Re: [Plplot-devel] libqhull

[Rafael L. <lab...@ps...>]

* João Cardoso <jc...@fe...> [2003-03-14 15:36]:

> But won't this happens in other non-debian systems that have 
> qhull/freetype installed as archive and not shared libraries? And even if a
> shared library exists but it was not built with libtool?

Oh, I guess you are confused here.  *.la files are _not_ static libraries.
Neither are they shared libs.  Actually, they are ... shell scripts (!!!)

It only makes sense to use *.la files as arguments of libtool (or, in our
case, plplot_libtool).  I dislike the idea of using that script
(plplot_libtool) to compile the examples, but Alan seems to have strong
arguments in favor of it, mainly related to portability.

> The configure test that checks for the presence of qhull just checks 
> that a program can be compiled with -lqhull, it does not check if it is 
> a shared/archive library. If latter in the configure process  -lqhull 
> is replaced with <absolute_path>/libqhull.la that will break the make.

No, configure never replaces -lqhull by <absolute_path>/libqhull.la.  This
is done internally by libtool when generating the libplplot{d}.la file (look
at the line starting with "dependency_libs=").  See below.

> Does the current plplot configure scheme address this issue? I have only 
> tested with shared libs.

This is not a matter of shared vs. static libraries, as I pointed out above.

At any rate, this will not be a real problem, since if the user does not
have libqhull.la installed in her system, then "-lqhull" gets inserted into
libplplot{d}.la. To be convinced, just do it by yourself:

    $ cd /usr/lib
    $ mv libqhull.la libqhull.la-save
    $ cd ~/plplot-build/src
    $ rm libplplotd.la
    $ make > /dev/null    
    $ grep dependency_libs libplplotd.la
    dependency_libs='/usr/lib/libfreetype.la -lz 
    /home/rafael/plplot-build/lib/csa/libcsa.la
    /home/rafael/devel/plplot-build/lib/nn/libnn.la -lqhull -lm -ldl'
                                                    ^^^^^^^
    $ cd /usr/lib
    $ mv libqhull.la-save libqhull.la
    $ cd ~/plplot-build/src
    $ rm libplplotd.la
    $ make > /dev/null    
    $ grep dependency_libs libplplotd.la
    dependency_libs='/usr/lib/libfreetype.la -lz 
    /home/rafael/plplot-build/lib/csa/libcsa.la
    /home/rafael/devel/plplot-build/lib/nn/libnn.la
    /usr/lib/libqhull.la -lm -ldl'
    ^^^^^^^^^^^^^^^^^^^^

-- 
Rafael