On 2021-Jun-18, Tom Lane wrote: > Alvaro Herrera <alvaro.herr...@2ndquadrant.com> writes: > > So I'm +1 on adding this "feature macro". > > Concretely, how about the attached?
Seems OK to me. We can just accumulate any similar ones in the future nearby. > (I also got rid of a recently-added > extra comma. While the compilers we use might not warn about that, > it seems unwise to assume that no user's compiler will.) Oops. > I guess one unresolved question is whether we want to mention these in > the SGML docs. I vote "no", because it'll raise the maintenance cost > noticeably. But I can see an argument on the other side. Well, if we do want docs for these macros, then IMO it'd be okay to have them in libpq-fe.h itself rather than SGML. A one-line comment for each would suffice: +/* + * These symbols may be used in compile-time #ifdef tests for the availability + * of newer libpq features. + */ +/* Indicates presence of PQenterPipelineMode and friends */ +#define LIBPQ_HAS_PIPELINING 1 + +/* Indicates presence of PQsetTraceFlags; PQtrace changed output format */ +#define LIBPQ_HAS_TRACE_FLAGS 1 -- Álvaro Herrera 39°49'30"S 73°17'W
