tests/ui/invalid_dispatch_from_dyn_impls.rs

   1 #![feature(unsize, dispatch_from_dyn)]
   2
   3 use std::{
   4     ops::DispatchFromDyn,
   5     marker::{Unsize, PhantomData},
   6 };
   7
   8 struct WrapperWithExtraField<T>(T, i32);
   9
  10 impl<T, U> DispatchFromDyn<WrapperWithExtraField<U>> for WrapperWithExtraField<T>
  11 where
  12     T: DispatchFromDyn<U>,
  13 {} //~^^^ ERROR [E0378]
  14
  15
  16 struct MultiplePointers<T: ?Sized>{
  17     ptr1: *const T,
  18     ptr2: *const T,
  19 }
  20
  21 impl<T: ?Sized, U: ?Sized> DispatchFromDyn<MultiplePointers<U>> for MultiplePointers<T>
  22 where
  23     T: Unsize<U>,
  24 {} //~^^^ ERROR [E0378]
  25
  26
  27 struct NothingToCoerce<T: ?Sized> {
  28     data: PhantomData<T>,
  29 }
  30
  31 impl<T: ?Sized, U: ?Sized> DispatchFromDyn<NothingToCoerce<T>> for NothingToCoerce<U> {}
  32 //~^ ERROR [E0378]
  33
  34 #[repr(C)]
  35 struct HasReprC<T: ?Sized>(Box<T>);
  36
  37 impl<T: ?Sized, U: ?Sized> DispatchFromDyn<HasReprC<U>> for HasReprC<T>
  38 where
  39     T: Unsize<U>,
  40 {} //~^^^ ERROR [E0378]
  41
  42 #[repr(align(64))]
  43 struct OverAlignedZst;
  44 struct OverAligned<T: ?Sized>(Box<T>, OverAlignedZst);
  45
  46 impl<T: ?Sized, U: ?Sized> DispatchFromDyn<OverAligned<U>> for OverAligned<T>
  47     where
  48         T: Unsize<U>,
  49 {} //~^^^ ERROR [E0378]
  50
  51 fn main() {}