warning: function pointer comparisons do not produce meaningful results since their addresses are not guaranteed to be unique
  --> $DIR/fn-ptr-comparisons-some.rs:12:13
   |
LL |     let _ = Some::<FnPtr>(func) == Some(func as unsafe extern "C" fn());
   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: the address of the same function can vary between different codegen units
   = note: furthermore, different functions could have the same address after being merged together
   = note: for more information visit <https://doc.rust-lang.org/nightly/core/ptr/fn.fn_addr_eq.html>
   = note: `#[warn(unpredictable_function_pointer_comparisons)]` on by default

warning: 1 warning emitted