Architecture-specific module conflicts under perlbrew

gnosti has asked for the wisdom of the Perl Monks concerning the following question:

Dedicated monks!

I'm in search of wisdom regarding perlbrew, specifically about controlling where perlbrew installs architecture-specific (i.e. compiled) modules.

I have installed perlbrew in standard fashion, used it to install a few versions of perl, and then installed some modules. But my architecture-specific files are going to a common tree, leading to this type of error:

$ which perl
/home/jroth/perl5/perlbrew/perls/perl-5.16.3/bin/perl
perl -M JSON::XS -e 1
Perl API version v5.14.0 of JSON::XS does not match v5.16.0 at /home/j
+roth/perl5/perlbrew/perls/perl-5.16.3/lib/5.16.3/XSLoader.pm line 92.
Compilation failed in require.
BEGIN failed--compilation aborted.
[download]

Where did JSON::XS get installed?

 find /home/jroth/perl5 -name XS.pm | grep JSON
/home/jroth/perl5/lib/perl5/x86_64-linux/JSON/XS.pm
[download]

A shared directory! And where is my current perl looking for modules?

perl -E 'say join $/, @INC'
/home/jroth/perl5/lib/perl5/x86_64-linux-gnu-thread-multi
/home/jroth/perl5/lib/perl5/x86_64-linux
/home/jroth/perl5/lib/perl5
/home/jroth/perl5/perlbrew/perls/perl-5.16.3/lib/site_perl/5.16.3/x86_
+64-linux
/home/jroth/perl5/perlbrew/perls/perl-5.16.3/lib/site_perl/5.16.3
/home/jroth/perl5/perlbrew/perls/perl-5.16.3/lib/5.16.3/x86_64-linux
/home/jroth/perl5/perlbrew/perls/perl-5.16.3/lib/5.16.3
[download]

Does my environment have anything to do with this?

env | grep -i perl5lib
PERL5LIB=/home/jroth/perl5/lib/perl5/x86_64-linux-gnu-thread-multi:/ho
+me/jroth/perl5/lib/perl5
[download]

Did I do that?

grep -i perl5lib ~/.bashrc ~/.bash_profile
(n/t)
[download]

It appears I have two problems:

1. Under perlbrew, CPAN clients install architecture-specific files in a common tree, i.e.

/home/jroth/perl5/lib/perl5/x86_64-linux-gnu-thread-multi
/home/jroth/perl5/lib/perl5/x86_64-linux
[download]

even though these compiled files are most certainly incompatible across perl versions.

2. Under perlbrew, perl looks for architecture-specific files in a common tree, even though there are appropriate directories specific to each version of perl, i.e. one of

/home/jroth/perl5/perlbrew/perls/perl-5.16.3/lib/site_perl/5.16.3/x86_
+64-linux
/home/jroth/perl5/perlbrew/perls/perl-5.16.3/lib/site_perl/5.16.3
/home/jroth/perl5/perlbrew/perls/perl-5.16.3/lib/5.16.3/x86_64-linux
/home/jroth/perl5/perlbrew/perls/perl-5.16.3/lib/5.16.3
[download]

My questions are then, how to to set the preferences for a CPAN client under perlbrew to install to the latter set of directories (whether arguments, environment settings or patches?)

And similarly, to remove the former architecture-specific-shared directories from the PERL5LIB environment variable.

I'm confused that with perlbrew being around so long and having such a good reputation, no else seems to have this fundamental complaint and no bug has been filed against perlbrew on this issue.

Well there is a question at stackoverflow How can Install multiple Perl versions without them tripping over each other's XS modules? although the only answer is brian d foy's "don't use perlbrew, give each perl binary a version, i.e. perl-5.16.3 and let them find their own installed modules".

And there is Kent NL's post, although I didn't find it helpful, as cpanm clients continued installed to the shared tree, even after installing cpanm for each perl version.

Thanks for your interest and support!

UPDATE: For reasons unclear, my PERL5LIB environment variable is no longer set, and perlbrew is now behaving properly. I think it's possible that one of the terminals I was working had retained environment settings from local::lib, even after I had cleaned out those settings from .bashrc.

UPDATE 2: I've filed a bug against perlbrew, suggesting a warning on detecting any non-null PERL5LIB setting.

Comment on Architecture-specific module conflicts under perlbrew Select or Download Code

Replies are listed 'Best First'.
Re: Architecture-specific module conflicts under perlbrew by Anonymous Monk on May 16, 2013 at 05:12 UTC
Does my environment have anything to do with this? You check that with `perl -V` command, because PERL5LIB isn't the only one Although even that won't dump your cpan\|cpanp\|cpanm configurations Under perlbrew, CPAN clients install architecture-specific files in a common tree, i.e. That doesn't seem like a perlbrew issue :) see INSTALL_BASE Although you could argue if perlbrew doesn't protect you from yourself ( from your INSTALL_BASE overrides ) what is perlbrew good for? An alternative to perl brew (not a bash script) is perlall - build, test and do with all perls Although, it's about as easy to manage multiple perl's yourself without either, for how I do it see sh Configure -Dprefix=~/p-5.8.1/, win32 configure steps/Fix_pl2bat	[reply] [d/l]
Re^2: Architecture-specific module conflicts under perlbrew by gnosti (Chaplain) on May 16, 2013 at 19:53 UTC
Thanks. Once again, EU::MM shows it's still boss! If I can figure out what these environmental variables should be, I'll look into a patch to code or docs to help perlbrew be friendlier to a naive user.	[reply]
Re^3: Architecture-specific module conflicts under perlbrew by Anonymous Monk on May 17, 2013 at 19:54 UTC
Thanks. Once again, EU::MM shows it's still boss! If I can figure out what these environmental variables should be, I'll look into a patch to code or docs to help perlbrew be friendlier to a naive user. Maybe you want to simplt=y check first that your %ENV/cpanconfigs aren't overriding any of those settings?	[reply]
Re: Architecture-specific module conflicts under perlbrew by karlgoethebier (Abbot) on May 16, 2013 at 16:34 UTC
I tried to reproduce this under Mac OS X Mountain Lion with 5.16.2 as well as with 5.16.3. I couldn't, everything looks good and works. I skip the details, please believe me for now ;-) Nice for me but that doesn't help, OK. On the other hand, as far as i understood your `XS.pm` is in your `@INC`. IMHO it can be everywhere, even in `/nose/cuke` as long as you declare this. At my system(s), it is in a `site_perl` directory, where it belongs. Just now i tried it under Mac OS X Lion: `./perl5/perlbrew/perls/perl-5.16.2/lib/site_perl/5.16.2/darwin-2level/ +JSON/XS.pm` [download] And it works too. So why not opening an issue at github and ask for help? Update: I'm very interested in learning about this because i just started using `perlbrew`. I have it on two Macs for devel and on one ~~SLES11~~ Debian box for testing my new Icinga/Nagios... I hope, that i didn't miss something and best regards, Karl P.S.: I assume, you did the setup as described in the sources you mentioned - and you use `cpanm`... �The Crux of the Biscuit is the Apostrophe�	[reply] [d/l] [select]
Re^2: Architecture-specific module conflicts under perlbrew by gnosti (Chaplain) on May 16, 2013 at 19:14 UTC
Yes, XS.pm got installed to the wrong directory in my @INC, an arch-specific but perl version-agnostic directory that should not even exist! You're right about opening an issue, although the previous reply suggests I might be able to get the correct behavior by setting the appropriate environment variables. Usually I come to PM first with my problems because they are more often due to my own ignorance than to a bug. Thanks and good luck with your various boxen.	[reply]
Re^3: Architecture-specific module conflicts under perlbrew by karlgoethebier (Abbot) on May 16, 2013 at 21:15 UTC
�Yes, XS.pm got installed to the wrong directory in my @INC...� But you don't get this well known message: `Karls-Mac-mini:~ karl $ perl -MFOO Can't locate FOO.pm in @INC (@INC contains: #...bla, bla` [download] You get `Perl API version v5.14.0...Compilation failed in require`. That damned thing seems to be available - perhaps a bad place, but it is in your `@INC`, isn't it? Totally stupid "brute force" approach: Copy that thing to a place where you think it belongs (in `@INC`). Do you still get this compile time error? Or do i still miss something? Best regards, Karl �The Crux of the Biscuit is the Apostrophe�	[reply] [d/l] [select]
Re^4: Architecture-specific module conflicts under perlbrew by gnosti (Chaplain) on May 16, 2013 at 22:29 UTC
Re^5: Architecture-specific module conflicts under perlbrew by karlgoethebier (Abbot) on May 17, 2013 at 07:49 UTC
Some notes below your chosen depth have not been shown here
Re^5: Architecture-specific module conflicts under perlbrew by karlgoethebier (Abbot) on May 18, 2013 at 10:28 UTC


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