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The following sections examine specific operations that are susceptible to integer overflow. The specific tests that are required to guarantee that the operation does not result in an integer overflow depend on the signedness of the integer types. When operating on small types (smaller than int integer convertion rules apply. The usual arithmetic convertions may also be applied to (implicitly) convert operands to equivalent types before arithmetic operations are performed. Make sure you understand implicit conversion rules before trying to implement secure arithmetic operations.

Addition

Addition in C is between two operands of arithmetic type, or between a pointer to an object type and an integer type. (Incrementing is equivalent to adding one.)

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