Integer overflow: Difference between revisions

Revision as of 00:58, 27 September 2011

Revision as of 20:03, 28 September 2011

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[[Image:Odometer_rollover.jpg|thumb|250px|[[Odometer]] rollover, a mechanical form of integer overflow. All digits are set to the maximum 9, and adding 1 causes a cascade of carry-over additions setting all digits to 0 but there is no higher digit to change to a 1, so the counter resets to zero.]]

In [[computer programming]], an '''integer overflow''' occurs when an [[arithmetic]] operation attempts to create a numeric value that is largertoo thanlarge canto be represented within the available storage space. For instance, adding 1 to the largest value that can be represented constitutes an integer overflow. The most common result in these cases is for the least significant representable bits of the result to be stored (the result is said to ''wrap''). On some processors like [[Graphics processing unit|GPU]]s and [[Digital signal processor|DSP]]s, the result [[saturation arithmetic|saturates]]; that is, once the maximum value is reached, attempts to make it larger simply return the maximum result.