[perl #113614] Undeclared variable in error message adds three null bytes between characters of the error message

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# New Ticket Created by  Moritz Lenz 
# Please include the string:  [perl #113614]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org:443/rt3/Ticket/Display.html?id=113614 >


< cognominal___> r: say '' ~~ /  $d /;
<+p6eval> rakudo 684fd2:
OUTPUT«=␀␀␀=␀␀␀=␀␀␀S␀␀␀O␀␀␀R␀␀␀R␀␀␀Y␀␀␀!␀␀␀=␀␀␀=␀␀␀=␀␀␀␤␀␀␀V␀␀␀a␀␀␀r␀␀␀i␀␀␀a␀␀␀b␀␀␀l␀␀␀e␀␀␀
 
␀␀␀$␀␀␀d␀␀␀ ␀␀␀i␀␀␀s␀␀␀ ␀␀␀n␀␀␀o␀␀␀t␀␀␀
                 ␀␀␀d␀␀␀e␀␀␀c␀␀␀l␀␀␀a␀␀␀r␀␀␀e␀␀␀d␀␀␀␤
< moritz> eeks
< cognominal___> weird.  It happened to me when I type $d instead  $<d> 
in a regex.
< cognominal___> at least, here it says sorry  :)
< moritz> well, here it adds lots of null bytes between the characters 
ofthe 'SORRY'
< moritz> .u ␀
< phenny> U+2400 SYMBOL FOR NULL (␀)