AM_PATH_GTK_3_0([3.4], [], [], [gthread]) results in calling
"pkg-config --atleast-version 3.4 gtk+-3.0 gthread-2.0".
With pkg-config 0.28, that test fails, because the version of
gthread-2.0 is smaller than 3.4. This appears to be a behaviour
change since 0.26, but matches what the documentation said in 0.26.
Bug: https://bugzilla.gnome.org/show_bug.cgi?id=641638
Bug-Debian: https://bugs.debian.org/756476
Reviewed-by: Matthias Clasen <mclasen@redhat.com>
Now that a single shared object can contain multiple backends we also
need to provide a simple way for third party code to verify that the
copy of GDK they are linking to supports their backend.
The simplest way to verify is an m4 macro, GTK_CHECK_BACKEND(), shipped
with the gtk+ m4 macros.
The usage is pretty basic:
GTK_CHECK_BACKEND([x11], [gtk_has_x11=yes], [gtk_has_x11=no])
AM_CONDITIONAL(BUILD_X11_CODE, test "x$gtk_has_x11" = "xno")
https://bugzilla.gnome.org/show_bug.cgi?id=642479