Protect fatpacked perlbrew from existing INC

[dagolden]

I found I had to modify my perlbrew to add this at the top so that I only had the system libraries (you could add vendor, too, I suppose).

BEGIN {
    use Config;
    @INC = @Config{qw(privlibexp archlibexp sitelibexp sitearchexp)};
}

Otherwise switching to/from a non-threaded perl to a threaded perl would break horribly with errors like this:

dyld: lazy symbol binding failed: Symbol not found: _Perl_xs_apiversion_bootcheck
  Referenced from: /Users/david/.perlbrew/libs/18.2t@std/lib/perl5/darwin-thread-multi-2level/auto/List/Util/Util.bundle
  Expected in: dynamic lookup

[karenetheridge]

It's not just threaded/non-threaded that is a problem - I ended up with older PERL5LIB interfering when I ran perlbrew exec --with $libdir cpanm $modulename.

e.g. see the output of 'perl -V' at http://www.cpantesters.org/cpan/report/9b3fbfa8-b568-11e3-928b-d94f618938b0

[karenetheridge]

The exact code I used to create the lib dir is at https://github.com/karenetheridge/misc/blob/master/install/generic/bin/newperl (around line 121).

[dagolden]

ping. Could this please be fixed? It's a major stumbling block for any serious use of perlbrew.

[dagolden]

I haven't tested this commit as I don't know how to set up a perlbrew for devel/build.sh, but I think it might do what we need.

[gugod]

Thanks @dagolden ... I push a build in the develop branch: https://github.com/gugod/App-perlbrew/blob/develop/perlbrew

If you could test it in your scenario, please let us know if it works. Thanks

[dagolden]

Thank you. If the only change is adding that line, I've been using it with a locally patched perlbrew for months, so it comes pre-tested. :-)

I remembered to pack it up as a pull request after having to get a co-worker set up with perlbrew.

[karenetheridge]

When I use this code, I experience more problems...

e.g. when starting off in a 5.21.1 perlbrew, and executing perlbrew use 21.2@std, I end up with this in perl -V:

Built under darwin
Compiled at Aug 6 2014 10:59:13
%ENV:
PERL5LIB="/Users/ether/.perlbrew/libs/21.2@std/lib/perl5:/Users/ether/.perlbrew/libs/21.1@std/lib/perl5"
PERLBREW_BASHRC_VERSION="0.69"
PERLBREW_HOME="/Users/ether/.perlbrew"
PERLBREW_LIB="std"
PERLBREW_MANPATH="/Users/ether/.perlbrew/libs/21.2@std/man:/Users/ether/perl5/perlbrew/perls/21.2/man"
PERLBREW_PATH="/Users/ether/.perlbrew/libs/21.2@std/bin:/Users/ether/perl5/perlbrew/bin:/Users/ether/perl5/perlbrew/perls/21.2/bin"
PERLBREW_PERL="21.2"
PERLBREW_ROOT="/Users/ether/perl5/perlbrew"
PERLBREW_VERSION="0.69"
PERLDOC_PAGER="less -sicMr"
PERL_AUTOINSTALL_PREFER_CPAN="1"
PERL_INSTALL_QUIET="1"
PERL_LOCAL_LIB_ROOT="/Users/ether/.perlbrew/libs/21.2@std:/Users/ether/.perlbrew/libs/21.1@std:/Users/ether/.perlbrew/libs/21.1@std"
PERL_MB_OPT="--install_base /Users/ether/.perlbrew/libs/21.2@std"
PERL_MM_OPT="INSTALL_BASE=/Users/ether/.perlbrew/libs/21.2@std"
@inc:
/Users/ether/.perlbrew/libs/21.2@std/lib/perl5
/Users/ether/.perlbrew/libs/21.1@std/lib/perl5/darwin-2level
/Users/ether/.perlbrew/libs/21.1@std/lib/perl5
/Users/ether/perl5/perlbrew/perls/21.2/lib/site_perl/5.21.2/darwin-2level
/Users/ether/perl5/perlbrew/perls/21.2/lib/site_perl/5.21.2
/Users/ether/perl5/perlbrew/perls/21.2/lib/5.21.2/darwin-2level
/Users/ether/perl5/perlbrew/perls/21.2/lib/5.21.2
.

PERL5LIB and PATH are being appended to, with the original perlbrew directories remaining.

[karenetheridge]

I see this just got released in version 0.70? IT IS BROKEN.

: [ether@bourbon ~]$; perlbrew use 20.0@std
: [ether@bourbon ~]$; 
: [ether@bourbon ~]$; echo $PERL5LIB
/Users/ether/.perlbrew/libs/20.0@std/lib/perl5:/Users/ether/.perlbrew/libs/20.0@std/lib/perl5
: [ether@bourbon ~]$; 
: [ether@bourbon ~]$; perlbrew use 21.3@std
: [ether@bourbon ~]$; 
: [ether@bourbon ~]$; echo $PERL5LIB
/Users/ether/.perlbrew/libs/21.3@std/lib/perl5:/Users/ether/.perlbrew/libs/20.0@std/lib/perl5:/Users/ether/.perlbrew/libs/20.0@std/lib/perl5

Now local::lib libraries from other versions of perl are being mixed in, which will cause all kinds of errors, including segmentation faults.

[gugod]

@karenetheridge I don't see how the original issue (%INC) is connected to having mixed PERL5LIB content... but that is indeed a breakage.

[karenetheridge]

I'm not sure either, but I initially discovered it when I edited the new code in this patch into my local installation (here: #387 (comment)).