why lines 46 and 59 can't be relaxed in treiber stack

[hydium]

Thread 1

Thread 2

pub fn push(&self, t: T) { let mut n = Owned::new(Node { data: ManuallyDrop::new(t), next: Atomic::null(), }); let guard = epoch::pin(); loop { let head = self.head.load(Relaxed, &guard); match self.head.compare_and_set(head, n, Release, &guard) { <- A n.next.store(head, Relaxed); //<- if A or B are relaxed this operation can be here //it was before the compare_and_set originally Ok(_) => break, Err(e) => n = e.new, } } }

pub fn pop(&self) -> Option<T> { let guard = epoch::pin(); loop { let head = self.head.load(Acquire, &guard); //<- B, if this load is relaxed //this head has a null next pointer because the pointer is set later