Double the width of static allocations for empty tables #596
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clarfonthey
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I still don't think this is needed: the only place that needs |
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See this discussion here: #578 (comment)
Effectively, the current code will actually need
Group::WIDTH + 1bytes for an empty table, but we only allocateGroup::WIDTHbytes for it. This could potentially invoke UB based upon the invariants we set in the table, but because we happen to short-circuit empty tables in just the right ways in the actual code, we never actually trigger it.Since the static allocations are aligned to the group width, we double the size returned, since it would otherwise just add that much extra padding anyway. And since the size of the static allocations added by this is effectively insignificant (8-16 bytes depending on the implementation chosen), it's fair to just do this anyway to make the code more robust.