The first thread would run fine. But the second thread would always cause a crash

I've tried running your code as-is and cannot get it to crash (over the space of a few runs) on my perl which is This is perl 5, version 20, subversion 3 (v5.20.3) built for x86_64-linux-thread-multi. To remove some possible sources of error I then made a few changes and come up with this, which I can't get to crash either.

#!/usr/bin/perl -l
use strict;
use warnings FATAL => 'all';
use threads;
use threads::shared;
use HTTP::Headers;
use LWP::UserAgent;


my $counter_thread : shared;

sub getgoog {
    my $method = "GET";
    my $uri = "https://www.google.com/";
    my $header = HTTP::Headers->new();
    $header->push_header("Content-Type" => "application/json");

    my $ua = LWP::UserAgent->new;
    $ua->ssl_opts(verify_hostname => 0, SSL_verify_mode => 0x00);

    my $request = HTTP::Request->new();
    $request->method($method);
    $request->uri($uri);
    $request->headers($header);
    my $response = $ua->request($request);

    print $counter_thread++, "th :", "Dumped Data Returned:\n\n ", sub
+str ($response->decoded_content, 0, 256);

    print "Response code:  ", $response->code, "\tHTTP Response Messag
+e: ",
        $response->message, " ";

    print "Thread id: ", threads->tid(), "\n";
}

my $thra = threads->create (\&getgoog);
$thra-> join;
my $thrb = threads->create (\&getgoog);
$thrb-> join;
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For clarity, the changes are:

• De-duplicated the sub as both appear to be completely identical.
• Remove the unused Threads::Queue
• Removed use of Dumper (because it's acting on a scalar string)
• Avoided use of the specials $a and $b
• Truncated the output for visualisation reasons

What happens if you try running my code? You might also want to consider experimenting with not making warnings fatal.