package Report;
use Tie::Hash;

our @ISA = 'Tie::StdHash';

sub TIEHASH  {
    my $storage = bless {}, shift;
    $storage
}

sub STORE    {
    my ($this, $key, $value) = @_;
    my (@foo) = caller();

    my ($package, $filename, $line) = caller;
    print STDERR "Storing $key => $value in $this at $package, in $filename on line $line.\n";
    $this->{$key} = $value
}

package TheLoader;

use strict;
use warnings;

tie %SIG, 'Report';
$SIG{__WARN__} = sub {
        return if $_[0] =~ /inherited AUTOLOAD/;
        print STDERR 'stolen warn: ' . $_[0];
};

package UNIVERSAL;

sub AUTOLOAD
{
    print "AUTOLOAD\n";
}

1;

##</code><code>##

use strict;
use warnings;
use Bar;
use Foo;

foo();
warn "hi";
Foo::bar();
warn "hi";

##</code><code>##

package Foo;

sub bar {
    $SIG{__WARN__} = sub { 0; };
}

1;

##</code><code>##

use strict;
use warnings;
package Bar;

use TheLoader;

foo();
warn "hi";
warn "inherited AUTOLOAD here";

##</code><code>##

Storing __WARN__ => CODE(0x818e988) in Report=HASH(0x818e14c) at TheLoader, in TheLoader.pm on line 29.
AUTOLOAD
stolen warn: hi at Bar.pm line 8.
AUTOLOAD
stolen warn: hi at blah.pl line 7.
Storing __WARN__ => CODE(0x818cf68) in Report=HASH(0x818e14c) at Foo, in Foo.pm on line 4.
AUTOLOAD
AUTOLOAD
AUTOLOAD