Tony Griffiths <tony(dot)griffiths(at)cs(dot)man(dot)ac(dot)uk> writes:
> I've looked in fmgr.h and there is no definition of this type there - it
> uses the type, but does not define it.
Eh?
typedef Datum (*PGFunction) (FunctionCallInfo fcinfo);
Looks like a definition to me ...
regards, tom lane