I know this must be well-documented somewhere ... but ... where, exactly?

 [perldoc://patch] patch -> perlhack, perlrepository -> http://perl5.git.perl.org/perl.git

*theotherday* -> Blog post on hardening Perl's hash function -> Hardening Perl's Hash Function
maint-5.8: 2674b61957c26a4924831d5110afa454ae7ae5a6
maint-5.10: f14269908e5f8b4cab4b55643d7dd9de577e7918
maint-5.12: 9d83adcdf9ab3c1ac7d54d76f3944e57278f0e70
maint-5.14: d59e31fc729d8a39a774f03bc6bc457029a7aef2
maint-5.16: 6e79fe5714a72b1ef86dc890ff60746cdd19f854