Re: plperl: update ppport.h and fix configure version check

Daniel Gustafsson <daniel(at)yesql(dot)se> writes:

>> On 5 Oct 2021, at 05:12, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>
>> In short: (a) we're not testing against anything older than 5.8.3
>> and (b) it seems quite unlikely that anybody cares about 5.8.x anyway.
>> So if we want to mess with this, maybe we should set the cutoff
>> to 5.8.3 not 5.8.1.
>
> Not being able to test against older versions in the builfarm seems like a
> pretty compelling reason to set 5.8.3 as the required version.

Looking at the list of Perl versions shipped with various OSes
(https://www.cpan.org/ports/binaries.html) bumping the minimum
requirement from 5.8.1 to 5.8.3 will affect the following OS versions,
which shipped 5.8.1 or 5.8.2:

AIX: 5.3, 6.1
Fedora: 1 (Yarrow)
macOS: 10.3 (Panther)
Redhat: 2.1
Slackware: 9.0, 9.1
OpenSUSE: 8.2

The only one of these that I can imagine we might possibly care about is
AIX, but I don't know what versions we claim to support or people
actually run PostgreSQL on (and want to upgrade to 15). The docs at
https://www.postgresql.org/docs/current/installation-platform-notes.html
just say that "AIX versions before about 6.1 […] are not recommended".

For reference, 6.1 was released on 2007-11-09 and EOL on 2017-04-30, and
7.1 was released on 2010-09-10 and is supported until 2023-04-30.

- ilmari