I've just pushed smoke-me/avar/warn-grep-void-ctx which adds support for adding new warnings that aren't enabled by "use warnings", but rather by e.g. "use warnings qw(pedantic)". See http://perl5.git.perl.org/perl.git/log/refs/heads/smoke-me/avar/warn-grep-void-ctx These warnings are still turned on by -W on the command-line, and I haven't yet updated any of the warnings.pm docs to be less confusing in the face of this change. But this I think is a viable way forward to bring controversial warnings into the core without making it a pain to run existing code on new perl versions. To that end the patch brings back a warning that was removed from blead already over objections about it not belonging in the default set of warnings. Hopefully it and other similar warnings will cause no such objections when authors have to explicitly opt-in to view them.Thread Next