error[E0425]: cannot find value `num` in this scope
  --> $DIR/ice-unwrap-probe-many-result-125876.rs:4:24
   |
LL |     std::ptr::from_ref(num).cast_mut().as_deref();
   |                        ^^^ not found in this scope

warning: type annotations needed
  --> $DIR/ice-unwrap-probe-many-result-125876.rs:4:29
   |
LL |     std::ptr::from_ref(num).cast_mut().as_deref();
   |                             ^^^^^^^^
   |
   = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2018!
   = note: for more information, see issue #46906 <https://github.com/rust-lang/rust/issues/46906>
   = note: `#[warn(tyvar_behind_raw_pointer)]` on by default

warning: type annotations needed
  --> $DIR/ice-unwrap-probe-many-result-125876.rs:4:40
   |
LL |     std::ptr::from_ref(num).cast_mut().as_deref();
   |                                        ^^^^^^^^
   |
   = warning: this is accepted in the current edition (Rust 2015) but is a hard error in Rust 2018!
   = note: for more information, see issue #46906 <https://github.com/rust-lang/rust/issues/46906>

error[E0599]: no method named `as_deref` found for raw pointer `*mut _` in the current scope
  --> $DIR/ice-unwrap-probe-many-result-125876.rs:4:40
   |
LL |     std::ptr::from_ref(num).cast_mut().as_deref();
   |                                        ^^^^^^^^
   |
help: there is a method `as_ref` with a similar name
   |
LL |     std::ptr::from_ref(num).cast_mut().as_ref();
   |                                        ~~~~~~

error: aborting due to 2 previous errors; 2 warnings emitted

Some errors have detailed explanations: E0425, E0599.
For more information about an error, try `rustc --explain E0425`.