diff --git a/configure.ac b/configure.ac
index cf19d36c5e..d888239182 100644
--- a/configure.ac
+++ b/configure.ac
@@ -990,6 +990,8 @@ AM_CONDITIONAL(USE_DIRECTSOUND, false)
 AM_CONDITIONAL(USE_DV1394, false)
 AM_CONDITIONAL(USE_FLAC, false)
 AM_CONDITIONAL(USE_GDK_PIXBUF, false)
+AM_CONDITIONAL(USE_GTK3, false)
+AM_CONDITIONAL(USE_GTK3_GL, false)
 AM_CONDITIONAL(USE_JACK, false)
 AM_CONDITIONAL(USE_JPEG, false)
 AM_CONDITIONAL(USE_LAME, false)