TRACE("s1", "sl_cas: found an item %p in the skiplist that matched the key. the expectation was "
"not met, the skiplist was not changed", old_item, old_item_val);
return old_item_val; // failure
TRACE("s1", "sl_cas: found an item %p in the skiplist that matched the key. the expectation was "
"not met, the skiplist was not changed", old_item, old_item_val);
return old_item_val; // failure