user0/rust
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Recognize type Alias = dyn Trait in fn return types

Browse source 
```
error[E0277]: the size for values of type `(dyn Debug + 'static)` cannot be known at compilation time
  --> $DIR/dyn-trait-type-alias-return-type.rs:4:11
   |
LL | fn f() -> T { loop {} }
   |           ^ doesn't have a size known at compile-time
   |
   = help: the trait `Sized` is not implemented for `(dyn Debug + 'static)`
note: this type alias is unsized
  --> $DIR/dyn-trait-type-alias-return-type.rs:1:1
   |
LL | type T = dyn core::fmt::Debug;
   | ^^^^^^
   = note: the return type of a function must have a statically known size
```
This commit is contained in:
Esteban Küber 2025-11-04 18:41:04 +00:00
parent 8cc9c5ebb1
commit 94aa13a09c
1 changed files with 17 additions and 20 deletions
Download patch file Download diff file Expand all files Collapse all files

37
tests/ui/future_not_send.stderr
View file

@ -1,8 +1,8 @@
error: future cannot be sent between threads safely
--> tests/ui/future_not_send.rs:8:1
--> tests/ui/future_not_send.rs:8:62
|
LL | async fn private_future(rc: Rc<[u8]>, cell: &Cell<usize>) -> bool {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ future returned by `private_future` is not `Send`
| ^^^^ future returned by `private_future` is not `Send`
|
note: future is not `Send` as this value is used across an await
--> tests/ui/future_not_send.rs:11:20
@ -23,10 +23,10 @@ LL | async fn private_future(rc: Rc<[u8]>, cell: &Cell<usize>) -> bool {
= help: to override `-D warnings` add `#[allow(clippy::future_not_send)]`
error: future cannot be sent between threads safely
--> tests/ui/future_not_send.rs:14:1
--> tests/ui/future_not_send.rs:14:41
|
LL | pub async fn public_future(rc: Rc<[u8]>) {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ future returned by `public_future` is not `Send`
| ^ future returned by `public_future` is not `Send`
|
note: future is not `Send` as this value is used across an await
--> tests/ui/future_not_send.rs:17:20
@ -39,10 +39,10 @@ LL | async { true }.await;
= note: `std::rc::Rc<[u8]>` doesn't implement `std::marker::Send`
error: future cannot be sent between threads safely
--> tests/ui/future_not_send.rs:24:1
--> tests/ui/future_not_send.rs:24:63
|
LL | async fn private_future2(rc: Rc<[u8]>, cell: &Cell<usize>) -> bool {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ future returned by `private_future2` is not `Send`
| ^^^^ future returned by `private_future2` is not `Send`
|
note: captured value is not `Send`
--> tests/ui/future_not_send.rs:24:26
@ -58,10 +58,10 @@ LL | async fn private_future2(rc: Rc<[u8]>, cell: &Cell<usize>) -> bool {
= note: `std::cell::Cell<usize>` doesn't implement `std::marker::Sync`
error: future cannot be sent between threads safely
--> tests/ui/future_not_send.rs:30:1
--> tests/ui/future_not_send.rs:30:42
|
LL | pub async fn public_future2(rc: Rc<[u8]>) {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ future returned by `public_future2` is not `Send`
| ^ future returned by `public_future2` is not `Send`
|
note: captured value is not `Send`
--> tests/ui/future_not_send.rs:30:29
@ -71,10 +71,10 @@ LL | pub async fn public_future2(rc: Rc<[u8]>) {}
= note: `std::rc::Rc<[u8]>` doesn't implement `std::marker::Send`
error: future cannot be sent between threads safely
--> tests/ui/future_not_send.rs:42:5
--> tests/ui/future_not_send.rs:42:39
|
LL | async fn private_future(&self) -> usize {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ future returned by `private_future` is not `Send`
| ^^^^^ future returned by `private_future` is not `Send`
|
note: future is not `Send` as this value is used across an await
--> tests/ui/future_not_send.rs:45:24
@ -87,10 +87,10 @@ LL | async { true }.await;
= note: `std::rc::Rc<[u8]>` doesn't implement `std::marker::Sync`
error: future cannot be sent between threads safely
--> tests/ui/future_not_send.rs:49:5
--> tests/ui/future_not_send.rs:49:38
|
LL | pub async fn public_future(&self) {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ future returned by `public_future` is not `Send`
| ^ future returned by `public_future` is not `Send`
|
note: captured value is not `Send` because `&` references cannot be sent unless their referent is `Sync`
--> tests/ui/future_not_send.rs:49:32
@ -100,13 +100,10 @@ LL | pub async fn public_future(&self) {
= note: `std::rc::Rc<[u8]>` doesn't implement `std::marker::Sync`
error: future cannot be sent between threads safely
--> tests/ui/future_not_send.rs:61:1
--> tests/ui/future_not_send.rs:61:37
|
LL | / async fn generic_future<T>(t: T) -> T
LL | |
LL | | where
LL | | T: Send,
| |____________^ future returned by `generic_future` is not `Send`
LL | async fn generic_future<T>(t: T) -> T
| ^ future returned by `generic_future` is not `Send`
|
note: future is not `Send` as this value is used across an await
--> tests/ui/future_not_send.rs:67:20
@ -118,10 +115,10 @@ LL | async { true }.await;
= note: `T` doesn't implement `std::marker::Sync`
error: future cannot be sent between threads safely
--> tests/ui/future_not_send.rs:83:1
--> tests/ui/future_not_send.rs:83:51
|
LL | async fn generic_future_always_unsend<T>(_: Rc<T>) {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ future returned by `generic_future_always_unsend` is not `Send`
| ^ future returned by `generic_future_always_unsend` is not `Send`
|
note: future is not `Send` as this value is used across an await
--> tests/ui/future_not_send.rs:86:20