[breaking-change] change the box_free item to accept pointers to unsized types

This commit is contained in:
Oliver 'ker' Schneider 2016-11-11 11:55:47 +01:00
parent 3ac9ec7dfd
commit 323c20c8a4
2 changed files with 7 additions and 6 deletions

View File

@ -46,8 +46,8 @@ unsafe fn deallocate(ptr: *mut u8, _size: usize, _align: usize) {
}
#[lang = "box_free"]
unsafe fn box_free<T>(ptr: *mut T) {
deallocate(ptr as *mut u8, ::core::mem::size_of::<T>(), ::core::mem::align_of::<T>());
unsafe fn box_free<T: ?Sized>(ptr: *mut T) {
deallocate(ptr as *mut u8, ::core::mem::size_of_val(&*ptr), ::core::mem::align_of_val(&*ptr));
}
#[start]

View File

@ -17,7 +17,7 @@
use core::{isize, usize};
#[cfg(not(test))]
use core::intrinsics::{min_align_of, size_of};
use core::intrinsics::{min_align_of_val, size_of_val};
#[allow(improper_ctypes)]
extern "C" {
@ -152,11 +152,12 @@ unsafe fn exchange_free(ptr: *mut u8, old_size: usize, align: usize) {
#[cfg(not(test))]
#[lang = "box_free"]
#[inline]
unsafe fn box_free<T>(ptr: *mut T) {
let size = size_of::<T>();
unsafe fn box_free<T: ?Sized>(ptr: *mut T) {
let size = size_of_val(&*ptr);
let align = min_align_of_val(&*ptr);
// We do not allocate for Box<T> when T is ZST, so deallocation is also not necessary.
if size != 0 {
deallocate(ptr as *mut u8, size, min_align_of::<T>());
deallocate(ptr as *mut u8, size, align);
}
}