# Function alloc::heap::deallocate [−] [src]

    pub unsafe fn deallocate(ptr: *mut u8, old_size: usize, align: usize)

🔬 This is a nightly-only experimental API. (`heap_api` #27700)

the precise API and guarantees it provides may be tweaked slightly, especially to possibly take into account the types being stored to make room for a future tracing garbage collector

Deallocates the memory referenced by `ptr`.

The `ptr` parameter must not be null.

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

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