The checkpoint list is maintained as an array of WT_CKPT. It is allocated/reallocated without always maintaining an allocation size. When freeing the array, we walk the list freeing individual checkpoints and terminate the walk at NULL ckpt->name, or ckpt->order fields. We do so because based on the order of initialization, one of these fields will always be populated, unless we have a failure while populating these fields themselves.

This list termination is ending up prone to bugs and unnecessarily complicated and we can instead do better by introducing a field in WT_CKPT that reflects the end of the checkpoint list.

Note: This became apparent as a review comment in WT-7381.