Re: [mp1] Linking confusion

[prev] [thread] [next] [Date index for 2004/12/30]

William McKee wrote:
> Hi folks,
> 
> I'm trying to recompile Perl and Apache/mod_perl on a Debian Sarge
> system using the following versions:
> 
>  Perl 5.8.6
>  Apache 1.3.33
>  mod_perl 1.29
> 
> I am compiling mod_perl statically (using Apachetoolbox) with the
> following options:
> 
>     APACHE_PREFIX=/usr/local/apache
>     APACHE_SRC=/usr/local/src/Apachetoolbox-1.5.72/apache_1.3.33/src
>     SSL_BASE=
>     APACI_ARGS='--enable-module=rewrite'
>     DO_HTTPD=1
>     USE_APACI=1
>     EVERYTHING=1
> 
> During compilation of mod_perl, I was seeing undefined reference errors
> which are nicely described on the install page[1]. The prescription
> suggests rebuilding Perl with dynamic linking; apparently the version
> that's shipped with Debian is not dynamically linked(?). Sounds fine,
> but I'm not a C programmer so am not sure exactly what this means.

Now that you know what does it take, please send a patch that extends [1] 
to explain how to do that.

>>From what I could find reading the INSTALL document that comes with the
> Perl source, I need to recompile with the -Duseshrplib compile-time
> option. My understanding is that this option will build a libperl.so
> file. Is this correct? Am I taking the right action to build a dynamic
> Perl?

That's correct.

> With that option, I am able to compile Apache with mod_perl. Now though,
> when starting the newly compiled server, I'm receiving relocation errors
> which appear to be due to multiple versions of libperl.so/libperl.a (not
> sure which).
> 
> While browsing the net for possible solutions, I came across the
> troubleshooting document[2]. It seems to say that if 'perl
> -V:useshrplib' returns true, then Perl is statically linked. Is this
> correct? It seems opposite of what I'd expect from reading the INSTALL
> document.

Right, it's a docbug, fixed in svn.

> I'm pretty much at wits end as to why I'm receiving relocation errors.
> The best I can figure is some kind of binary incompatibility between the
> version of Perl that I've compiled and previously compiled libraries.
> I've tried reinstalling some of the XS modules such as DBI which seems
> to clear up these errors.
> 
> Any other suggestions or pointers, esp. in light of the differences
> between dynamic and static linking and libperl.so/libperl.a, would be
> much appreciated.

As [2] explains you have more than one libperl.so and the wrong one gets 
loaded. libperl.so should *not* be in /usr/lib or any other globally seen 
loader path if you want to have more than one perl on the same system. 
Unfortunately some distros don't get it and install libperl.(so|a) into 
/usr/lib :(

> [1] http://perl.apache.org/docs/1.0/guide/install.html#Undefined_reference_to__PL_perl_destruct_level_
> [2] http://perl.apache.org/docs/1.0/guide/troubleshooting.html#_relocation_errors__or__undefined_symbol_
> 


        -- 
        __________________________________________________________________
Stas Bekman            JAm_pH ------> Just Another mod_perl Hacker
http://stason.org/     mod_perl Guide ---> http://perl.apache.org
mailto:stas@xxxxxx.xxx http://use.perl.org http://apacheweek.com
http://modperlbook.org http://apache.org   http://ticketmaster.com

-- 
Report problems: http://perl.apache.org/bugs/
Mail list info: http://perl.apache.org/maillist/modperl.html
List etiquette: http://perl.apache.org/maillist/email-etiquette.html