perl-net-dns-resolver-programmable used the undocumented and internal
method Net::DNS::rcodesbyname [0], and that interface is no longer
exposed.

This patch, copied from [1], makes the program check for the existence
of the method before trying to use it.

[0]
<https://rt.cpan.org/Public/Bug/Display.html?id=95901>

[1]
<https://rt.cpan.org/Public/Bug/Display.html?id=95901#txn-1575108>

diff --git a/lib/Net/DNS/Resolver/Programmable.pm b/lib/Net/DNS/Resolver/Programmable.pm
index 1af72ce..e09a2f0 100644
--- a/lib/Net/DNS/Resolver/Programmable.pm
+++ b/lib/Net/DNS/Resolver/Programmable.pm
@@ -203,8 +203,10 @@ sub send {
     if (defined(my $resolver_code = $self->{resolver_code})) {
         ($result, $aa, @answer_rrs) = $resolver_code->($domain, $rr_type, $class);
     }
-    
-    if (not defined($result) or defined($Net::DNS::rcodesbyname{$result})) {
+
+    if (not defined($result)
+         or defined($Net::DNS::Parameters::rcodebyname{$result})
+         or defined($Net::DNS::rcodesbyname{$result})) {
         # Valid RCODE, return a packet:
         
         $aa     = TRUE      if not defined($aa);
refs</a><a class='active' href='/guix/log/gnu/build/bootloader.scm'>log</a><a href='/guix/tree/gnu/build/bootloader.scm?id=0c518f974e64f23846ae51ea2c68b479202fdca9'>tree</a><a href='/guix/commit/gnu/build/bootloader.scm?id=0c518f974e64f23846ae51ea2c68b479202fdca9'>commit</a><a href='/guix/diff/gnu/build/bootloader.scm?id=0c518f974e64f23846ae51ea2c68b479202fdca9'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/gnu/build/bootloader.scm'>
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<div class='path'>path: <a href='/guix/log/?id=0c518f974e64f23846ae51ea2c68b479202fdca9'>root</a>/<a href='/guix/log/gnu?id=0c518f974e64f23846ae51ea2c68b479202fdca9'>gnu</a>/<a href='/guix/log/gnu/build?id=0c518f974e64f23846ae51ea2c68b479202fdca9'>build</a>/<a href='/guix/log/gnu/build/bootloader.scm?id=0c518f974e64f23846ae51ea2c68b479202fdca9'>bootloader.scm</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/gnu/build/bootloader.scm?id=0c518f974e64f23846ae51ea2c68b479202fdca9&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2022-06-24 10:21:06 +0200'>2022-06-24</span></td><td><a href='/guix/commit/gnu/build/bootloader.scm?id=62c86c8391ceb8953ca972498fd75ea9298b85ff'>image: Add support for 32bit UEFI.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/bootloader/grub.scm (grub-efi32-bootloader): New variable.
(install-grub-efi32): New variable.
* gnu/build/bootloader.scm (install-efi): Add a 'targets' keyword
argument.
(install-efi-loader): Likewise.
* gnu/build/image.scm (initialize-efi32-partition): New procedure.
* gnu/packages/bootloaders.scm (grub-efi32): New variable.
* gnu/system/image.scm (esp32-partition): New variable
(efi32-disk-image): New variable.
(efi32-raw-image-type): New variable.
(system-disk-image)[partition-image]: Set '#:grub-efi32' when
calling the partition initializer.

Signed-off-by: Mathieu Othacehe &lt;othacehe@gnu.org&gt;
</span></span></td><td>Denis 'GNUtoo' Carikli</td></tr>
<tr><td><span title='2021-11-12 13:26:52 +0000'>2021-11-12</span></td><td><a href='/guix/commit/gnu/build/bootloader.scm?id=fb3df2011692b2a6fea9f4fefd71dd788453fbae'>build: bootloader: Add GPT support.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/build/bootloader.scm (install-efi-loader): Add GPT support.
</span></span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2020-11-03 07:59:59 +0100'>2020-11-03</span></td><td><a href='/guix/commit/gnu/build/bootloader.scm?id=a38d861e571c952f78ca588b50bdcc4adcb0c88c'>system: reconfigure: Use the disk-installer if provided.</a><span class='msg-avail'>...<span class='msg-tooltip'>Fixes: &lt;https://issues.guix.gnu.org/44101&gt;.

* gnu/build/bootloader.scm (write-file-on-device): Pass 'no-fail flag instead
of 'no-create. Use a latin-1 transcoder.
* guix/scripts/system/reconfigure.scm (install-bootloader-program): Add a
"disk-installer" argument and use it as a fallback.
(install-bootloader): Adapt accordingly.
* gnu/tests/reconfigure.scm (run-install-bootloader-test): Ditto.
</span></span></td><td>Mathieu Othacehe</td></tr>
<tr><td><span title='2020-10-05 11:10:35 +0200'>2020-10-05</span></td><td><a href='/guix/commit/gnu/build/bootloader.scm?id=b97b423e3f61c80d5877dadc95b3f316cd61788f'>bootloader: Fix u-boot installation.</a><span class='msg-avail'>...<span class='msg-tooltip'>This is a follow-up of f19cf27c2b9ff92e2c0fd931ef7fde39c376adaa. The
bootloader installation must be done on the final disk-image, hence using
"disk-image-installer" instead of "installer" callback.

* gnu/bootloader/u-boot.scm: Turn all installer callbacks into
disk-image-installer callbacks.
* gnu/build/bootloader.scm (write-file-on-device): Open the output file with
'no-truncate and 'no-create options.
* gnu/system/image.scm (with-imported-modules*): Add (gnu build bootloader)
module.
</span></span></td><td>Mathieu Othacehe</td></tr>