[perl #127254] Segmentation fault on recursive binding (my $x := (my $y := $x))

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# New Ticket Created by  Alex Jakimenko 
# Please include the string:  [perl #127254]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=127254 >


Code:
my $x := (my $y := $x);
say $x.WHAT;

Result:
Segmentation fault


Code:
my $x := (my $y := $x);
say $y.WHAT; # same for $y

Result:
Segmentation fault


Code:
my $x := (my $y := $x);
say $x.^methods;

Result:
Segmentation fault


Code:
my $x := (my $y := $x);
say $x.blah;

Result:
Cannot call method 'blah' on a null object
  in block <unit> at ./test.p6 line 3


So it's just a null object.