After uploading Error-0.17010, I received several installation failures from testers who tested using perl-5.005. I wanted to simply deprecate perl-5.005, but I talked with my co-maintainer to see what he thinks about it. From what I understood, he wanted me to fix the problems that caused the failures on perl-5.005 and then to upload it again to see if it helps.
I didn't want to upload something without making sure the tests pass, because otherwise it will take a while to get it working. So I decided to install perl-5.005.
After downloading perl-5.005, the first thing I noticed was that running "make" failed immediately. This was due to a gcc-4.2 regression which can be fixed using this fix. Apparently it also affects more recent versions of perl5.
After applying the fix, everything compiled, and "make test" passed.
Error.pm requires Scalar::Util so I had to build it. As it turns out "perl5.005 Makefile.PL" does not work there properly for some reason, while "perl5.005 -d Makefile.PL" (and then "c" in the debugger) works fine.
Retrospectively I learned that it requires an up-to-date Test::Harness.
Error.pm also made use of the warnings module so I need to install warnings-compat. This in turn required Test-More, which is part of the Test-Simple distribution. This in turn required Test-Harness so I had to install Test-Harness-2.64, whose building worked. Then I backtracked until I had everything installed.
Now to Error.pm. I changed an open I, ">", "Changes" to open I, ">Changes". However, it still didn't work. There's one bug in the script 05text-errors-with-file-handles.t which works fine in perl-5.8.8. There were also failures in a script that my co-maintainer originally wrote, which I didn't understand.
So after all this work, I gave up. I told the co-maintainer that if he wanted to have Error working with perl-5.005, he should do the work himself. Otherwise, I'll just bump the minimum version to perl-5.6.x.
Triaging Error.pm with perl-5.005 made me realise how much the more modern perls are better to work with. I pity the people who still have to work with such old versions of perl.