error: generic parameters may not be used in const operations
  --> $DIR/issue-66205.rs:7:14
   |
LL |     fact::<{ N - 1 }>();
   |              ^ cannot perform const operation using `N`
   |
   = help: const parameters may only be used as standalone arguments, i.e. `N`
   = help: use `#![feature(const_generics)]` and `#![feature(const_evaluatable_checked)]` to allow generic const expressions

error: aborting due to previous error