Re: [v9.1] sepgsql - userspace access vector cache

On Fri, Aug 19, 2011 at 9:59 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Kohei KaiGai <kaigai@kaigai.gr.jp> writes:
>> 2011/8/18 Robert Haas <robertmhaas@gmail.com>:
>>> Actually, as I look at this more, I think this build system is
>>> completely mis-designed.  Given that you want to build sepgsql,
>>> selinux is not an optional feature.  So the stuff in
>>> contrib/sepgsql/Makefile that is intended to link against libselinux
>>> only if --with-selinux was specified at configure time is nonsense.
>
> What stuff is that?

SHLIB_LINK += $(filter -lselinux, $(LIBS))

> This patch seems unnecessary to me.  The way it works now appears to be
> quite parallel to the way that contrib/xml2 works, and has worked for
> years.  I don't think that sepgsql should behave differently from that.

Hmm.  I see now that it's parallel, but I find it pretty confusing
that building sepgsql without specifying --with-selinux results in a
shared library that seems to compile OK but won't load.   Why not
just:

SHLIB_LINK = -lselinux

Similarly, in the case of xml2 we have:

SHLIB_LINK += $(filter -lxslt, $(LIBS)) $(filter -lxml2, $(LIBS))

For xslt, it probably makes sense to filter it out if it wasn't found,
because the code has ifdefs for USE_XSLT that do something sensible if
the library is not there.  But I fail to see what the point is of
filtering out xml2, because surely we're doomed if that's not there...
or am I confused?

--
Robert Haas
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