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When the ideal result of an integer operation is outside the type's representable range and the returned result is obtained by clamping, then this event is commonly defined as a saturation. Use varies as to whether a saturation is or is not an overflow. To eliminate ambiguity, the terms wrapping overflow<ref>{{cite web |url=https://www.mathworks.com/help/simulink/gui/wrap-on-overflow.html?searchHighlight=overflow&s_tid=doc_srchtitle |title=Wrap on overflow - MATLAB & Simulink |website=www.mathworks.com}}</ref> and saturating overflow<ref>{{cite web |url=https://www.mathworks.com/help/simulink/gui/saturate-on-overflow.html?searchHighlight=overflow&s_tid=doc_srchtitle |title=Saturate on overflow - MATLAB & Simulink |website=www.mathworks.com}}</ref> can be used.
Integer Underflow is an improper term used to signify the negative side of overflow. This terminology confuses the prefix "over" in overflow to be related to the [[Sign (mathematics)|sign]] of the number. Overflowing is related the boundary of bits, specifically the number's bits overflowing. In [[Two's complement|two's complement]] this overflows into the sign bit. Many references can be found to integer underflow, but lack merit. For example: CWE-191 provides two code examples that are classic overflow and cast exceptions. CWE-191 then circularly references ''24 Deadly Sins of Software Security''
<ref>{{cite web |url=https://cwe.mitre.org/data/definitions/191.html |title=CWE - CWE-191: Integer Underflow (Wrap or Wraparound) (3.1) |website=cwe.mitre.org}}</ref>. This book does not define or give examples to integer underflow<ref>{{cite book |title=24 Deadly Sins of Software Security|last=Le Blanc|first=David|page=120}}</ref>.
Apple's developer's guide similarly uses the term in a section titled, "Avoiding Integer Overflows and Underflows" but then the section examines overflows without defining or talking about integer underflows<ref>{{cite web |url=https://developer.apple.com/library/content/documentation/Security/Conceptual/SecureCodingGuide/Articles/BufferOverflows.html#//apple_ref/doc/uid/TP40002577-SW7 |title=Avoiding Buffer Overflows and Underflows |website=developer.apple.com}}</ref>. This term can also be found in bug reports and changelogs. The term maybe used improperly by the bug reporter or inexperienced engineer. These always result in a fix that is explained by another known error type such as overflow, array boundary, or improper casting<ref>{{cite web |url=https://www.mozilla.org/en-US/security/advisories/mfsa2015-147/ |title=Integer underflow and buffer overflow processing MP4 metadata in libstagefright |website=Mozilla}}</ref>. Although underflow is not possible on integer operations, [[Arithmetic underflow|arithmetic underflow]] is possible on [[Floating-point arithmetic|floating-point operations]].
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