AC_ARG_ENABLE([umem],
[AS_HELP_STRING([--enable-umem],
[Enable linking with libumem @<:@default=off@:>@])],
- [ac_enable_umem="$enableval"],
- [ac_enable_umem="no"])
+ [ac_enable_umem="$enableval"],[
+ case "$target_os" in
+ *solaris*)
+ ac_enable_umem="yes"
+ ;;
+ *)
+ ac_enable_umem="no"
+ ;;
+ esac
+ ])
AC_ARG_ENABLE([tcmalloc],
[AS_HELP_STRING([--enable-tcmalloc],