Unescaped left brace in regex is deprecated here

背景

            编译indent-2.2.12,调用指令bootstrap，出错提示：

#### running automake
Unescaped left brace in regex is deprecated here (and will be fatal in Perl 5.30), passed through in regex; marked by <– HERE in m//${ <– HERE ([^ /t=:+{}]+)}/ at /usr/local/bin/automake line 3930.
automake (GNU automake) 1.14.1
Copyright (C) 2013 Free Software Foundation, Inc.
License GPLv2+: GNU GPL version 2 or later <http://gnu.org/licenses/gpl-2.0.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Written by Tom Tromey <tromey@redhat.com>
       and Alexandre Duret-Lutz <adl@gnu.org>.
Unescaped left brace in regex is deprecated here (and will be fatal in Perl 5.30), passed through in regex; marked by <– HERE in m//${ <– HERE ([^ /t=:+{}]+)}/ at /usr/local/bin/automake line 3930.
rm: cannot remove ‘README’: No such file or directory

解决

            将automake 1.14.1版本升级到1.16.1