| // This upcast is currently forbidden because it involves an invalid value. |
| // However, if in the future we relax the validity requirements for raw pointer vtables, |
| // we could consider allowing this again -- the cast itself isn't doing anything wrong, |
| // only the transmutes needed to set up the testcase are wrong. |
| |
| use std::fmt; |
| |
| fn main() { |
| // vtable_mismatch_nop_cast |
| let ptr: &dyn fmt::Display = &0; |
| let ptr: *const (dyn fmt::Debug + Send + Sync) = unsafe { std::mem::transmute(ptr) }; //~ERROR: wrong trait |
| // Even though the vtable is for the wrong trait, this cast doesn't actually change the needed |
| // vtable so it should still be allowed -- if we ever allow the line above. |
| let _ptr2 = ptr as *const dyn fmt::Debug; |
| } |
