2010/9/14 Olivier Andrieu <oandrieu@gmail.com>

Hi !

On Tue, Sep 14, 2010 at 11:50, Johan Mazel <johan.mazel@gmail.com> wrote:
> Hi
> I'm trying to use Cairo and GTK.
> As a first step, I tried to compile and understand the cube example gi= ven at
> this address: http://webcvs.cairographics.org/cairo-ocaml/test/.

btw the current code is in the git repository, not CVS:
http= ://cgit.freedesktop.org/cair gito-ocaml/

I fig= ured from the link http://webcvs.cairographics.org/cairo-ocaml/ that the project might ha= ve been moved somewhere else but since your personnal webpage was still lin= king to FreeDesktop and since I was lazy, I didn't search in the page <= a href=3D"http://cgit.freedesktop.org/">http://cgit.freedesktop.org/.

=A0

> I use this line for the native compilation: ocamlopt -I +lablgtk2 -I += cairo
> lablgtk.cmxa cairo.cmxa cairo_lablgtk.cmxa cube.ml -o cube.
>
> The first problem is that the bytecode compilation do not work:
> ocamlc -I +lablgtk2 -I +cairo lablgtk.cma cairo.cma cairo_lablgtk.cma<= br> > cube.ml -o cube
> File "cube.ml&qu= ot;, line 1, characters 0-1:
> Error: Error on dynamically loaded library:
> /usr/lib/ocaml/stublibs/dllmlcairo.so:
> /usr/lib/ocaml/stublibs/dllmlcairo.so: undefined symbol: caml_ba_byte_= size

This looks like some binary incompatibility between ocaml and your cairo-ocaml binary.
caml_ba_byte_size is a symbol from the Bigarray library that got
renamed at some point.

Did you compile cairo-ocaml yourself ? If no, you have to ensure that
you're using it with the same OCaml version that compiled it.

> I however tried to run the native executable generated but I get the > following error:
> (process:6496): GLib-GObject-WARNING **: invalid (NULL) pointer instan= ce
> (process:6496): GLib-GObject-CRITICAL **: g_signal_connect_data: asser= tion
> `G_TYPE_CHECK_INSTANCE (instance)' failed
> (process:6496): Gdk-CRITICAL **: gdk_pango_context_get_for_screen: ass= ertion
> `GDK_IS_SCREEN (screen)' failed
> (process:6496): Pango-CRITICAL **: pango_context_set_font_description:=
> assertion `context !=3D NULL' failed
> (process:6496): Pango-CRITICAL **: pango_context_set_base_dir: asserti= on
> `context !=3D NULL' failed
> (process:6496): Pango-CRITICAL **: pango_context_set_language: asserti= on
> `context !=3D NULL' failed
> (process:6496): Pango-CRITICAL **: pango_layout_new: assertion `contex= t !=3D
> NULL' failed
> (process:6496): Pango-CRITICAL **: pango_layout_set_text: assertion `l= ayout
> !=3D NULL' failed
> (process:6496): Pango-CRITICAL **: pango_layout_get_pixel_extents: ass= ertion
> `PANGO_IS_LAYOUT (layout)' failed
> (process:6496): Pango-CRITICAL **: pango_layout_set_text: assertion `l= ayout
> !=3D NULL' failed
> (process:6496): Pango-CRITICAL **: pango_layout_get_pixel_extents: ass= ertion
> `PANGO_IS_LAYOUT (layout)' failed
> (process:6496): GLib-GObject-CRITICAL **: g_object_unref: assertion > `G_IS_OBJECT (object)' failed
> (process:6496): Gtk-WARNING **: Screen for GtkWindow not set; you must=
> always set
> a screen for a GtkWindow before using the window
> (process:6496): Gdk-CRITICAL **: gdk_pango_context_get_for_screen: ass= ertion
> `GDK_IS_SCREEN (screen)' failed
> (process:6496): Pango-CRITICAL **: pango_context_set_font_description:=
> assertion `context !=3D NULL' failed
> (process:6496): Pango-CRITICAL **: pango_context_set_base_dir: asserti= on
> `context !=3D NULL' failed
> (process:6496): Pango-CRITICAL **: pango_context_set_language: asserti= on
> `context !=3D NULL' failed
> (process:6496): Pango-CRITICAL **: pango_layout_new: assertion `contex= t !=3D
> NULL' failed
> (process:6496): GLib-GObject-CRITICAL **: g_object_unref: assertion > `G_IS_OBJECT (object)' failed
> (process:6496): Gdk-CRITICAL **: gdk_pango_context_get_for_screen: ass= ertion
> `GDK_IS_SCREEN (screen)' failed
> (process:6496): Pango-CRITICAL **: pango_context_set_font_description:=
> assertion `context !=3D NULL' failed
> (process:6496): Pango-CRITICAL **: pango_context_set_base_dir: asserti= on
> `context !=3D NULL' failed
> (process:6496): Pango-CRITICAL **: pango_context_set_language: asserti= on
> `context !=3D NULL' failed
> (process:6496): Pango-CRITICAL **: pango_layout_new: assertion `contex= t !=3D
> NULL' failed
> (process:6496): Pango-CRITICAL **: pango_layout_set_text: assertion `l= ayout
> !=3D NULL' failed
> (process:6496): Pango-CRITICAL **: pango_layout_set_alignment: asserti= on
> `layout !=3D NULL' failed
> (process:6496): Pango-CRITICAL **: pango_layout_set_ellipsize: asserti= on
> `PANGO_IS_LAYOUT (layout)' failed
> (process:6496): Pango-CRITICAL **: pango_layout_set_single_paragraph_m= ode:
> assertion `PANGO_IS_LAYOUT (layout)' failed
> (process:6496): Pango-CRITICAL **: pango_layout_set_width: assertion `= layout
> !=3D NULL' failed
> (process:6496): Pango-CRITICAL **: pango_layout_get_extents: assertion=
> `layout !=3D NULL' failed
> (process:6496): Gdk-CRITICAL **: gdk_screen_get_default_colormap: asse= rtion
> `GDK_IS_SCREEN (screen)' failed
> (process:6496): Gdk-CRITICAL **: gdk_colormap_get_visual: assertion > `GDK_IS_COLORMAP (colormap)' failed
> (process:6496): Gdk-CRITICAL **: gdk_screen_get_default_colormap: asse= rtion
> `GDK_IS_SCREEN (screen)' failed
> (process:6496): Gdk-CRITICAL **: gdk_screen_get_root_window: assertion=
> `GDK_IS_SCREEN (screen)' failed
> (process:6496): Gdk-CRITICAL **: gdk_screen_get_root_window: assertion=
> `GDK_IS_SCREEN (screen)' failed
> (process:6496): Gdk-CRITICAL **: gdk_window_new: assertion `GDK_IS_WIN= DOW
> (parent)' failed
> Erreur de segmentation

probably simply the gtk initialization missing. Add gtkInit.cmx= before
cube.ml while linking.

--
=A0Olivier

That wa= s the problem, thanks for the fast answer.

Regards.
Johan Mazel