Function alloc::heap::reallocate [] [src]

pub unsafe fn reallocate(ptr: *mut u8, old_size: usize, size: usize, align: usize) -> *mut u8
Unstable

Resize the allocation referenced by ptr`ptrto` to size`size` bytes.

On failure, return a null pointer and leave the original allocation intact.

If the allocation was relocated, the memory at the passed-in pointer is undefined after the call.

Behavior is undefined if the requested size is 0 or the alignment is not a power of 2. The alignment must be no larger than the largest supported page size on the platform.

The old_size`old_sizeand` and align`alignparameters are the parameters that were used to create the allocation referenced by` parameters are the parameters that were used to create the allocation referenced by ptr`ptr. The`. The old_size`old_size` parameter may be any value in range_inclusive(requested_size, usable_size).