Clamp Vec::with_capacity to 64KiB to avoid OOM #1545
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Fuzz testers love to muck with length fields and trigger OOM panics. This is documented in #1459.
This PR fixes the linked issue, though my solution is not the suggested one. Rather than adding a new combinator, I've updated
many_m_nandcountto clamp theirVec::with_capacitycalls to 64KiB. This greatly reduces (though does not eliminate) the risk of OOM panics while still providing most of the benefit of preallocating memory.Clamping initial capacity to 64KiB does not affect correctness. Nom will still read the full number of elements. The initial capacity is just a performance hint.