$ 5.42t/bin/perl -MDevel::Peek -e'Dump( "zzz" . "zzz" )'
SV = PV(0x6110ea0263a0) at 0x6110ea0540a0
  REFCNT = 1
  FLAGS = (PADTMP,POK,IsCOW,READONLY,PROTECT,pPOK)
  PV = 0x6110ea080fc0 "zzzzzz"\0
  CUR = 6
  LEN = 16
  COW_REFCNT = 0

$ 5.40t/bin/perl -MDevel::Peek -e'Dump( "zzz" . "zzz" )'
SV = PV(0x5be570a973a0) at 0x5be570ac50c0
  REFCNT = 1
  FLAGS = (PADTMP,POK,READONLY,PROTECT,pPOK)
  PV = 0x5be570af23e0 "zzzzzz"\0
  CUR = 6
  LEN = 16