perl and libclass-xsaccessor-perl conflict in experimental

[Tim Woodall]

I know this is experimental and so breakage is expected but it seems to
have been like this for a while now so I'm reporting it here in case
it's been missed.

Apologies if there's some "obvious" resource I should be checking for
things like this but I couldn't find anything apparently related in my
searches or if this is perfectly normal for experimental but previous
breakages like this have been resolved in a day or two.

+ apt-get -o Acquire::http::Proxy=http://localhost:3128/ -o APT::Install-Recommends=false -o Dpkg::Options::=--force-confdef -o Dpkg::Options::=--force-confold -y --allow-unauthenticated install devscripts
Reading package lists...
Building dependency tree...
Reading state information...
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
libclass-xsaccessor-perl : Depends: perl (< 5.40.1~) but 5.40.1-1 is to be installed
E: Unable to correct problems, you have held broken packages.

+ apt-cache policy perl
perl:
Installed: 5.40.1-1
Candidate: 5.40.1-1
Version table:
*** 5.40.1-1 500
500 http://deb.debian.org/debian experimental/main amd64 Packages
100 /var/lib/dpkg/status
5.40.0-8 500
500 http://deb.debian.org/debian sid/main amd64 Packages

+ apt-cache policy libclass-xsaccessor-perl
libclass-xsaccessor-perl:
Installed: (none)
Candidate: 1.19-4+b4
Version table:
1.19-4+b4 500
500 http://deb.debian.org/debian sid/main amd64 Packages

+ apt-cache show libclass-xsaccessor-perl
Package: libclass-xsaccessor-perl
Source: libclass-xsaccessor-perl (1.19-4)
Version: 1.19-4+b4
Installed-Size: 111
Maintainer: Debian Perl Group <pkg-perl-***@lists.alioth.debian.org>
Architecture: amd64
Provides: libclass-xsaccessor-array-perl
Depends: perl (>= 5.40.0-6), perlapi-5.40.0, perl (<< 5.40.1~), libc6 (>= 2.14)
Description-en: Perl module providing fast XS accessors
Class::XSAccessor implements fast XS accessors both for getting at and setting
an object attribute. Additionally, the module supports mutators and simple
predicates like those for testing the truth value of a variable. It works only
with objects that are implemented as ordinary hashes.
.
The XS accessor methods were between 1.6 and 2.5 times faster than typical
pure-perl accessors in some simple benchmarking. If you usually write clear
code, a factor of two speed-up is a good estimate.
.
Refer to Class::XSAccessor::Array (also included in libclass-xsaccessor-perl)
for an implementation that works with array-based objects.
Description-md5: e785abcf076fde905048821573ca8b98
Homepage: https://metacpan.org/release/Class-XSAccessor
Tag: devel::lang:perl, devel::library, implemented-in::c,
implemented-in::perl, role::devel-lib, role::shared-lib
Section: perl
Priority: optional
Filename: pool/main/libc/libclass-xsaccessor-perl/libclass-xsaccessor-perl_1.19-4+b4_amd64.deb
Size: 36076
MD5sum: fb3838695620d92293c848fbef13fb98
SHA256: d0020012f2ae5ac0d456fbd7c21b6cfdd77653dd42e5cac0a0661f211de1ffe9

[Andrey Rakhmatullin]

Post by Tim Woodall
I know this is experimental and so breakage is expected but it seems to
have been like this for a while now so I'm reporting it here in case
it's been missed.

You may be confused, as perl 5.40.1-1 was only uploaded to experimental a
week ago, but also in general it's expected that stuff with a new ABI in
experimental is not installable in unstable. That's why we have
transitions. It also shouldn't be unique to libclass-xsaccessor-perl,
there are several packages in unstable that aren't coinstallable with a
too new perl.

Post by Tim Woodall
Apologies if there's some "obvious" resource I should be checking for
things like this

I'd say you are just not supposed to install random packages from
experimental...

[Niko Tyni]

Post by Andrey Rakhmatullin

Post by Tim Woodall
I know this is experimental and so breakage is expected but it seems to
have been like this for a while now so I'm reporting it here in case
it's been missed.

You may be confused, as perl 5.40.1-1 was only uploaded to experimental a
week ago, but also in general it's expected that stuff with a new ABI in
experimental is not installable in unstable. That's why we have
transitions. It also shouldn't be unique to libclass-xsaccessor-perl,
there are several packages in unstable that aren't coinstallable with a
too new perl.

Yes, this is indeed expected behaviour. We're using experimental as
a staging ground for testing out new upstream Perl releases to ensure
that the actual transition will be as painless as possible. Updating all
required reverse dependencies in experimental accordingly and keeping
them up to date would be too much of a burden however (and step on
other maintainers' toes), so we're using a separate test repository [1]
for that.

This is mostly geared for major Perl upstream releases, where 600+
packages need rebuilds. The minor Perl upstream releases (like 5.40.1
here) are ABI compatible, so most packages stay installable, but there's
still a handful of packages depending on the specific upstream version
they were built with for various reasons [2]. libclass-xsaccessor-perl
is one of these and will be rebuilt for Perl 5.40.1 when that enters
unstable.

FWIW my tests with 5.40.1 look good so far (both rebuilds and
autopkgtest), but I'm not quite finished yet.

[1] https://perl.debian.net/

[2] https://wiki.debian.org/PerlMaintenance#Point_releases_only

Post by Andrey Rakhmatullin
I'd say you are just not supposed to install random packages from
experimental...

Indeed.

[Tim Woodall]

Post by Niko Tyni

Post by Andrey Rakhmatullin

Post by Tim Woodall
I know this is experimental and so breakage is expected but it seems to
have been like this for a while now so I'm reporting it here in case
it's been missed.

You may be confused, as perl 5.40.1-1 was only uploaded to experimental a
week ago, but also in general it's expected that stuff with a new ABI in
experimental is not installable in unstable. That's why we have
transitions. It also shouldn't be unique to libclass-xsaccessor-perl,
there are several packages in unstable that aren't coinstallable with a
too new perl.

Yes, this is indeed expected behaviour. We're using experimental as
a staging ground for testing out new upstream Perl releases to ensure
that the actual transition will be as painless as possible. Updating all
required reverse dependencies in experimental accordingly and keeping
them up to date would be too much of a burden however (and step on
other maintainers' toes), so we're using a separate test repository [1]
for that.
[1] https://perl.debian.net/
[2] https://wiki.debian.org/PerlMaintenance#Point_releases_only

Post by Andrey Rakhmatullin
I'd say you are just not supposed to install random packages from
experimental...

Indeed.

Thanks both for the explanation. I was assuming that the intention of
experimental was that it should work in theory but things uploaded might
have bugs or other unexpected side effects that maintainers wanted
testing and I thought this failure might have been missed.