in reply to My, what is "my" doing here?

Not sure what bareword error you're getting or expecting.  I do get a "Use of uninitialized value" warning (as expected), both as a one-liner and as a regular script, and with various versions of Perl (5.10.0 and later). 

$ perl -Mstrict -we 'my ($x,$y)=(0,0); if ($x eq my $y) {}' 
Use of uninitialized value $y in string eq at -e line 1.

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Re^2: My, what is "my" doing here?
by locked_user sundialsvc4 (Abbot) on Jan 27, 2012 at 13:21 UTC

    The thing that is really flummoxing me here, Eliya, is that so do I, in a one-liner, but that’s not what I am seeing in the larger script.

    perl -e 'use strict; use warnings; my $x=0; my $y=0; if ($x eq my $y) { print "meh"; }'
    Use of uninitialized value $y in string eq at -e line 1.

    (No message is produced, in this one-liner, if use warnings; is omitted, and of course, this is the behavior that I expect to see all the time.)

    But the large Perl file compiles with no such warnings at all!   And that is what is throwing me here.

    I can accept the notion of the use of my being legitimate here, and I expect the warning-message to appear in every case when use warnings; is used.   This is what I expected here.   But, in this particular instant case, “no warning!”   The end result is that a subtle bug went into a production situation, and the only way that it was found was by line-by-line eyeball inspection in which three out of four people looking at it (“Paris in the the spring” ...) saw only what they expected to see.

      But the large Perl file compiles with no such warnings at all!
      Of course. And so does the one liner. The warning is a run-time warning.

      Can you show a trimmed down version of the larger program, that, when run, does not produce the warning when you expect it to do?

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      But the large Perl file compiles with no such warnings at all
      The warning is not coming at compile-time. It is a run-time one.
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