Comment 1 for bug 1753068

So I tried to build virt-viewer from source. However, the source package in raspbian archives required newer spice-client-glib/gtk than that available in the archives:

Requested 'spice-client-gtk-3.0 >= 0.33' but version of spice-client-gtk-3.0 is 0.32
Requested 'spice-client-glib-2.0 >= 0.33' but version of spice-client-glib-2.0 is 0.32

The source package of spice-gtk in raspbian is version 0.32, not 0.33, so I tried to build from git ( https://anonscm.debian.org/git/collab-maint/spice-gtk.git ) which had 0.33.
This, however, brought me to the real issue:
(full log in attachment)

In file included from /usr/include/glib-2.0/gobject/gobject.h:24:0,
                 from /usr/include/glib-2.0/gobject/gbinding.h:29,
                 from /usr/include/glib-2.0/glib-object.h:23,
                 from spice-client.h:23,
                 from spice-file-transfer-task-priv.h:25,
                 from spice-file-transfer-task.c:20:
spice-file-transfer-task.c: In function ‘spice_file_transfer_task_get_property’:
/usr/include/glib-2.0/gobject/gtype.h:2207:6: error: cast increases required alignment of target type [-Werror=cast-align]
     ((ct*) g_type_check_instance_cast ((GTypeInstance*) ip, gt))
      ^

So this seems like a real bug in spice-gtk 0.34 or glib-2.0, or I am compiling the wrong code not patched for armhf. Either way, more research is required.