+######################################################################## lopsub
+STASH_FLAGS
+LIB_ARG_WITH([lopsub], [-llopsub])
+HAVE_LOPSUB=yes
+AC_CHECK_HEADER(lopsub.h, [], [HAVE_LOPSUB=no])
+AC_CHECK_LIB([lopsub], [lls_merge], [], [HAVE_LOPSUB=yes])
+if test $HAVE_LOPSUB = no; then AC_MSG_ERROR([
+ The lopsub library is required to build this software, but
+ the above checks indicate it is not installed on your system.
+ Run the following command to download a copy.
+ git clone git://git.tuebingen.mpg.de/lopsub.git
+ Install the library, then run this configure script again.
+])
+fi
+LIB_SUBST_FLAGS([lopsub])
+UNSTASH_FLAGS