diff --git a/src/glx/Makefile.am b/src/glx/Makefile.am
index aa3d8edf033..40e6b609dbf 100644
--- a/src/glx/Makefile.am
+++ b/src/glx/Makefile.am
@@ -37,6 +37,8 @@ AM_CFLAGS = \
 	-I$(top_srcdir)/include/GL/internal \
 	-I$(top_srcdir)/src/mapi \
 	-I$(top_srcdir)/src/mapi/glapi \
+	-I$(top_builddir)/src/mapi \
+	-I$(top_builddir)/src/mapi/glapi \
 	$(SHARED_GLAPI_CFLAGS) \
 	$(EXTRA_DEFINES_XF86VIDMODE) \
 	-D_REENTRANT \