(Originally raised by geert.bosch@mongodb.com)

wt_modify_apply_item takes a void * argument for the modify structure. It then passes it to the WT_MODIFY_FOREACH_BEGIN macro, which contains a bunch of code like this:

memcpy(&(mod).data.size, __p, sizeof(size_t));
__p += sizeof(size_t);

In other words, manual deserialisation. It may be the case that this code is the first chance we get to deserialise these structures, in which case it's probably legitimate. But I'm not sure and it would really improve the readability of this code if we could just use a structure.