# New Ticket Created by J . David Lowe
# Please include the string: [perl #131983]
# in the subject line of all future correspondence about this issue.
# <URL: https://rt.perl.org/Ticket/Display.html?id=131983 >
This short program behaves dies on my system, apparently because the mixed-in
attribute is somehow "leaking" between the two threads (???):
```
#!/usr/bin/env perl6
await((^2).map: {
start {
for (^10) -> $i {
my $x = Str.new but role { has $.test = $i };
die "$i != " ~ $x.test unless $x.test == $i;
}
}
});
```
produces output like:
```
$ ./bug
Tried to get the result of a broken Promise
in block <unit> at ./bug line 3
Original exception:
1 != 2
in block at ./bug line 7
$ ./bug
Tried to get the result of a broken Promise
in block <unit> at ./bug line 3
Original exception:
3 != 4
in block at ./bug line 7
```
It's possible that what I'm doing in this code isn't *intended* to be
thread-safe, but if that's the case, I don't understand why (e.g. looking at
the code, the two threads appear to be completely isolated.)
More information:
```
$ perl6 --version
This is Rakudo version 2017.07 built on MoarVM version 2017.07
implementing Perl 6.c.
```
