I'm having a problem making a patch to a module work which contains the following code:

/* sv contains "aa" i.e., SvPOK(sv) is true and pv="aa"
sv_2nv(sv);
cast_ok = SvNOK(sv);
/* now cast_ok contains 512! */
/* and SvNV(sv) is 0 */

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sv contains "aa" in pv and was created by $val = "aa". Printing SvPV_nolen confirms pv contains "aa". Since "aa" is not a valid double then why is SvNV true and why does SvNV return 0?

In reply to Why does sv_2nv on non-number look like an NV by mje

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