Somehow, in the last few days I stumble more over perl peculiarities, than in last few years :)

Again. I wanted to check how perl handles memory when I use substr($a, 0, 1) = ''. So I've used Devel::Peek to try the following code 

use Devel::Peek 'Dump';
use strict;

my $a = "test";
substr($a, 0, 2) = '';
Dump $a;

[download]
To my surprise it has produced the output 
SV = PV(0x22d3088) at 0x22f1968
  REFCNT = 2
  FLAGS = (PADMY,POK,OOK,pPOK)
  OFFSET = 2
  PV = 0x22e26b2 ( "t\2" . ) "st"\0
  CUR = 2
  LEN = 6
REFCNT is 2! Why? At first I thought, that this has something to do with the Devel::Peek, but after checking few other situations, I'm sure, that this happens only when I use substr to modify the content of the variable. Is there some internal reason for incrementing the reference count for the variable, or it is just a bug?

In reply to is this a memory leak or do I miss something? by andal

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