#! perl -slw

use strict;
use threads;
use threads::shared;

our %h : shared;

# Setting up just a single row to increase chances
# a race condition
our $k = 'AAA';
our $val : shared = 0;
our $THREADS = 50;
our $iter = 50;
$h{$k} = \$val;

# Safe_set similar to BrowserUk
sub safe_set {
  # Critical Section
  {
     lock ${$h{$k}};
      ${ $h{$k} } = ${ $h{$k}   } + 1;
  }
}

# Keep locking to increment $$h{$k}
sub test_safe_set {
  for (my $i = 0; $i < $iter; ++$i) {
     safe_set();
  }
}

my @pool = map{
      threads->create(\&test_safe_set)
    } 1 .. $THREADS;

$_->join for @pool;

warn ${$h{$k}}, "failed\n" if ${$h{$k}} != $THREADS * $iter;