[perl #76102] [BUG] Null PMC access when calling a multi method on a class doing a role with a variant method whose signature contains a subtype of Hash... in Rakudo

[Carl Mäsak]

# New Ticket Created by  "Carl Mäsak" 
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<masak> rakudo: subset H of Hash; role R { method x(H $project) {} };
class A does R { multi method x($project) {} }; A.new.x({ a => "b" })
<p6eval> rakudo 4e6cce: OUTPUT«Null PMC access in invoke()␤  in
'ACCEPTS' at line 1 [...]
* masak submits rakudobug
<masak> "multi method killed in tragic Null PMC accident involving a
role and a subtype".
<masak> rakudo: subset H of Int; role R { method x(H $project) {} };
class A does R { multi method x(H $project) { say "OH HAI" } };
A.new.x(42)
<p6eval> rakudo 4e6cce: OUTPUT«OH HAI␤»
<masak> and the Hash type seems to be involved in the collision as well.