Don't encode the current timestamp.

This affects the output of `perl -V`, specifically the message "Compiled
at [...]".

The 'cf_time' and 'cf_by' values show up in 'config.h' and
in 'Config_heavy.pl'.

Use the output of 'uname -s' instead of 'uname -a' to avoid recording
the kernel version ('uname -o' leads to directory names like
'x86_64-gnulinux' instead of 'x86_64-linux', which might cause breakage
down the road.)

diff --git a/perl.c b/perl.c
index 228a0d8..ed38313 100644
--- a/perl.c
+++ b/perl.c
@@ -1825,6 +1825,7 @@ S_Internals_V(pTHX_ CV *cv)
     PUSHs(Perl_newSVpvn_flags(aTHX_ non_bincompat_options,
 			      sizeof(non_bincompat_options) - 1, SVs_TEMP));
 
+#define PERL_BUILD_DATE "Jan  1 1970 00:00:00"
 #ifndef PERL_BUILD_DATE
 #  ifdef __DATE__
 #    ifdef __TIME__

--- a/Configure	1970-01-01 01:00:00.000000000 +0100
+++ b/Configure	2016-10-01 14:47:20.017319739 +0200
@@ -3276,7 +3276,7 @@ $eunicefix tr
 : Try to determine whether config.sh was made on this system
 case "$config_sh" in
 '')
-myuname=`$uname -a 2>/dev/null`
+myuname=`$uname -s 2>/dev/null`
 $test -z "$myuname" && myuname=`hostname 2>/dev/null`
 # Downcase everything to avoid ambiguity.
 # Remove slashes and single quotes so we can use parts of this in
@@ -3845,10 +3845,10 @@
 . ./posthint.sh
 
 : who configured the system
-cf_time=`LC_ALL=C; LANGUAGE=C; export LC_ALL; export LANGUAGE; $date 2>&1`
+cf_time="1970-01-01"
 case "$cf_by" in
 "")
-	cf_by=`(logname) 2>/dev/null`
+	cf_by="guix"
 	case "$cf_by" in
 	"")
 		cf_by=`(whoami) 2>/dev/null`
d331f964415bcf9628fcc27968'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/guix/log/?id=88f294cc1442ead331f964415bcf9628fcc27968'>root</a>/<a href='/guix/log/HACKING?id=88f294cc1442ead331f964415bcf9628fcc27968'>HACKING</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/HACKING?id=88f294cc1442ead331f964415bcf9628fcc27968&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2020-10-23 12:57:20 -0400'>2020-10-23</span></td><td><a href='/guix/commit/HACKING?id=73faee9fb25465f1b236f5f94e1052145655736f'>doc: Fix typo in HACKING.</a><span class='msg-avail'>...<span class='msg-tooltip'>* HACKING (Contributing): s/informations/information/.
</span></span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2020-01-09 23:33:04 +0100'>2020-01-09</span></td><td><a href='/guix/commit/HACKING?id=2d315cd428484537e763d7f7c676dc5fff7995f6'>doc: Move "Commit Access" section from 'HACKING' to the manual.</a><span class='msg-avail'>...<span class='msg-tooltip'>* HACKING (Commit Access): Remove.
(Contributing): Update URL of the manual.
* doc/contributing.texi (Commit Access): New section.
(Submitting Patches): Add cross reference.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2020-01-09 23:33:04 +0100'>2020-01-09</span></td><td><a href='/guix/commit/HACKING?id=a7bde77d247ed0765f5378779d67b4668c5d7648'>doc: Add "Tracking Bugs and Patches" section.</a><span class='msg-avail'>...<span class='msg-tooltip'>* doc/contributing.texi (Tracking Bugs and Patches): New section.
(Submitting Patches): Refer to it.
* doc/guix.texi: Update copyright line.
* HACKING (Using emacs-debbugs): Remove.
</span></span></td><td>Ludovic Courtès</td></tr>