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);
=75b2511cc1d422aa1420323a52342970aaa8ebd9'>tree</a><a href='/guix/commit/m4?id=75b2511cc1d422aa1420323a52342970aaa8ebd9'>commit</a><a href='/guix/diff/m4?id=75b2511cc1d422aa1420323a52342970aaa8ebd9'>diff</a></td><td class='form'><form class='right' method='get' action='/guix/log/m4'>
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<div class='path'>path: <a href='/guix/log/?id=75b2511cc1d422aa1420323a52342970aaa8ebd9'>root</a>/<a href='/guix/log/m4?id=75b2511cc1d422aa1420323a52342970aaa8ebd9'>m4</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/m4?id=75b2511cc1d422aa1420323a52342970aaa8ebd9&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2022-01-14 11:41:15 +0200'>2022-01-14</span></td><td><a href='/guix/commit/m4?id=03b45230d409c5f09e6ad18f23f313a13dbddb7d'>gnu: bootstrap: Add support for riscv64-linux.</a><span class='msg-avail'>...<span class='msg-tooltip'>On 7d93b21ab1c132990054372a9677c1639d54e631
    gnu: glibc-for-bootstrap: Update patch.

Run
    ./pre-inst-env guix build --target=riscv64-linux-gnu bootstrap-tarballs

Producing
    /gnu/store/4hdzva9i0wyyfbgj1lmqc1wkk644pv07-bootstrap-tarballs-0

With guix hash -rx
    1nj0fdgj08bbmfny01mp2blv7c3p2iciqh31zmf04ap5s7ygsqlp

* gnu/packages/bootstrap.scm (%bootstrap-executables): Add entries for
riscv64-linux.
(%bootstrap-guile-hash, %bootstrap-coreutils&amp;co, %bootstrap-binutils,
%bootstrap-glibc, %bootstrap-gcc): Add entry for riscv64-linux.
(raw-build-guile3): New procedure.
(make-raw-bag): Use raw-build-guile3 for riscv64-linux.
* guix/packages.scm (%supported-systems): Add riscv64-linux.
(%cuirass-supported-systems): Remove riscv64-linux.
* guix/utils.scm (target-64bit?): Add riscv64-linux.
* m4/guix.m4: Add riscv64-linux as a supported system.
* doc/guix.texi (GNU Distribution): Add riscv64-linux.
</span></span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2021-12-14 18:33:49 +0200'>2021-12-14</span></td><td><a href='/guix/commit/m4?id=08d15a24c90e597f1656c3c0c3dbccf2022517de'>build: Adjust 'courage level' of different systems.</a><span class='msg-avail'>...<span class='msg-tooltip'>* m4/guix.m4 (GUIX_ASSERT_SUPPORTED_SYSTEM): Add i586-gnu. Move
powerpc-linux to unsupported but not needing courage. Add mips64el-linux
to unsupported.
</span></span></td><td>Efraim Flashner</td></tr>