misc software development snippets

I just ran a sudo yum update on my development CentOS 5.3 box. (upgrade to 5.4)

All went well, except two issues.

1. I had to rollback perl-Apache-DBI.noarch 1.07-1.el5.rf
(luckily, I knew about this one, and had an old package available, and there are no deps issues - whew)

The issue manifests itself as:
[Tue Nov 10 10:43:02 2009] [error] Global $r object is not available. Set:\n\tPerlOptions +GlobalRequest\nin httpd.conf at /usr/lib/perl5/vendor_perl/5.8.8/Apache/DBI.pm line 144.\nCompilation failed in require at (eval 2) line 1.\n
[Tue Nov 10 10:43:02 2009] [error] Can't load Perl file: perl_load.pl for server , exiting...

To rollback:
$ sudo yum remove perl-Apache-DBI
$ sudo rpm -ivh perl-Apache-DBI-1.06-1.el5.rf.noarch.rpm

2. synopsis: "Weak references are not implemented in the version of perl "

The issue manifests itself as:
Weak references are not implemented in the version of perl at /usr/lib/perl5/vendor_perl/5.8.8/SOAP/Lite.pm line 2447\nBEGIN failed--compilation aborted at /usr/lib/perl5/vendor_perl/5.8.8/SOAP/Lite.pm line 2447.\nCompilation failed in require,...
...
...
[Wed Nov 11 16:50:01 2009] [error] Can't load Perl file: perl_load.pl for server, exiting...

which seemed me to (incorrectly) initially look in SOAP::Lite. (it's a Scalar::Util warning) Luckily I had another box I had just updated and knew that the updated did in fact work.

here is a command line test, to check with:
% perl -e"use Scalar::Util qw( weaken );"
%

should return nothing, on my box it returned:
% perl -e"use Scalar::Util qw( weaken );"
Weak references are not implemented in the version of perl at -e line 1
BEGIN failed--compilation aborted at -e line 1.

I couldn't find Scalar::Util installed!?
$ yum list|grep perl |grep -i scalar
perl-Scalar-Defer.noarch 0.20-1.el5.rf rpmforge
perl-Scalar-List-Utils.x86_64 1.21-1.el5.rf rpmforge
perl-Scalar-Properties.noarch 0.13-1.el5.rf rpmforge
perl-Set-Scalar.noarch 1.24-1.el5.rf rpmforge
perl-Tie-Scalar-Timeout.noarch 1.33-1.el5.rf rpmforge

After some searching, it appears that it's part or perl core now.

Eventually, I stumbled onto:
% locate Util.pm
/usr/lib/perl5/5.8.8/CGI/Util.pm
/usr/lib/perl5/5.8.8/Hash/Util.pm
/usr/lib/perl5/5.8.8/List/Util.pm
/usr/lib/perl5/5.8.8/Scalar/Util.pm
/usr/lib/perl5/vendor_perl/5.8.8/CGI/Simple/Util.pm
/usr/lib/perl5/vendor_perl/5.8.8/Crypt/DSA/Util.pm
/usr/lib/perl5/vendor_perl/5.8.8/HTTP/Headers/Util.pm
/usr/lib/perl5/vendor_perl/5.8.8/Mail/Util.pm
/usr/lib/perl5/vendor_perl/5.8.8/Mail/SpamAssassin/Util.pm
/usr/lib/perl5/vendor_perl/5.8.8/Net/SFTP/Util.pm
/usr/lib/perl5/vendor_perl/5.8.8/Net/SSH/Perl/Util.pm
/usr/lib64/perl5/5.8.8/x86_64-linux-thread-multi/List/Util.pm
/usr/lib64/perl5/5.8.8/x86_64-linux-thread-multi/Scalar/Util.pm
/usr/lib64/perl5/vendor_perl/5.8.8/x86_64-linux-thread-multi/APR/Util.pm
/usr/lib64/perl5/vendor_perl/5.8.8/x86_64-linux-thread-multi/Apache/TestUtil.pm
/usr/lib64/perl5/vendor_perl/5.8.8/x86_64-linux-thread-multi/Apache2/ConnectionUtil.pm
/usr/lib64/perl5/vendor_perl/5.8.8/x86_64-linux-thread-multi/Apache2/RequestUtil.pm
/usr/lib64/perl5/vendor_perl/5.8.8/x86_64-linux-thread-multi/Apache2/ServerUtil.pm
/usr/lib64/perl5/vendor_perl/5.8.8/x86_64-linux-thread-multi/Apache2/Util.pm
/usr/lib64/perl5/vendor_perl/5.8.8/x86_64-linux-thread-multi/ModPerl/MapUtil.pm
/usr/lib64/perl5/vendor_perl/5.8.8/x86_64-linux-thread-multi/ModPerl/Util.pm
/usr/lib64/perl5/vendor_perl/5.8.8/x86_64-linux-thread-multi/Params/Util.pm

The only difference in the results of this and the box that works,
/usr/lib64/perl5/5.8.8/x86_64-linux-thread-multi/List/Util.pm
/usr/lib64/perl5/5.8.8/x86_64-linux-thread-multi/Scalar/Util.pm are not in the list, of the working box.

(I have no idea how those got there, or where they are from, except for what the obviously look like, rhel5/centos packages,...)

perl INC is loading those libs first too.

$ perl -e 'print join "\n", @INC'
/usr/lib64/perl5/site_perl/5.8.8/x86_64-linux-thread-multi
/usr/lib/perl5/site_perl/5.8.8
/usr/lib/perl5/site_perl
/usr/lib64/perl5/vendor_perl/5.8.8/x86_64-linux-thread-multi
/usr/lib/perl5/vendor_perl/5.8.8
/usr/lib/perl5/vendor_perl
/usr/lib64/perl5/5.8.8/x86_64-linux-thread-multi
/usr/lib/perl5/5.8.8

so to 'resolve' the issue, I did this.

% sudo mv /usr/lib64/perl5/5.8.8/x86_64-linux-thread-multi/List/Util.pm /usr/lib64/perl5/5.8.8/x86_64-linux-thread-multi/List/Util.pm-1.19-broken-with-5.8.8-27
% sudo mv /usr/lib64/perl5/5.8.8/x86_64-linux-thread-multi/Scalar/Util.pm /usr/lib64/perl5/5.8.8/x86_64-linux-thread-multi/Scalar/Util.pm-1.19-broken-with-5.8.8-27

This worked for me, although is probably not the 'correct way'. I'm still not sure exactly what happened to get into this state, or I'd file a bug somewhere.

ref: (1)http://www.gossamer-threads.com/lists/modperl/modperl/98113

(1)http://rt.cpan.org/Public/Bug/Display.html?id=36346

(2) http://www.perlmonks.org/?node_id=424737 A different approach to the situation. (in general, we try to do everything through yum/rpm packages)
(2)http://bugs.centos.org/view.php?id=3022 an old bug, which made me realize I had to figure it out
(2) http://www.bluequartz.us/phpBB2/viewtopic.php?t=106577&sid=17481305416e016b01a061acb4ac3f45