Current OpenBSD is at 4.7 with a new release every six months.
diff below:

--- configure  Mon Jun  8 17:22:57 2009
+++ configure.new Wed Feb 10 16:00:34 2010
@@ -2086,7 +2086,7 @@
   # On OpenBSD, select(2) is not available if _XOPEN_SOURCE is defined,
   # even though select is a POSIX function. Reported by J. Ribbens.
   # Reconfirmed for OpenBSD 3.3 by Zachary Hamm, for 3.4 by Jason Ish.
-  OpenBSD/2.* | OpenBSD/3.[0123456789] | OpenBSD/4.[0123])
+  OpenBSD/2.* | OpenBSD/3.* | OpenBSD/4.[01234567])
     define_xopen_source=no
     # OpenBSD undoes our definition of __BSD_VISIBLE if _XOPEN_SOURCE is
     # also defined. This can be overridden by defining _BSD_SOURCE

Thanks for reporting. This looks like a duplicate of issue3920.

John> Current OpenBSD is at 4.7 with a new release every six months.
    John> diff below:
    ...
    John> -  OpenBSD/2.* | OpenBSD/3.[0123456789] | OpenBSD/4.[0123])
    John> +  OpenBSD/2.* | OpenBSD/3.* | OpenBSD/4.[01234567])

Wouldn't it be better to just use "OpenBSD/4.*" and fix it if/when a new
minor release makes the assumption false?

Skip

Yeah or better yet take out the versioning entirely.

>> Yeah or better yet take out the versioning entirely.

Perhaps.  Is 1.x treated differently than 2, 3 or 4?

S

Perhaps 1.x was never considered.  OpenBSD 2.0 was released in 1996.  The OS developers only support the current release version and one "minor" release back anyway.  The major release number isn't significant.  It's just incremented after the "minor" release is bumped from 9.  There's a release every six months so the difference in "major" release numbers is 5 years.  No one should even be running 3.x or even early 4.x anymore.

This issue is now superseded by issue 3920. It would be good if somebody could confirm that the approach taken for 4.4 continues to work in more recent releases.

In my testing of issue 3920 I missed that the original approach also
fixed the ncurses.h problem, so it should be preferred over bsd3.diff.

I attach a patch that reverts the recent commit and extends the
xopen_source=no up to version 4.9. I've tested it on 4.4 and 4.6,
johns did essentially the same on 4.7.

I agree with Skip and johns that at least all 4.* versions should be covered, otherwise we have this situation every 6 months.

Stefan, what ncurses problem are you referring to?

I quite object to working around OpenBSD limitations, and would rather hope that OpenBSD fixes their POSIX support at some point.

On OpenBSD the ncurses.h header has been broken for quite some time,
see e.g. http://bugs.python.org/issue1244610. The problem is that
when _XOPEN_SOURCE_EXTENDED is defined, wchar_t is defined twice.
I can confirm that it is still broken on 4.6, but it appears that
it has been fixed in current.

So I propose to use the old method up to 4.6, and use the new method
from 4.7 on. I attach a patch that has been tested on an OpenBSD
snapshot (which will become version 4.7).

Thanks for the tests, and the patch. Committed as r78202, r78203, r78204, and r78205.