Use our own getopt() on OpenBSD.

Recent OpenBSD (at least 5.9 and up) has a version of getopt(3)
that will not cope with the "-:" spec we use to accept double-dash
options in postgres.c and postmaster.c.  Admittedly, that's a hack
because POSIX only requires getopt() to allow alphanumeric option
characters.  I have no desire to find another way, however, so
let's just do what we were already doing on Solaris: force use
of our own src/port/getopt.c implementation.

In passing, improve some of the comments around said implementation.

Per buildfarm and local testing.  Back-patch to all supported branches.

Discussion: https://postgr.es/m/30197.1547835700@sss.pgh.pa.us

1 files changed, 3 insertions, 3 deletions

diff --git a/configure b/configure
index 5e4204ae93..67ba8b677a 100755
--- a/configure
+++ b/configure
@@ -15912,9 +15912,9 @@ esac
 
 fi
 
-# Solaris' getopt() doesn't do what we want for long options, so always use
-# our version on that platform.
-if test "$PORTNAME" = "solaris"; then
+# On OpenBSD and Solaris, getopt() doesn't do what we want for long options
+# (i.e., allow '-' as a flag character), so use our version on those platforms.
+if test "$PORTNAME" = "openbsd" -o "$PORTNAME" = "solaris"; then
   case " $LIBOBJS " in
   *" getopt.$ac_objext "* ) ;;
   *) LIBOBJS="$LIBOBJS getopt.$ac_objext"