Hello vr,

One can try loading IO::Handle before spawning workers. That alone is helpful for increasing reliability for modules that involve IO::*. I was able to reproduce threads failing but not after adding the IO::Handle line. Even tested with 100 threads without a delay between them.

use warnings;
use feature 'say';
use threads;
use Thread::Queue;

use IO::Handle;  # <-- important

my $q = Thread::Queue-> new;

my @gang = map async( sub {
    while ( defined( my $f = $q-> dequeue )) {
        require Compress::Zlib;
        say threads-> tid;
    }
}), 1 .. 8;

$q-> enqueue( $_ ) for 1 .. 8;
$q-> end;

$_-> join for @gang;

[download]

Kind regards, Mario

In reply to Re^3: Why isn't this code thread-safe? (MCE!) by marioroy
in thread Why isn't this code thread-safe? (Is "require" thread-safe??) by vr

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