error[E0658]: comparing raw pointers inside constant
  --> $DIR/issue-25826.rs:3:30
   |
LL |     const A: bool = unsafe { id::<u8> as *const () < id::<u16> as *const () };
   |                              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: see issue #53020 <https://github.com/rust-lang/rust/issues/53020> for more information
   = help: add `#![feature(const_compare_raw_pointers)]` to the crate attributes to enable

error: aborting due to previous error

For more information about this error, try `rustc --explain E0658`.