Coro/EV bug

#!/usr/bin/perl
use 5.14.0;
use warnings;

use Coro;
use EV;
use AnyEvent;
use Coro::AnyEvent;
use Coro::Handle;

my $line1;
my $line2;
my $worker = async {
    my $fh = unblock \*STDIN;

    eval {
        $line1 = $fh->readline;
    };
    if ($@) {
        $line1 = "interrupted reading first line: $@";
    }

    eval {
        $line2 = $fh->readline;
    };
    if ($@) {
        $line2 = "interrupted reading next line: $@";
    }
};

Coro::AnyEvent::sleep(1);
$worker->throw("interrupt\n");
$worker->ready;
$worker->join;

print $line1, $line2;
__END__

If nothing is entered on stdin in the first second, we expect $line1 to be
"interrupted reading first line: interrupt\n"
but also $line2 ends up as
"interrupted reading next line: recursive invocation of readable_ev or writable_ev (concurrent Coro::Handle calls on same handle?), detected at /usr/lib/perl5/Coro/Handle.pm line 551.\n"

I appreciate you can't use the same Coro::Handle instance simultaneously from two coroutines, but here only one coroutine is using it.

This is a simplified test case. The use of throw() is desired for other reasons; I know there are other possible approaches in this example.