Rollup merge of #22843 - vhbit:no-jemalloc-fix, r=alexcrichton

   "body": null,

Author: Manishearth

src/liballoc/heap.rs

@@ -300,7 +300,7 @@ mod imp {
             libc::realloc(ptr as *mut libc::c_void, size as libc::size_t) as *mut u8
         } else {
             let new_ptr = allocate(size, align);
-            ptr::copy_memory(new_ptr, ptr, cmp::min(size, old_size));
+            ptr::copy(new_ptr, ptr, cmp::min(size, old_size));
             deallocate(ptr, old_size, align);
             new_ptr
         }