[perl #126724] [BUG] Unsatisfactory internal error when trying to compose two roles (connected with 'does') that share the same private attribute in Rakudo

Current behavior seems to be satisfactory now:

$ perl6 -e 'role R { has $.x }; role S does R { has $.x }; S.new;'
Attribute '$!x' conflicts in role composition

Test added in https://github.com/perl6/roast/commit/c65ed93912

closing.