Dear Monks, I'm trying to speed up animated GIF generation with MCE::Map as shown in Re^3: Animated Heatmap but it crashes with "Segmentation fault: 11" or "Abort trap: 6". Here's the working code without MCE:

#!/usr/bin/perl

use strict;
use warnings;
use Imager;

STDOUT->autoflush;

my @i = ();

for my $x (0 .. 9999) {
  
  my $i = Imager->new(xsize=>120, ysize=>50)
  or die  Imager->errstr;
  
  $i->string(
    text  => $x,
    color => Imager::Color->new('ffffff'),
    font  => Imager::Font->new(
      file  => '/System/Library/Fonts/Courier.dfont',
#     face  => 'Courier New', # mswin
      size  => 42,
      aa    => 1),
    x     => 5,
    y     => 35
  );
  
  push @i, $i;
  
  print "\r$x"
}

Imager->write_multi({
  file => 'gif.gif', type => 'gif', gif_loop => 0, gif_delay => 1
}, @i) or die Imager->errstr;

print " frame GIF done!\n";
[download]

Here's the broken version with MCE:

#!/usr/bin/perl

use strict;
use warnings;
use Imager;
use MCE::Map;

STDOUT->autoflush;

MCE::Map->init(
  max_workers => 4,
  chunk_size  => 1,
  init_relay  => ''
);

my @i = mce_map {
  my $x = $_;
  my $i = Imager->new(xsize=>120, ysize=>50)
  or die  Imager->errstr;
  
  MCE::relay { print "\r$x" };
  
  $i->string(
    text  => $x,
    color => Imager::Color->new('ffffff'),
    font  => Imager::Font->new(
      file  => '/System/Library/Fonts/Courier.dfont',
#     face  => 'Courier New', # mswin
      size  => 42,
      aa    => 1),
    x     => 5,
    y     => 35
  );

  # without next line: Segmentation fault 11
  # with next line: Abort trap: 6 malloc: *** error for object
  # $i
  
} [ 0 .. 9999 ];

MCE::Map->finish;

Imager->write_multi({
  file => 'gif.gif', type => 'gif', gif_loop => 0, gif_delay => 1
}, @i) or die Imager->errstr;

print " frame GIF done!\n";
[download]

What am I doing wrong? Thank you

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