From @zoffixznet

# I have the fix; filing for records

If large-enough values are used for multiplication, we get 0 instead
of correct results​:

<Zoffix> m​: say (my int $ = 2**32) * (my int $ = 2**63)
<camelia> rakudo-moar 62d838​: OUTPUT«0␤»
<Zoffix> m​: say (my int $ = 2**62) * (my int $ = 2**62)
<camelia> rakudo-moar 62d838​: OUTPUT«0␤»

The fix is to add `or $a == 0 || $b == 0 ?? 0 !!
Failure.new(X​::Numeric​::Overflow.new)` after the calculation in
https://github.com/rakudo/rakudo/blob/62d8382/src/core/Int.pm#L262

However, that currently won't work entirely due to RT#​129811​:
https://rt-archive.perl.org/perl6/Ticket/Display.html?id=129811

From @zoffixznet

Fixed in rakudo/rakudo@8023dfbc6f
Test in Raku/roast@22408595d6

On Wed Oct 05 14​:43​:38 2016, cpan@​zoffix.com wrote​:

# I have the fix; filing for records

If large-enough values are used for multiplication, we get 0 instead
of correct results​:

<Zoffix> m​: say (my int $ = 2**32) * (my int $ = 2**63)
<camelia> rakudo-moar 62d838​: OUTPUT«0␤»
<Zoffix> m​: say (my int $ = 2**62) * (my int $ = 2**62)
<camelia> rakudo-moar 62d838​: OUTPUT«0␤»

The fix is to add `or $a == 0 || $b == 0 ?? 0 !!
Failure.new(X​::Numeric​::Overflow.new)` after the calculation in
https://github.com/rakudo/rakudo/blob/62d8382/src/core/Int.pm#L262

However, that currently won't work entirely due to RT#​129811​:
https://rt-archive.perl.org/perl6/Ticket/Display.html?id=129811

@zoffixznet - Status changed from 'new' to 'resolved'