[perl #124255] SEGV with rakudo.moar when executing 'next; CONTROL { }'

[Christian Bartolomaeus via RT]

The segfault with MoarVM is fixed. The new error message seems LTA, though.

$ perl6-m -e 'next; CONTROL { }'
flatten requires a concrete string, but got null
  in regex  at ././CORE.setting.moarvm:1
  in block <unit> at -e:1