src/test/ui/const-generics/const-argument-if-length.full.stderr

   1 error[E0277]: the size for values of type `T` cannot be known at compilation time
   2   --> $DIR/const-argument-if-length.rs:15:12
   3    |
   4 LL | pub struct AtLeastByte<T: ?Sized> {
   5    |                        - this type parameter needs to be `std::marker::Sized`
   6 LL |     value: T,
   7    |            ^ doesn't have a size known at compile-time
   8    |
   9    = note: only the last field of a struct may have a dynamically sized type
  10    = help: change the field's type to have a statically known size
  11 help: consider removing the `?Sized` bound to make the type parameter `Sized`
  12    |
  13 LL - pub struct AtLeastByte<T: ?Sized> {
  14 LL + pub struct AtLeastByte<T> {
  15    |
  16 help: borrowed types always have a statically known size
  17    |
  18 LL |     value: &T,
  19    |            +
  20 help: the `Box` type always has a statically known size and allocates its contents in the heap
  21    |
  22 LL |     value: Box<T>,
  23    |            ++++ +
  24
  25 error: unconstrained generic constant
  26   --> $DIR/const-argument-if-length.rs:17:10
  27    |
  28 LL |     pad: [u8; is_zst::<T>()],
  29    |          ^^^^^^^^^^^^^^^^^^^
  30    |
  31    = help: try adding a `where` bound using this expression: `where [(); is_zst::<T>()]:`
  32
  33 error: aborting due to 2 previous errors
  34
  35 For more information about this error, try `rustc --explain E0277`.