src/libcore/unsafe.rs


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/*
Module: unsafe

Unsafe operations
*/

#[abi = "rust-intrinsic"]
native mod rusti {
    fn cast<T, U>(src: T) -> U;
}

#[abi = "cdecl"]
native mod rustrt {
    fn leak<T>(-thing: T);
}

/*
Function: reinterpret_cast

Casts the value at `src` to U. The two types must have the same length.
*/
unsafe fn reinterpret_cast<T, U>(src: T) -> U {
    let t1 = sys::get_type_desc::<T>();
    let t2 = sys::get_type_desc::<U>();
    if (*t1).size != (*t2).size {
        fail "attempt to cast values of differing sizes";
    }
    ret rusti::cast(src);
}

/*
Function: leak

Move `thing` into the void.

The leak function will take ownership of the provided value but neglect
to run any required cleanup or memory-management operations on it. This
can be used for various acts of magick, particularly when using
reinterpret_cast on managed pointer types.
*/
unsafe fn leak<T>(-thing: T) { rustrt::leak(thing); }