+dnl enabled external libFirm plugins
+dnl -------------
+AC_MSG_CHECKING([for external libfirm plugins])
+AC_ARG_WITH(plugins,
+[ --with-plugins=list include external libfirm plugins list (space separated)],
+[
+ plugin_subdirs=$withval
+ plugin_files=
+ for i in $withval ; do
+ plugin_files="$i/Makefile $plugin_files"
+ done
+ ac_output_file="$ac_output_file $plugin_files"
+],
+[
+ plugin_files=
+ plugin_subdirs=
+])
+AC_SUBST(plugin_subdirs)
+if test "$plugin_subdirs" == ""; then
+ AC_MSG_RESULT([disabled])
+else
+ AC_MSG_RESULT([$plugin_subdirs])
+fi
+
+dnl check for additional include dirs
+AC_ARG_WITH(includedir, [ --with-includedir=add colon seperated list of directories to include search path],
+ CPPFLAGS=$CPPFLAGS" -I"`echo $withval|sed 's;\:; -I;g'`)
+
+dnl check for additional library dirs
+AC_ARG_WITH(libdir, [ --with-libdir=add colon seperated list of directories to linker search path],
+ LDFLAGS=$LDFLAGS" -L"`echo $withval|sed 's;\:; -L;g'`)
+
+dnl check for libxml2 library installation dir
+AC_ARG_WITH(libxml2, [ --with-libxml2=prefix installation prefix of libxml2 (IPD: --with-libxml2=/usr/public/libxml2)],
+ LDFLAGS=$LDFLAGS" -L"$withval"/lib";
+ CPPFLAGS=$CPPFLAGS" -I"$withval"/include/libxml2")
+