Handle getconf returning "undefined".

* m4/libtool.m4: Check for "undefined" from `getconf`.

diff --git a/m4/libtool.m4 b/m4/libtool.m4
index 75bfdb48ada183d6bf96d934688d97b8e0cb32b5..a8ecbc371a1351a458132e1b4a86cb548c3cc220 100644 (file)
--- a/m4/libtool.m4
+++ b/m4/libtool.m4
@@ -1692,7 +1692,8 @@ AC_CACHE_VAL([lt_cv_sys_max_cmd_len], [dnl
     ;;
   *)
     lt_cv_sys_max_cmd_len=`(getconf ARG_MAX) 2> /dev/null`
-    if test -n "$lt_cv_sys_max_cmd_len"; then
+    if test -n "$lt_cv_sys_max_cmd_len" && \
+       test undefined != "$lt_cv_sys_max_cmd_len"; then
       lt_cv_sys_max_cmd_len=`expr $lt_cv_sys_max_cmd_len \/ 4`
       lt_cv_sys_max_cmd_len=`expr $lt_cv_sys_max_cmd_len \* 3`
     else