Index: src/tclx/ucbsrc/tclbasic.sed
--- src/tclx/ucbsrc/tclbasic.sed.orig
+++ src/tclx/ucbsrc/tclbasic.sed
@@ -1,4 +1,5 @@
 /(\*cmdPtr->proc)/a\
+#include "tclxtend.h"\
 \        /*\
 \         * Signal handling added for Extended Tcl.\
 \         */\
