Re: find libxml2 using pkg-config

On Sun, Mar 03, 2013 at 10:30:11PM -0500, Peter Eisentraut wrote:
> On Fri, 2013-03-01 at 14:25 -0500, Noah Misch wrote:
> > On Mon, Jan 14, 2013 at 06:51:05AM -0500, Peter Eisentraut wrote:
> > > In multi-arch OS installations, using a single foo-config script to
> > find
> > > libraries is problematic, because you don't know which architecture
> > it
> > > will point to, and you can't choose which one you want.  Using
> > > pkg-config is better in that situation, because you can use its
> > > environment variables to point to your preferred version
> > > of /usr/lib*/pkgconfig or similar.
> > 
> > "./configure XML2_CONFIG=/my/preferred/xml2-config" achieves this
> > today. 
> 
> No.
> 
> The way multi-arch installations work is that you have the libraries
> under /usr/lib and /usr/lib64, or /usr/lib/$arch1 and /usr/lib/$arch2,
> but only one /usr/bin.  So there cannot be two foo-config scripts to
> cover this.  There is, however, /usr/lib/pkgconfig
> and /usr/lib64/pkgconfig (or analogous), so pkg-config can handle this.

Do you have in mind a target system exhibiting a problem?  CentOS 6 ships a
single xml2-config, but its --cflags --libs output is the same regardless of
the installed combination of libxml2-dev packages.  Ubuntu 13.04 does not ship
32-bit libxml2, so it avoids the question.

-- 
Noah Misch
EnterpriseDB                                 http://www.enterprisedb.com