I am not sure it is a bug.

Does this not fall under the "if it looks like a function..." rule?

Nothing was getting stored anywhere so Perl discarded it.

If you were to change to 

my $a = '0';
print "3f\n" if $a;

[download]
You don't get output. But you don't get the error.

In reply to Re: (MeowChow) Re2: Unusual 'constant in void context' warnings by Marza
in thread Unusual 'constant in void context' warnings by MeowChow

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