diff --git a/gdk/Makefile.am b/gdk/Makefile.am
index 80387ccdda..6c16c42a40 100644
--- a/gdk/Makefile.am
+++ b/gdk/Makefile.am
@@ -35,6 +35,7 @@ INCLUDES = 				\
 	-DG_LOG_DOMAIN=\"Gdk\"		\
 	-DGDK_COMPILATION		\
 	-I$(top_srcdir)			\
+	-I$(top_builddir)		\
 	-I$(top_builddir)/gdk		\
 	$(GTK_DEBUG_FLAGS)		\
 	$(GDK_DEP_CFLAGS)