But shouldn't there be a warning in 5.12?

There should have been a warning for that in perl 5.0.

Shouldn't the warning be consistent in 5.14?

Variables declared in a conditional always was "undefined" behavior. To quote perlsyn:

NOTE: The behaviour of a "my" statement modified with a statement modifier conditional or loop construct (e.g. "my $x if ...") is undefined. The value of the "my" variable may be "undef", any previously assigned value, or possibly anything else. Don't rely on it. Future versions of perl might do something different from the version of perl you try it out on. Here be dragons.

(emphasis mine). The perl-5.14.0 behavior (new warning) is consistent with the documentation, and a good thing.

Perl 6 - second systems done right

In reply to Re^3: Closure warning with Perl 5.14? by moritz
in thread Closure warning with Perl 5.14? by BerntB

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