error[E0453]: allow(unsafe_code) incompatible with previous forbid
  --> $DIR/reasons-forbidden.rs:23:13
   |
LL |     unsafe_code,
   |     ----------- `forbid` level set here
...
LL |     #[allow(unsafe_code)]
   |             ^^^^^^^^^^^ overruled by previous forbid
   |
   = note: our errors & omissions insurance policy doesn't cover unsafe Rust

error: usage of an `unsafe` block
  --> $DIR/reasons-forbidden.rs:27:5
   |
LL | /     unsafe {
LL | |
LL | |
LL | |         *a_billion_dollar_mistake
LL | |     }
   | |_____^
   |
   = note: our errors & omissions insurance policy doesn't cover unsafe Rust
note: the lint level is defined here
  --> $DIR/reasons-forbidden.rs:12:5
   |
LL |     unsafe_code,
   |     ^^^^^^^^^^^

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0453`.