[perl #132794] Junction as default value of MAIN param hangs forever

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# New Ticket Created by  Paweł Pabian 
# Please include the string:  [perl #132794]
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$ perl6 -e 'sub MAIN ( $x = 1|2 ) { }'

Following oneliner will hang forever on Rakudo 2018.01.
Error exists for all type of Junctions.
Doesn't matter if they are built by infix "1|2" or by method "any(1,2)".