On Tue, Jun 24, 2025 at 1:29 PM Peter Eisentraut <pe...@eisentraut.org> wrote: > Note that Autoconf uses a compilation test, not a preprocessor test, for > its AC_CHECK_HEADERS, so it uses .check_header() semantics. And this > was the result of a long transition, because the compile test was > ultimately deemed to be better. So in general, I would be wary about > moving away from .check_header() toward .has_header(). But it looks > like meson.build mixes those without much of a pattern, so maybe it > doesn't matter for now.
I don't mind moving in that direction, but I do want the two sides to match. So if it was good enough up to this point to use has_header() for our feature macros, I don't think I want to try to change that for 18. > But I'm also suspicious, because by this explanation, the > AC_CHECK_HEADERS calls on sys/event.h should fail on OpenBSD, but they > do not on the existing buildfarm members. I think Andres tracked that discrepancy down [1]: > Gah, configure does pass - because AC_CHECK_HEADER(), if includes is not > passed > in, first includes what's defined in AC_INCLUDES_DEFAULT. Thanks! --Jacob [1] https://www.postgresql.org/message-id/637haqqyhg2wlz7q6wq25m2qupe67g7f2uupngzui64zypy4x2%40ysr2xnmynmu4
