and the former is not. 2020-09-02 07:40:56 +00:00			error[E0277]: the size for values of type `(dyn Copy + 'static)` cannot be known at compilation time
Use more accurate failed predicate spans 2020-01-30 00:55:37 +00:00			`--> $DIR/wf-fn-where-clause.rs:12:16`
rustc_typeck: turn `where Type:,` into a WF(Type) predicate, instead of ignoring it. 2018-08-25 21:28:23 +00:00			`\|`
			`LL \| fn bar() where Vec<dyn Copy>:, {}`
Use more accurate failed predicate spans 2020-01-30 00:55:37 +00:00			`\| ^^^^^^^^^^^^^ doesn't have a size known at compile-time`
rustc_typeck: turn `where Type:,` into a WF(Type) predicate, instead of ignoring it. 2018-08-25 21:28:23 +00:00			`\|`
pretty: trim paths of unique symbols If a symbol name can only be imported from one place for a type, and as long as it was not glob-imported anywhere in the current crate, we can trim its printed path and print only the name. This has wide implications on error messages with types, for example, shortening `std::vec::Vec` to just `Vec`, as long as there is no other `Vec` importable anywhere. This adds a new '-Z trim-diagnostic-paths=false' option to control this feature. On the good path, with no diagnosis printed, we should try to avoid issuing this query, so we need to prevent trimmed_def_paths query on several cases. This change also relies on a previous commit that differentiates between `Debug` and `Display` on various rustc types, where the latter is trimmed and presented to the user and the former is not. 2020-09-02 07:40:56 +00:00			= help: the trait `Sized` is not implemented for `(dyn Copy + 'static)`
On E0277 be clearer about implicit `Sized` bounds on type params and assoc types ``` error[E0277]: the size for values of type `[i32]` cannot be known at compilation time --> f100.rs:2:33 \| 2 \| let _ = std::mem::size_of::<[i32]>(); \| ^^^^^ doesn't have a size known at compile-time \| = help: the trait `Sized` is not implemented for `[i32]` note: required by an implicit `Sized` bound in `std::mem::size_of` --> /home/gh-estebank/rust/library/core/src/mem/mod.rs:312:22 \| 312 \| pub const fn size_of<T>() -> usize { \| ^ required by the implicit `Sized` requirement on this bound in `size_of` ``` Fix #120178. 2024-01-24 21:29:15 +00:00			note: required by an implicit `Sized` bound in `Vec`
Use note to point at bound introducing requirement 2021-07-31 16:26:55 +00:00			`--> $DIR/wf-fn-where-clause.rs:16:12`
			`\|`
			`LL \| struct Vec<T> {`
review comment: change wording 2024-01-30 19:47:45 +00:00			\| ^ required by the implicit `Sized` requirement on this type parameter in `Vec`
Provide `help` when `T: ?Sized` can't be suggested 2020-06-17 00:24:16 +00:00			help: you could relax the implicit `Sized` bound on `T` if it were used through indirection like `&T` or `Box<T>`
			`--> $DIR/wf-fn-where-clause.rs:16:12`
			`\|`
			`LL \| struct Vec<T> {`
			\| ^ this could be changed to `T: ?Sized`...
			`LL \| t: T,`
Miscellaneous small diagnostics cleanup 2021-02-04 05:41:18 +00:00			\| - ...if indirection were used here: `Box<T>`
rustc_typeck: turn `where Type:,` into a WF(Type) predicate, instead of ignoring it. 2018-08-25 21:28:23 +00:00
			`error: aborting due to 3 previous errors`
Moved compile-fail tests to ui tests. 2018-08-08 12:28:26 +00:00
hide `--explain` hint if error has no extended info 2019-04-17 17:26:38 +00:00			`Some errors have detailed explanations: E0038, E0277.`
rustc_typeck: turn `where Type:,` into a WF(Type) predicate, instead of ignoring it. 2018-08-25 21:28:23 +00:00			For more information about an error, try `rustc --explain E0038`.