Re: Request for Patch Feedback: Lag & Lead Window Functions Can Ignore Nulls

...which gives a proper bitmap. It's hard to break this into a factory method like bms_make_singleton as I'm getting the (zero'ed) partition local memory from one call, then forcing a correct bitmap's structure on it. Maybe bitmapset.h needs an bms_initialise(void *, int num_words) factory method? You'd still have to use the BITMAPSET_SIZE macro to get the correct amount of memory for the void*. Maybe the factory method could take a function pointer that would allocate memory of the given size (e.g. Bitmapset* initialize(void* (allocator)(Size_t), int num_words) ) - this means I could still use the partition's local memory.

I don't think the solution would be tidier if I re-instated the leadlag_context struct with a single Bitmapset member. Other Bitmapset usage seems to just call bms_make_singleton then bms_add_member over and over again - which afaict will call palloc every BITS_PER_BITMAPWORD calls, which is not really what I want.