I tried to compile the latest Ardour-2.x today from svn and it ended like so:
In file included from libs/glibmm2/glibmm/containerhandle_shared.h:32:0,
from libs/glibmm2/glibmm/arrayhandle.h:24,
from libs/glibmm2/glibmm/miscutils.h:24,
from libs/pbd/basename.cc:21:
/usr/include/glib-2.0/glib/gmem.h:28:2: error: #error "Only can be included directly."
In file included from libs/glibmm2/glibmm/ustring.h:24:0,
from libs/glibmm2/glibmm/containerhandle_shared.h:34,
from libs/glibmm2/glibmm/arrayhandle.h:24,
from libs/glibmm2/glibmm/miscutils.h:24,
from libs/pbd/basename.cc:21:
/usr/include/glib-2.0/glib/gmacros.h:32:2: error: #error "Only can be included directly."
In file included from libs/glibmm2/glibmm/ustring.h:25:0,
from libs/glibmm2/glibmm/containerhandle_shared.h:34,
from libs/glibmm2/glibmm/arrayhandle.h:24,
from libs/glibmm2/glibmm/miscutils.h:24,
from libs/pbd/basename.cc:21:
/usr/include/glib-2.0/glib/gunicode.h:23:2: error: #error "Only can be included directly."
In file included from libs/glibmm2/glibmm/unicode.h:27:0,
from libs/glibmm2/glibmm/ustring.h:26,
from libs/glibmm2/glibmm/containerhandle_shared.h:34,
from libs/glibmm2/glibmm/arrayhandle.h:24,
from libs/glibmm2/glibmm/miscutils.h:24,
from libs/pbd/basename.cc:21:
/usr/include/glib-2.0/glib/gmacros.h:32:2: error: #error "Only can be included directly."
In file included from libs/glibmm2/glibmm/unicode.h:28:0,
from libs/glibmm2/glibmm/ustring.h:26,
from libs/glibmm2/glibmm/containerhandle_shared.h:34,
from libs/glibmm2/glibmm/arrayhandle.h:24,
from libs/glibmm2/glibmm/miscutils.h:24,
from libs/pbd/basename.cc:21:
/usr/include/glib-2.0/glib/gstrfuncs.h:28:2: error: #error "Only can be included directly."
In file included from libs/glibmm2/glibmm/unicode.h:29:0,
from libs/glibmm2/glibmm/ustring.h:26,
from libs/glibmm2/glibmm/containerhandle_shared.h:34,
from libs/glibmm2/glibmm/arrayhandle.h:24,
from libs/glibmm2/glibmm/miscutils.h:24,
from libs/pbd/basename.cc:21:
/usr/include/glib-2.0/glib/gunicode.h:23:2: error: #error "Only can be included directly."
In file included from libs/glibmm2/glibmm/debug.h:24:0,
from libs/glibmm2/glibmm/containerhandle_shared.h:36,
from libs/glibmm2/glibmm/arrayhandle.h:24,
from libs/glibmm2/glibmm/miscutils.h:24,
from libs/pbd/basename.cc:21:
/usr/include/glib-2.0/glib/gmacros.h:32:2: error: #error "Only can be included directly."
scons: *** [libs/pbd/basename.os] Error 1
scons: building terminated because of errors.