Re: using .la or .a when linking an executable ?

[Vincent Torri]

Hey,

Sorry, Ralf, i've just deleted your answer. It was embedded in a lot of 
spams... I paste it below.


> Hello Vincent,

> * Vincent Torri wrote on Sun, Sep 28, 2008 at 01:04:44PM CEST:
> > eet_LDADD = $(top_builddir)/src/lib/libeet.la
> >
> > Hence when I call objdump -p on my eet binary, i get:
> >
> >   NEEDED      libeet.so.1
> >   NEEDED      libz.so.1
> >   NEEDED      libjpeg.so.62
> >
> > But a friend told me that the eet binary should not have libz and
> > libjpeg, only libeet.
>
> On many modern systems it is not necessary to link against indirect
> dependencies.
>
> > 1) Is my friend right ?
>
> Partly.
>
> > 2) If he is right, what should I do to remove those "dependencies" ?
> > (flag to pass in a variable in my Makefile.am, or something like that)
>
> You can pass -Wl,--as-needed when the linker is the GNU binutils one.
> But beware that it may break things with some compilers (notably C++
> ones), with some apps that do dlopen and expect dependencies to be
present, and did not work right in some older versions of ld.

Do you have an idea if:

 * it works on Windows (mingw binutils) ?
 * from which version of ld it is safe to use that flag ?

I tried and with my binutils (linux for now), it works  (at least objdump 
does not report other dependencies, i've not tried yet the program)

> > eet_LDADD = $(top_builddir)/src/lib/libeet.la
> > eet_DEPENDENCIES = $(top_builddir)/src/lib/libeet.la
>
> The last line is not needed, automake can infer that from the one above.

Indeed :) I learn autotools things every days :) Now I have to clean all 
our libs and our main programs...

thank you very much

Vincent Torri