Paul A Jungwirth <pj(at)illuminatedcomputing(dot)com> writes:
> Is it expected for flinfo to be null when using DirectFunctionCall*?
Yes, per the comment on those functions:
* These are for invocation of a specifically named function with a
* directly-computed parameter list. Note that neither arguments nor result
* are allowed to be NULL. Also, the function cannot be one that needs to
* look at FmgrInfo, since there won't be any.
> Is there something else I should use instead? It looks like
> FunctionCall2 would let me pass my own flinfo, but I'm not sure how to
> set that up first.
Use fmgr_info() or a sibling to fill in the FmgrInfo.
regards, tom lane