diff --git a/doc/reference/cogl-2.0-experimental/Makefile.am b/doc/reference/cogl-2.0-experimental/Makefile.am
index 0e9cf2ef6..3e8bc1e6b 100644
--- a/doc/reference/cogl-2.0-experimental/Makefile.am
+++ b/doc/reference/cogl-2.0-experimental/Makefile.am
@@ -47,8 +47,7 @@ FIXXREF_OPTIONS=\
 HFILE_GLOB=\
 	$(top_srcdir)/cogl/*.h \
 	$(top_builddir)/cogl/*.h \
-	$(top_srcdir)/cogl/winsys/*.h \
-	$(top_builddir)/cogl/winsys/*.h
+	$(top_srcdir)/cogl/winsys/*.h
 CFILE_GLOB=$(top_srcdir)/cogl/*.c
 
 # Header files to ignore when scanning.