[perl #41732] [BUG] parrot objects segfault on improper invoke override

[via RT]

# New Ticket Created by  Will Coleda 
# Please include the string:  [perl #41732]
# in the subject line of all future correspondence about this issue. 
# <URL: http://rt.perl.org/rt3/Ticket/Display.html?id=41732 >


The following (improper?) code segfaults: 

.namespace ['Foo'] 

.sub __invoke :method
  .param pmc a
  say 'hi'
.end 

.sub main :main
    $P0 = newclass "Foo"
    $P1 = new "Foo"
    $P1()
.end 

Removing the __invoke method generates a method not found error, avoiding 
the segfault. Removing the .param also avoids the segfault. Changing the 
override to "invoke :vtable" avoids the segault.