I would not consider your scenario to show that Perl is 'leaking' memory. Rather, Perl is allocating a bit more memory in a case that you expect should allocate the same or less memory.

Perl requires store to hold lexical variables. For functions that are called many times, but never recursively, Perl can reuse the same lexical variable storage ('pad') for each invocation. When a function is called recursively, new lexical variable storage needs to be allocated, because the previously available storage is currently in use.

The memory is not lost or 'leaked'. Simply, Perl doesn't have an appropriately sized memory block in its freelist, so it allocates a new one.

If you wanted to prove that the memory was actually leaked, you would need to show that multiple iterations of the recurse() function lost additional memory at each iteration. I do not believe that you will find this.

In reply to Re: Nested Calls, Recursion and MEMORY by MarkM
in thread Nested Calls, Recursion and MEMORY by robdog

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