[perl #125934] [BUG] &?ROUTINE changes to something else in gather in for loop

[Aleks-Daniel Jakimenko-Aleksejev via RT]

Still reproducible (2017.11,HEAD(e5b660e))

On 2015-08-28 10:05:31, FROGGS.de wrote:
> m: sub foo { say &?ROUTINE.perl; gather for 1 { say &?ROUTINE.perl; };
> gather for 1 { say &?ROUTINE.perl; } }; foo
> rakudo-moar 5fb81f: OUTPUT«sub foo () { #`(Sub|59748232) ...
> }␤Code.new␤Code.new␤»
> rakudo-moar 186223: OUTPUT«sub foo () { #`(Sub|53058688) ...
> }␤Code.new␤Code.new␤»
>
> m: sub foo { say &?ROUTINE.perl; for 1 { say &?ROUTINE.perl; }; gather
> for 1 { say &?ROUTINE.perl; } }; foo
> rakudo-moar 5fb81f: OUTPUT«sub foo () { #`(Sub|42434376) ... }␤sub foo
> () { #`(Sub|42434376) ... }␤Code.new␤»
> rakudo-moar 186223: OUTPUT«sub foo () { #`(Sub|54308288) ... }␤sub foo
> () { #`(Sub|54308288) ... }␤Code.new␤»
>
> m: sub foo($,$,$) { say &?ROUTINE.arity; for 1 { say &?ROUTINE.arity; };
> gather for 1 { say &?ROUTINE.arity; } }; foo 1, 2, 3
> rakudo-moar 5fb81f: OUTPUT«3␤3␤0␤»
> rakudo-moar 186223: OUTPUT«3␤3␤0␤»
>
> m: sub foo($,$,$) { say &?ROUTINE.arity; for 1 { say &?ROUTINE.arity; };
> gather for 1 { if 1 { say &?ROUTINE.arity } } }; foo 1, 2, 3
> rakudo-moar 5fb81f: OUTPUT«3␤3␤3␤»
> rakudo-moar 186223: OUTPUT«3␤3␤3␤»
>
> I expect that the &?ROUTINE in the gather also points to the foo subroutine.