Handle overflows in capacities more #45
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I was mentally applying the rule that capacity can never exceed isize::MAX as a precondition BUT this is the code necessary for enforcing that! In fixing this I broke the fact that this code was subtly relying on that overflow to allow usize::MAX ZSTs to be allocated (by only allocating space for the header). ZSTs previously actually worked fine, as the garbage overflowed value was always wiped out by multiplying by 0 to get the array size. Now we need to handle it more explicitly.
Gankra
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Gankra
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gonna merge this as, at very least, a strict improvement over the status quo |
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0.2.12 published |
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I was mentally applying the rule that capacity can never exceed isize::MAX as a precondition BUT this is the code necessary for enforcing that! In fixing this I broke the fact that this code was subtly relying on that overflow to allow usize::MAX ZSTs to be allocated (by only allocating space for the header). ZSTs previously actually worked fine, as the garbage overflowed value was always wiped out by multiplying by 0 to get the array size. Now we need to handle it more explicitly.
(also a driveby explanation for why #42 happened)