Data::Alias and op_private flag assertions

Data::Alias adds its own private flags to certain ops.  So it trips on
the assertion failure recently added to make sure that no ops have
invalid private flags set.

I'm wondering about the best approach to solve this.  (I'm trying to
patch Data::Alias for other issues, but this one is now preventing all
tests from passing for me.)  Adding an op-freeing hook or registering
a custom op seems like overkill (and I'm not sure of all the implica-
tions of the latter).

So would it be acceptable to skip the private flag check if the ppaddr
has been reassigned?  That would make this kind of hackery slightly
easier.  And the assertion failure is happening for cosmetic rea-
sons anyway.

• Data::Alias and op_private flag assertions by Father Chrysostomos
• Re: Data::Alias and op_private flag assertions by Dave Mitchell