>perl -MO=Concise -e"'foo'"
3  <@> leave[1 ref] vKP/REFC ->(end)
1     <0> enter ->2
2     <;> nextstate(main 1 -e:1) v ->3
-     <0> ex-const v ->3                  <-- The constant in void
-e syntax OK                                  context was removed
                                              from the execution path.