The accumulator is used in BasicOrderFulfiller, OrderFulfiller and OrderCombiner. It is a variable length array, but does not have a properly allocated memory space. It can be grown using _insert and _trigger will flush it.
The problem is it is placed at the free memory pointer, but the pointer is not increment if it would grow beyond its initial capacity. The initial capacity is AccumulatorDisarmed aka 32. In the use cases it seems at most 2 entries are inserted.
Instead of relying that this memory space is never overwritten, it may make sense pre-allocating a fixed structure. The current implementation can break on compiler upgrades or changes in the function layouts.
Context: BasicOrderFulfiller, OrderFulfiller, OrderCombiner, _insert, _trigger
Avoid using the non-memory allocating accumulator design.
