Bump minimum Perl version to 5.14

The oldest vendor-shipped Perl in the buildfarm is 5.14.2, which is
the last version that Debian Wheezy shipped. That OS is EOL, but we
keep it running because there is no other convenient way to test certain
non-mainstream 32-bit platforms. There is no bugfix in the 5.14.2 release
that is required, and yet it's also not the latest minor release --
that would be 5.14.4. To clarify the situation, we have thus arranged the
buildfarm to test 5.14.0. That allows configure scripts and documentation
to state 5.14 without fine print.

The MSVC build didn't check the version, since our previous minimum 5.8.3
was considered too old to check for on Windows. We will need a check for
Windows sometime during the v16 cycle, but that could be rendered moot
by the impending Meson conversion, so it seems safe to just document
the requirement for now.

Reviewed by Tom Lane
Discussion: https://www.postgresql.org/message-id/20220902181553.ev4pgzhubhdkguuv@awork3.anarazel.de

config/perl.m4

@@ -11,11 +11,11 @@ if test "$PERL"; then
   pgac_perl_version=`$PERL -v 2>/dev/null | sed -n ['s/This is perl.*v[a-z ]*\([0-9]\.[0-9][0-9.]*\).*$/\1/p']`
   AC_MSG_NOTICE([using perl $pgac_perl_version])
   if echo "$pgac_perl_version" | sed ['s/[.a-z_]/ /g'] | \
-    $AWK '{ if ([$]1 == 5 && ([$]2 > 8 || ($[2] == 8 && [$]3 >= 3))) exit 1; else exit 0;}'
+    $AWK '{ if ([$]1 == 5 && ([$]2 >= 14)) exit 1; else exit 0;}'
   then
     AC_MSG_WARN([
 *** The installed version of Perl, $PERL, is too old to use with PostgreSQL.
-*** Perl version 5.8.3 or later is required, but this is $pgac_perl_version.])
+*** Perl version 5.14 or later is required, but this is $pgac_perl_version.])
     PERL=""
   fi
 fi

configure

@@ -10491,14 +10491,14 @@ if test "$PERL"; then
   { $as_echo "$as_me:${as_lineno-$LINENO}: using perl $pgac_perl_version" >&5
 $as_echo "$as_me: using perl $pgac_perl_version" >&6;}
   if echo "$pgac_perl_version" | sed 's/[.a-z_]/ /g' | \
-    $AWK '{ if ($1 == 5 && ($2 > 8 || ($2 == 8 && $3 >= 3))) exit 1; else exit 0;}'
+    $AWK '{ if ($1 == 5 && ($2 >= 14)) exit 1; else exit 0;}'
   then
     { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING:
 *** The installed version of Perl, $PERL, is too old to use with PostgreSQL.
-*** Perl version 5.8.3 or later is required, but this is $pgac_perl_version." >&5
+*** Perl version 5.14 or later is required, but this is $pgac_perl_version." >&5
 $as_echo "$as_me: WARNING:
 *** The installed version of Perl, $PERL, is too old to use with PostgreSQL.
-*** Perl version 5.8.3 or later is required, but this is $pgac_perl_version." >&2;}
+*** Perl version 5.14 or later is required, but this is $pgac_perl_version." >&2;}
     PERL=""
   fi
 fi

doc/src/sgml/install-windows.sgml

@@ -190,7 +190,7 @@ $ENV{MSBFLAGS}="/m";
       or Cygwin Perl will not work. It must also be present in the PATH.
       Binaries can be downloaded from
       <ulink url="https://www.activestate.com"></ulink>
-      (Note: version 5.8.3 or later is required,
+      (Note: version 5.14 or later is required,
       the free Standard Distribution is sufficient).
      </para></listitem>
     </varlistentry>

doc/src/sgml/installation.sgml

@@ -165,7 +165,7 @@ su - postgres
       <application>PL/Perl</application> you need a full
       <productname>Perl</productname> installation, including the
       <filename>libperl</filename> library and the header files.
-      The minimum required version is <productname>Perl</productname> 5.8.3.
+      The minimum required version is <productname>Perl</productname> 5.14.
       Since <application>PL/Perl</application> will be a shared
       library, the <indexterm><primary>libperl</primary></indexterm>
       <filename>libperl</filename> library must be a shared library
@@ -325,7 +325,7 @@ su - postgres
        <primary>perl</primary>
       </indexterm>
 
-      <application>Perl</application> 5.8.3 or later is needed to build from a Git checkout,
+      <application>Perl</application> 5.14 or later is needed to build from a Git checkout,
       or if you changed the input files for any of the build steps that
       use Perl scripts.  If building on Windows you will need
       <application>Perl</application> in any case.  <application>Perl</application> is

src/pl/plperl/plc_perlboot.pl

@@ -6,7 +6,6 @@
 use strict;
 use warnings;
 
-use 5.008001;
 use vars qw(%_SHARED $_TD);
 
 PostgreSQL::InServer::Util::bootstrap();

src/test/perl/PostgreSQL/Test/Cluster.pm

@@ -2780,7 +2780,7 @@ all values '' if not found. Does not differentiate between null and empty string
 for fields, no field is ever undef.
 
 The restart_lsn and confirmed_flush_lsn fields are returned verbatim, and also
-as a 2-list of [highword, lowword] integer. Since we rely on Perl 5.8.8 we can't
+as a 2-list of [highword, lowword] integer. Since we rely on Perl 5.14 we can't
 "use bigint", it's from 5.20, and we can't assume we have Math::Bigint from CPAN
 either.
 

src/test/perl/README

@@ -78,10 +78,6 @@ Each test script should end with:
 
 	done_testing();
 
-Test::More::like entails use of the qr// operator.  Avoid Perl 5.8.8 bug
-#39185 by not using the "$" regular expression metacharacter in qr// when also
-using the "/m" modifier.  Instead of "$", use "\n" or "(?=\n|\z)".
-
 Test::Builder::Level controls how far up in the call stack a test will look
 at when reporting a failure.  This should be incremented by any subroutine
 which directly or indirectly calls test routines from Test::More, such as
@@ -103,7 +99,7 @@ Portability
 -----------
 
 Avoid using any bleeding-edge Perl features.  We have buildfarm animals
-running Perl versions as old as 5.8.3, so your tests will be expected
+running Perl versions as old as 5.14, so your tests will be expected
 to pass on that.
 
 Also, do not use any non-core Perl modules except IPC::Run.  Or, if you
@@ -116,8 +112,8 @@ One way to test for compatibility with old Perl versions is to use
 perlbrew; see http://perlbrew.pl .  After installing that, do
 
     export PERLBREW_CONFIGURE_FLAGS='-de -Duseshrplib'
-    perlbrew --force install 5.8.3
-    perlbrew use 5.8.3
+    perlbrew --force install 5.14.0
+    perlbrew use 5.14.0
     perlbrew install-cpanm
     cpanm install Test::Simple@0.98
     cpanm install IPC::Run@0.79

src/tools/msvc/gendef.pl

@@ -3,7 +3,6 @@
 
 use strict;
 use warnings;
-use 5.8.0;
 use List::Util qw(max);
 
 my @def;

src/tools/pgindent/pgindent

@@ -4,7 +4,6 @@
 
 use strict;
 use warnings;
-use 5.008001;
 
 use Cwd qw(abs_path getcwd);
 use File::Find;