diff --git a/configure.ac b/configure.ac
index 23ea18d..35abfbf 100644
--- a/configure.ac
+++ b/configure.ac
@@ -63,9 +63,7 @@ XORG_DRIVER_CHECK_EXT(XFreeXDGA, xf86dgaproto)
 PKG_CHECK_MODULES(XORG, [xorg-server >= 1.0.99.901] xproto fontsproto $REQUIRED_MODULES)
 
 CFLAGS="$CFLAGS $XORG_CFLAGS "' -I$(top_srcdir)/src'
-INCLUDES='-I$(top_srcdir)/src'
 AC_SUBST([CFLAGS])
-AC_SUBST([INCLUDES])
 
 # Checks for libraries.