Holy bloat, Batman!
Let's compare the latest constant.pm to a minimal equivalent:
$ ./perl -Ilib -le 'print $^V'; /usr/bin/time -l ./perl -Ilib -le 'use constant X => 1..5; print X' 2>&1 | grep 'maximum resident'
v5.17.10
3829760 maximum resident set size
$ /usr/bin/time -l ./perl -I/tmp -le 'use constant X => 1..5; print X' 2>&1 | grep 'maximum resident'
1200128 maximum resident set size
That's 2.6MB bloat to define a constant. (The culprit turns out to be
utf8, natch, to handle Unicode constants. (Why, God?!)). For reference,
/tmp/constant.pm…