diff --git a/configure.ac b/configure.ac
index 816898854..dcb7574d6 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1015,7 +1015,7 @@ AC_MSG_CHECKING([whether to use statfs or statvfs])
 AS_IF([test x$ac_cv_func_statfs = xyes && test x$ac_cv_func_statvfs = xyes],
    [
    # on solaris and irix, statfs doesn't even have the f_bavail field
-   AS_IF([test x$ac_cv_member_struct_statfs_f_bavail = xyes],
+   AS_IF([test x$ac_cv_member_struct_statfs_f_bavail = xno],
       [ac_cv_func_statfs=no],
    # else, at least on linux, statfs is the actual syscall
       [ac_cv_func_statvfs=no])