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Integer overflow can be demonstrated through an odometer overflowing, a mechanical version of the phenomenon. All digits are set to the maximum 9 and the next increment of the white digit causes a cascade of carry-over additions setting all digits to 0, but there is no higher digit (1,000,000s digit) to change to a 1, so the counter resets to zero.
A range check is a check to make sure a number is within a certain range; for example, to ensure that a value about to be assigned to a 16-bit integer is within the capacity of a 16-bit integer (i.e. checking against wrap-around). This is not quite the same as type checking. [how?
Analogous storage constraints will be reached in 2106, where systems storing Unix time as an unsigned (rather than signed) 32-bit integer will overflow on 7 February 2106 at 06:28:15 UTC. Computer systems that use time for critical computations may encounter fatal errors if the year 2038 problem is not addressed.
In the C# programming language, or any language that uses .NET, the DateTime structure stores absolute timestamps as the number of tenth-microseconds (10 −7 s, known as "ticks" [80]) since midnight UTC on 1 January 1 AD in the proleptic Gregorian calendar, [81] which will overflow a signed 64-bit integer on 14 September 29,228 at 02:48:05 ...
For integers, the term "integer underflow" typically refers to a special kind of integer overflow or integer wraparound condition whereby the result of subtraction would result in a value less than the minimum allowed for a given integer type, i.e. the ideal result was closer to negative infinity than the output type's representable value ...
Although saturation arithmetic is less popular for integer arithmetic in hardware, the IEEE floating-point standard, the most popular abstraction for dealing with approximate real numbers, uses a form of saturation in which overflow is converted into "infinity" or "negative infinity", and any other operation on this result continues to produce ...
This can happen in multi-threaded environments, or even in single-threaded environments when other code (typically called in the destruction of some object) resets the global variable before the checking code. The following example shows a way to avoid this problem (see or ; cf. ). But at the cost of not being able to use return values:
Canaries or canary words or stack cookies are known values that are placed between a buffer and control data on the stack to monitor buffer overflows. When the buffer overflows, the first data to be corrupted will usually be the canary, and a failed verification of the canary data will therefore alert of an overflow, which can then be handled, for example, by invalidating the corrupted data.