error: unconstrained generic constant
  --> $DIR/issue-51892.rs:14:17
   |
LL |     type Type = [u8; std::mem::size_of::<<T as Trait>::Type>()];
   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
help: try adding a `where` bound
   |
LL |     type Type = [u8; std::mem::size_of::<<T as Trait>::Type>()] where [(); std::mem::size_of::<<T as Trait>::Type>()]:;
   |                                                                 ++++++++++++++++++++++++++++++++++++++++++++++++++++++

error: aborting due to 1 previous error