[perl #129984] state var in where clause not properly initialised

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# New Ticket Created by  Wenzel Peppmeyer 
# Please include the string:  [perl #129984]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=129984 >


my $a where state $ = say "foo";
# OUTPUT: «»
# expected: «foo␤»

# the following does work
my $b where $ = say "foo";