+AC_PROG_LEX
+AC_PROG_YACC
+
+AC_CHECK_PROGS(AR, ar)
+
+dnl Look for an external 'cpp' program which can run on a file with any
+dnl extension. The normal CPP can only run on files with a '.c'
+dnl extension, therefore we prefer to use /usr/bin/cpp if it exists.
+AC_PATH_PROG([EXTCPP], [cpp], [no])
+if test "x$EXTCPP" = "xno"; then
+ AC_MSG_FAILURE([Cannot find a working 'cpp' (C preprocessor) program])
+fi
+AC_DEFINE_UNQUOTED([EXTCPP], ["$EXTCPP"],
+ [The C preprocessor command (may include command line options).])
+
+MINGW_EXTRA_LDFLAGS=
+case "$host" in
+ *-*-mingw*)
+ MINGW_EXTRA_LDFLAGS="-no-undefined"
+ ;;
+esac
+AC_SUBST(MINGW_EXTRA_LDFLAGS)
+
+AC_CHECK_HEADERS([arpa/inet.h sys/param.h])
+AC_CHECK_FUNCS([ntohl htonl ntohs htons])