src/test/ui/generic-associated-types/issue-76535.stderr

   1 warning: the feature `generic_associated_types` is incomplete and may not be safe to use and/or cause compiler crashes
   2   --> $DIR/issue-76535.rs:1:12
   3    |
   4 LL | #![feature(generic_associated_types)]
   5    |            ^^^^^^^^^^^^^^^^^^^^^^^^
   6    |
   7    = note: `#[warn(incomplete_features)]` on by default
   8    = note: see issue #44265 <https://github.com/rust-lang/rust/issues/44265> for more information
   9
  10 error[E0107]: missing generics for associated type `SuperTrait::SubType`
  11   --> $DIR/issue-76535.rs:7:10
  12    |
  13 LL |     type SubType<'a>: SubTrait;
  14    |          ^^^^^^^ expected 1 lifetime argument
  15    |
  16 note: associated type defined here, with 1 lifetime parameter: `'a`
  17   --> $DIR/issue-76535.rs:7:10
  18    |
  19 LL |     type SubType<'a>: SubTrait;
  20    |          ^^^^^^^ --
  21 help: use angle brackets to add missing lifetime argument
  22    |
  23 LL |     type SubType<'a><'a>: SubTrait;
  24    |                 ^^^^
  25
  26 error[E0038]: the trait `SuperTrait` cannot be made into an object
  27   --> $DIR/issue-76535.rs:38:14
  28    |
  29 LL |     let sub: Box<dyn SuperTrait<SubType = SubStruct>> = Box::new(SuperStruct::new(0));
  30    |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `SuperTrait` cannot be made into an object
  31    |
  32    = help: consider moving `SubType` to another trait
  33 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>
  34   --> $DIR/issue-76535.rs:7:10
  35    |
  36 LL | pub trait SuperTrait {
  37    |           ---------- this trait cannot be made into an object...
  38 LL |     type SubType<'a>: SubTrait;
  39    |          ^^^^^^^ ...because it contains the generic associated type `SubType`
  40
  41 error[E0038]: the trait `SuperTrait` cannot be made into an object
  42   --> $DIR/issue-76535.rs:38:57
  43    |
  44 LL |     let sub: Box<dyn SuperTrait<SubType = SubStruct>> = Box::new(SuperStruct::new(0));
  45    |                                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `SuperTrait` cannot be made into an object
  46    |
  47    = help: consider moving `SubType` to another trait
  48 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>
  49   --> $DIR/issue-76535.rs:7:10
  50    |
  51 LL | pub trait SuperTrait {
  52    |           ---------- this trait cannot be made into an object...
  53 LL |     type SubType<'a>: SubTrait;
  54    |          ^^^^^^^ ...because it contains the generic associated type `SubType`
  55    = note: required because of the requirements on the impl of `CoerceUnsized<Box<dyn SuperTrait<SubType = SubStruct<'_>>>>` for `Box<SuperStruct>`
  56    = note: required by cast to type `Box<dyn SuperTrait<SubType = SubStruct<'_>>>`
  57
  58 error: aborting due to 3 previous errors; 1 warning emitted
  59
  60 Some errors have detailed explanations: E0038, E0107.
  61 For more information about an error, try `rustc --explain E0038`.