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Reject Int-wrapping multiarray dimension products - #31
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Compute MultiDimensionalIndexer dimension products with Long multiplyExact and fail construction when the true product does not fit in Int, so MultiArray cannot allocate from a wrapped size. Co-authored-by: Barry G Becker <barrybecker4@yahoo.com>
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Summary
Fixes #14
MultiDimensionalIndexernow multiplies dimension lengths as aLong(viaMath.multiplyExact) and rejects products that do not fit in a signedInt. That closes the hole where values such as[65537, 65537]wrapped to a small positive size, soMultiArraycould allocate and index as if only that truncated count existed.Public APIs are unchanged (
getDimensionProductremains private;getNumValuesstill returnsLong). The only bb4 consumer found (bb4-optimization’sNumericGlobalSampler) already assumes the grid count fits in a 32-bit int.Test plan
MultiDimensionalIndexerandMultiArrayreject[65537, 65537]withIllegalArgumentExceptionMultiDimensionalIndexerrejects a product that overflowsLong