Fixed with https://github.com/perl6/nqp/commit/2d88d98201
I'm closing this ticket as 'resolved'.
For the records: This works with '--optimize=off' (as psch++ has shown in the
linked discussion on #perl6).
$ ./perl6-j --optimize=off -e 'my $value = 42 but False; say ?$value'
False
The optimizer adds a QAST::Want for the mixin which the JVM backend does not
handle correctly.
$
# New Ticket Created by Will Coleda
# Please include the string: [perl #126491]
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# https://rt.perl.org/Ticket/Display.html?id=126491 >
This test from integration/advent2010-day19.t works on moar, but not on the JVM.
16:33 <