--- libsrc/csg/Makefile.in.orig	2014-10-06 11:04:37 UTC
+++ libsrc/csg/Makefile.in
@@ -285,7 +285,7 @@ meshsurf.hpp solid.hpp triapprox.hpp csg
 polyhedra.hpp specpoin.hpp csg.hpp explicitcurve2d.hpp identify.hpp   \
 revolution.hpp spline3d.hpp vscsg.hpp
 
-AM_CPPFLAGS = -I$(top_srcdir)/libsrc/include  $(TCL_INCLUDES)
+AM_CPPFLAGS = -I$(top_srcdir)/libsrc/include  $(TCL_INCLUDES) $(TK_INCLUDES)
 METASOURCES = AUTO
 lib_LTLIBRARIES = libcsg.la $(am__append_1)
 libcsg_la_SOURCES = algprim.cpp brick.cpp   \