I think you may have missed the "...if (for example)..." part of my post?

But more than one SvNULL will be created

That's a shame. Think of the space that would be saved if all SV's that were undef, were pointers to a single, shared copy of undef with a COW flag set?

creates two SVs 36 bytes apart, which suggest you can't use anything larger than 12.

Yeah! Since posting, I looked at the addresses of consecutive elements of an array and 12 does appear to be the minimum I can rely upon.

Any thoughts on discovering the lowest and highest addresses?

Examine what is said, not who speaks.
Silence betokens consent.
Love the truth but pardon error.

In reply to Re^2: Circular reference testing. by BrowserUk
in thread Circular reference testing. by BrowserUk

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