bad autoconf variable names

if test "$ac_cv_header_sys_epoll_h" = yes -a "$ac_cv_func_epoll_ctl" = yes; then
  AC_DEFINE([HAVE_EPOLL], [1], [Define if you have epoll support.])
fi

if test "$ac_cv_header_sys_event_h" = yes -a "$ac_cv_func_kqueue" = yes; then
  AC_DEFINE([HAVE_KQUEUE], [1], [Define if you have kqueue support.])

  AC_CHECK_SIZEOF([kev.filter], [], [#include <sys/event.h>
struct kevent kev;])

  AC_CHECK_SIZEOF([kev.flags], [], [#include <sys/event.h>
struct kevent kev;])
fi

if test "$ac_cv_header_poll_h" = yes -a "$ac_cv_func_poll" = yes; then
  AC_DEFINE([HAVE_POLL], [1], [Define if you have poll support.])
fi

The AC_DEFINE lines for HAVE_KQUEUE and HAVE_POLL don't do anything, because earlier we have

AC_CHECK_FUNCS([epoll_ctl eventfd kevent kevent64 kqueue poll])

and that already defines HAVE_KQUEUE (and sets ac_cv_func_kqueue) when the kqueue function is found.

Not entirely sure what the right thing to do is here, do we rely on having a prototype for kqueue in sys/event.h specifically? Technically that wouldn't be what we check for even if we used a renamed HAVE_KQUEUE variable.

AFAIK this doesn't cause any real problems except that it really confused me when I tried to simulate not having poll by moving /usr/include/poll.h away temporarily.

Trac metadata

Trac field	Value
Version	7.9
Type	Bug
TypeOfFailure	OtherFailure
Priority	low
Resolution	Unresolved
Component	libraries/base
Test case
Differential revisions
BlockedBy
Related
Blocking
CC	ekmett, hvr
Operating system
Architecture