pub unsafe fn increment_strong_count(ptr: *const T) {
        // Retain Arc, but don't touch refcount by wrapping in ManuallyDrop
        let arc = unsafe { mem::ManuallyDrop::new(Arc::<T>::from_raw(ptr)) };
        // Now increase refcount, but don't drop new refcount either
        let _arc_clone: mem::ManuallyDrop<_> = arc.clone();
    }
Returns `true` if the two `Arc`s point to the same allocation
(in a vein similar to [`ptr::eq`]).

# Examples

```
use std::sync::Arc;

let five = Arc::new(5);
l
benchmarks/haystacks/code/rust-library.rs