>perl -MDevel::Peek -e"sub f { my $s; Dump $s if $i++; $s='abc' } f;f"
SV = PV(0x238e44) at 0x182ee40
  REFCNT = 1
  FLAGS = (PADBUSY,PADMY)
  PV = 0x18250bc "abc"\0
  CUR = 3
  LEN = 4