error: Undefined Behavior: trying to set discriminant of a Option<std::num::NonZero<i32>> to the niched variant, but the value does not match
  --> tests/fail/enum-set-discriminant-niche-variant-wrong.rs:LL:CC
   |
LL |             SetDiscriminant(*ptr, 1);
   |             ^^^^^^^^^^^^^^^^^^^^^^^^ Undefined Behavior occurred here
   |
   = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
   = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
   = note: BACKTRACE:
   = note: inside `set_discriminant` at tests/fail/enum-set-discriminant-niche-variant-wrong.rs:LL:CC
note: inside `main`
  --> tests/fail/enum-set-discriminant-niche-variant-wrong.rs:LL:CC
   |
LL |     set_discriminant(&mut v);
   |     ^^^^^^^^^^^^^^^^^^^^^^^^

note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace

error: aborting due to 1 previous error