Function std::intrinsics::drop_in_place

#[lang = "drop_in_place"]
pub unsafe fn drop_in_place<T>(to_drop: *mut T) where
    T: ?Sized, 

Executes the destructor (if any) of the pointed-to value.

This has two use cases:

• It is required to use drop_in_place to drop unsized types like trait objects, because they can't be read out onto the stack and dropped normally.

• It is friendlier to the optimizer to do this over ptr::read when dropping manually allocated memory (e.g. when writing Box/Rc/Vec), as the compiler doesn't need to prove that it's sound to elide the copy.

Safety

This has all the same safety problems as ptr::read with respect to invalid pointers, types, and double drops.