Turns out it was easy to install on my Windows machine. It stops behaving "properly" when the eval is in a function. Warnings for both $foo and $bar are emitted as soon as the function is compiled. 
#!/usr/bin/perl

use warnings;
use warnings::unused;
use strict;

BEGIN { print("1\n"); }
sub foo {
   my $foo = 42;
   my $bar = 43;
   eval '$foo++';
   print("4\n");
   <>;                     # <-- Segfaults when this is executed.
}                          # <-- Warns when this is compiled
BEGIN { print("2\n"); }
print("3\n");
foo();
print("5\n");
<>;

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In reply to Re^7: Warnings on unused variables? by ikegami
in thread Warnings on unused variables? by AZed

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