rust/tests/ui/delegation/unsupported.stderr

error[E0391]: cycle detected when computing type of `opaque::<impl at $DIR/unsupported.rs:25:5: 25:24>::{synthetic#0}`
  --> $DIR/unsupported.rs:26:25
   |
LL |         reuse to_reuse::opaque_ret;
   |                         ^^^^^^^^^^
   |
note: ...which requires comparing an impl and trait method signature, inferring any hidden `impl Trait` types in the process...
  --> $DIR/unsupported.rs:26:25
   |
LL |         reuse to_reuse::opaque_ret;
   |                         ^^^^^^^^^^
   = note: ...which again requires computing type of `opaque::<impl at $DIR/unsupported.rs:25:5: 25:24>::{synthetic#0}`, completing the cycle
note: cycle used when checking that `opaque::<impl at $DIR/unsupported.rs:25:5: 25:24>` is well-formed
  --> $DIR/unsupported.rs:25:5
   |
LL |     impl ToReuse for u8 {
   |     ^^^^^^^^^^^^^^^^^^^
   = note: see https://rustc-dev-guide.rust-lang.org/overview.html#queries and https://rustc-dev-guide.rust-lang.org/query.html for more information

warning: this function depends on never type fallback being `()`
  --> $DIR/unsupported.rs:13:9
   |
LL |         pub fn opaque_ret() -> impl Trait { unimplemented!() }
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
   = note: for more information, see issue #123748 <https://github.com/rust-lang/rust/issues/123748>
   = help: specify the types explicitly
note: in edition 2024, the requirement `!: opaque::Trait` will fail
  --> $DIR/unsupported.rs:13:32
   |
LL |         pub fn opaque_ret() -> impl Trait { unimplemented!() }
   |                                ^^^^^^^^^^
   = note: `#[warn(dependency_on_unit_never_type_fallback)]` on by default

warning: this function depends on never type fallback being `()`
  --> $DIR/unsupported.rs:19:9
   |
LL |         fn opaque_ret() -> impl Trait { unimplemented!() }
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
   = note: for more information, see issue #123748 <https://github.com/rust-lang/rust/issues/123748>
   = help: specify the types explicitly
note: in edition 2024, the requirement `!: opaque::Trait` will fail
  --> $DIR/unsupported.rs:19:28
   |
LL |         fn opaque_ret() -> impl Trait { unimplemented!() }
   |                            ^^^^^^^^^^

error[E0391]: cycle detected when computing type of `opaque::<impl at $DIR/unsupported.rs:28:5: 28:25>::{synthetic#0}`
  --> $DIR/unsupported.rs:29:24
   |
LL |         reuse ToReuse::opaque_ret;
   |                        ^^^^^^^^^^
   |
note: ...which requires comparing an impl and trait method signature, inferring any hidden `impl Trait` types in the process...
  --> $DIR/unsupported.rs:29:24
   |
LL |         reuse ToReuse::opaque_ret;
   |                        ^^^^^^^^^^
   = note: ...which again requires computing type of `opaque::<impl at $DIR/unsupported.rs:28:5: 28:25>::{synthetic#0}`, completing the cycle
note: cycle used when checking that `opaque::<impl at $DIR/unsupported.rs:28:5: 28:25>` is well-formed
  --> $DIR/unsupported.rs:28:5
   |
LL |     impl ToReuse for u16 {
   |     ^^^^^^^^^^^^^^^^^^^^
   = note: see https://rustc-dev-guide.rust-lang.org/overview.html#queries and https://rustc-dev-guide.rust-lang.org/query.html for more information

error: recursive delegation is not supported yet
  --> $DIR/unsupported.rs:42:22
   |
LL |         pub reuse to_reuse2::foo;
   |                              --- callee defined here
...
LL |     reuse to_reuse1::foo;
   |                      ^^^

error[E0283]: type annotations needed
  --> $DIR/unsupported.rs:52:18
   |
LL |     reuse Trait::foo;
   |                  ^^^ cannot infer type
   |
   = note: cannot satisfy `_: effects::Trait`

error: aborting due to 4 previous errors; 2 warnings emitted

Some errors have detailed explanations: E0283, E0391.
For more information about an error, try `rustc --explain E0283`.