[perl #125100] Macro using unless block unusable

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# New Ticket Created by  Rob Hoelz 
# Please include the string:  [perl #125100]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=125100 >


The following macro:

    macro assert($cond) {
        quasi {
            unless {{{$cond}}} {
                die "assertion failed";
            }
        }
    }

fails with the following error when used:

    ===SORRY!===
    Cannot reference undeclared local 'pres_topic__1'

bad-macro.p6
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