in reply to Re^4: How to prevent references from stringifying?
in thread How to prevent references from stringifying?

Oops, I must have misread it as Perl_warner(aTHX_ "...") when I wrote the reply.

As for packWARN, perl 5.8 uses those while 5.6 didn't, hence you're not seeing them in your 5.6.2 source tree.

In Section Seekers of Perl Wisdom