Hash randomization broke a lot of CPAN modules that were relying on hash order (usually relying on it in the test suite). These were mostly caught during 5.17.x series, so if you've got recent versions of those modules, you'll be OK.
Amongst the affected distributions were DBI, libwww-perl, Catalyst-Runtime, DBIx-Class, Gtk2, Data-Visitor, PDF-API2, RDF-Trine, Template-Toolkit and Dancer (via MIME-Types). Many of these are major distributions that a lot of other distributions depend on.
package Cow { use Moo; has name => (is => 'lazy', default => sub { 'Mooington' }) } say Cow->new->name