error: where clauses are not allowed before the type for type aliases
  --> $DIR/leading-where-clause.rs:9:1
   |
LL | / where
LL | |     String: From<T>,
   | |____________________^
   |
   = note: see issue #89122 <https://github.com/rust-lang/rust/issues/89122> for more information
help: move it to the end of the type declaration
   |
LL + 
LL ~ = T where String: From<T>;
   |

error: aborting due to previous error