Do your modules use each other (circularity)? I've seen similar things happen when you attempt to use methods prior to them being defined in the compile phase. I get a similar error with:

Foo.pm

package Foo;
use Bar;

sub new {
    return bless {}, shift;
}

1;
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Bar.pm:

package Bar;
use Foo;

sub new {
    return bless {}, shift;
}

my $foo = Foo->new();

1;
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script.pl:

#!/usr/bin/perl
use strict;
use warnings;

use Foo;
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