diff --git a/clutter/cogl/cogl/Makefile.am b/clutter/cogl/cogl/Makefile.am
index 2e75cb261..3435fafc7 100644
--- a/clutter/cogl/cogl/Makefile.am
+++ b/clutter/cogl/cogl/Makefile.am
@@ -39,6 +39,7 @@ AM_CPPFLAGS = \
 	-DG_DISABLE_DEPRECATED			\
 	-DG_LOG_DOMAIN=\"Cogl-$(COGL_WINSYS)\" 	\
 	-DCLUTTER_COMPILATION			\
+	-DCOGL_ENABLE_EXPERIMENTAL_API		\
 	$(COGL_DEBUG_CFLAGS) 			\
 	$(CLUTTER_DEBUG_CFLAGS) 		\
 	$(NULL)
diff --git a/clutter/glx/Makefile.am b/clutter/glx/Makefile.am
index f0206b318..b40316144 100644
--- a/clutter/glx/Makefile.am
+++ b/clutter/glx/Makefile.am
@@ -12,6 +12,7 @@ INCLUDES = \
 	-I$(top_builddir)/clutter \
 	-I$(top_builddir)/clutter/cogl \
         -DCLUTTER_COMPILATION \
+	-DCOGL_ENABLE_EXPERIMENTAL_API \
 	$(CLUTTER_CFLAGS) \
 	$(CLUTTER_DEBUG_CFLAGS) \
 	$(MAINTAINER_CFLAGS)
diff --git a/clutter/x11/Makefile.am b/clutter/x11/Makefile.am
index e626ca663..6e227bb71 100644
--- a/clutter/x11/Makefile.am
+++ b/clutter/x11/Makefile.am
@@ -5,6 +5,7 @@ NULL =
 INCLUDES = \
 	-DG_LOG_DOMAIN=\"ClutterX11\"           \
         -DCLUTTER_COMPILATION                   \
+	-DCOGL_ENABLE_EXPERIMENTAL_API          \
 	-I$(top_srcdir)                         \
 	-I$(top_srcdir)/clutter 	        \
 	-I$(top_srcdir)/clutter/cogl 	        \