Re: Linking error on Ubuntu

[Kjell Ahlstedt <kjell ahlstedt bredband net>]

2011-10-18 15:56, Stefano Facchini skrev:
> Hi,
> could anyone using Ubuntu 11.10 have a look at bug 870662
> (https://bugs.launchpad.net/ubuntu/+source/gtkmm3.0/+bug/870662) and
> tell me if the same error is obtained?
Yes.
> Basically, it seems that I cannot link against gtkmm-3.0 and
> poppler-glib at the same time.
Actually, you cannot compile.

Look at the output from the following commands:
  pkg-config --cflags gtkmm-3.0
  pkg-config --cflags poppler-glib
  pkg-config --cflags gtkmm-3.0 poppler-glib

The interesting parts are:
  gtkmm-3.0: -I/usr/include/gtk-3.0
  poppler-glib: -I/usr/include/gtk-2.0
  gtkmm-3.0 poppler-glib: -I/usr/include/gtk-2.0 ... -I/usr/include/gtk-3.0

/usr/include/gdkmm-3.0/gdkmm/rgba.h contains
  #include <gdk/gdk.h>
which will include gdk/gdk.h from gtk-2.0, but rgba.h requires the file 
in gtk-3.0.

It's not possible to combine gtk-2.0 and gtk-3.0 in the same program.

You write in the Ubuntu bug:
1. The same test program compiles just fine with gtkmm-2.4.
    Understandable. gtk-3.0 is not included.

2. The equivalent C program linked against gtk+-3.0 also compiles fine.
    I guess that no header files are included from gtk-3.0, and that 
it's not detected by your extremely simple test program. Have you tried 
to compile a program that calls a function which exists only in gtk-3.0?

3. Moreover, I get no errors with other distributions I tried 
(Archlinux, openSUSE 12.01), even with gtkmm-3.0
    Don't know why. I don't know anything about poppler. I installed it 
only to be able to run your test case. Is there a newer version that 
uses gtk-3.0? (I got version 0.16.7.) Is the dependency on gtk (or gdk) 
unnecessary?
Perhaps pkg-config (or its equivalents) in the other distributions make 
the C preprocessor search /usr/include/gtk-3.0 before 
/usr/include/gtk-2.0? Then gtkmm will be happy, but perhaps poppler 
won't, if you compile a more complicated program than your test case.