Horton

Re: PL_stashcache, or, what's our minimum Perl version?

Tom Lane <tgl@sss.pgh.pa.us>

View thread View on postgr.es
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
Cc: Noah Misch <noah@leadboat.com>, Andrew Dunstan <andrew@dunslane.net>, pgsql-hackers@postgresql.org
Date: 2017-07-31T18:55:16Z
Lists: pgsql-hackers 
Peter Eisentraut <peter.eisentraut@2ndquadrant.com> writes:
> On 7/30/17 12:50, Tom Lane wrote:
>> The reason it does that seems to be that we use AC_CHECK_PROGS
>> rather than AC_PATH_PROGS for locating "prove".  I can see no
>> particular consistency to the decisions made in configure.in
>> about which to use:

> We use the "PATH" variants when we need a fully qualified name.  For
> example, at some point or another, we needed to substitute a fully
> qualified perl binary name into the headers of scripts.

> If there is no such requirement, then we should use the non-PATH variants.

Why?  That risks failures of various sorts, and you have not stated
any actual benefit of it.

In cases where people do things like sticking non-default Perl builds
into nonstandard places, failing to record the absolute path to the
program configure saw is both a documentation fail and a clear hazard
to build reproducibility.  I think that "you can change your PATH and
get a different Perl version without reconfiguring" is an anti-feature,
because it poses a very high risk of not actually working.

			regards, tom lane

Commits

  1. Adjust configure to insist on Perl version >= 5.8.3.

  2. Further improve consistency of configure's program searching.

  3. Doc: specify that the minimum supported version of Perl is 5.8.3.

  4. Record full paths of programs sought by "configure".

  5. Abandon the use of Perl's Safe.pm to enforce restrictions in plperl, as it is