Index: Makefile.am
===================================================================
--- Makefile.am	(revision 33159)
+++ Makefile.am	(working copy)
@@ -143,7 +143,7 @@
 	xyz-pl \
 	yuv-pix
 
-AM_CPPFLAGS = ${TCL_CPPFLAGS}
+AM_CPPFLAGS = ${TCL_CPPFLAGS} ${TK_CPPFLAGS}
 
 noinst_PROGRAMS = \
 	roots_example \