[xml/sgml-pkgs] Bug#670572: Bug#670572: libxml2: missing link from /usr/lib

[Stefan Fritsch]

On Friday 27 April 2012, Aron Xu wrote:
> clone 670572 -1
> retitle -1 not usable because libxml2.so.* are moved to Multi-Arch
> path severity -1 serious
> reassign -1 src:mod-proxy-html
> block 670572 by -1
> thanks
> 
> On Thu, Apr 26, 2012 at 21:39, Francesco Potortì 
<Potorti at isti.cnr.it> wrote:
> > Package: libxml2
> > Version: 2.7.8.dfsg-9
> > Severity: normal
> > 
> > In order to have Apache module proxy_html work, I had to do
> > 
> > # ln -s /usr/lib/x86_64-linux-gnu/libxml2.so.2
> > /usr/lib/libxml2.so.2
> 
> Cloned the bug and reassigned to mod-proxy-html and CC'ed Apache
> maintainers to the thread. I'm wondering if this is a single case
> of problem in mod-proxy-html or a more general one for other
> Apache modules.

This may hit more modules. Ubuntu has a similar bug report for 
mod_security (LP 988819).


> I'm not convinced to add such a link, as it could be harmful for
> other applications when you have more than one architectures
> installed.

I agree, such a link should be avoided.

I see two possible solutions:

- Make the result of "dpkg-architecture -qDEB_HOST_MULTIARCH" 
available as envvar, so that modules can use it in their config. E.g.
"LoadFile /usr/lib/${DEB_HOST_MULTIARCH}/libxml2.so.2". This would 
break with non-multiarch versions of libxml2, but that's acceptable.

- Make the module actually link against the libraries that it uses. 
This can cause havoc if different versions of the same library are 
pulled, but I think this should normally not happen in Debian. FWIW, 
this is the approach taken with the mod_proxy_html included in apache2 
2.4.

I prefer the second option but if some module maintainers want to use 
the first option, that's ok with me, too.