${ext_srcdir}/vstring.h \
${ext_srcdir}/vstring.tcc \
${ext_srcdir}/vstring_fwd.h \
- ${ext_srcdir}/vstring_util.h
+ ${ext_srcdir}/vstring_util.h \
+ ${ext_compat_headers}
+ext_compat_headers = \
+ ${backward_srcdir}/hash_set \
+ ${backward_srcdir}/hash_map
tr1_srcdir = ${glibcxx_srcdir}/include/tr1
tr1_builddir = ./tr1