The AC_HELP_STRING has been made obsolete since Autoconf 2.58 somewhere
in 2003. The new AS_HELP_STRING macro has been since recommended to be
used and should be today supported on most systems out there. The phpize
script for PHP 7.2+ requires Autoconf 2.59 and PHP requires 2.64.
This patch has been made with the help of the autoupdate script.
Autoconf changelog:
- http://git.savannah.gnu.org/cgit/autoconf.git/tree/ChangeLog.3
GitHub's file finder filters out "build/" directories, among others, which can make it difficult to quickly access these files. Also, the "build/" directory doesn't provide much value here, since it only contains "autotools/".