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Integer values must not be allowed to wrap if they are used in any of the following ways:

• As an array index
• In integer operands of any pointer arithmetic
• As a length or size of an object
• As the bound of an array (for example, a loop counter)
• , including array indexing;
• the assignment expression for the declaration of a variable length array;
• the postfix expression preceding square brackets [] or the expression in square brackets [] of a subscripted designation of an element of an array object; and
• function arguments of type size_t or rsize_t (for example, As an argument to a memory allocation functionIn security-critical code).
  
  

Addition

Addition is between two operands of arithmetic type or between a pointer to an object type and an integer type. This rule only applies to addition between two operands of arithmetic type. ( See ARR37-C. Do not add or subtract an integer to a pointer to a non-array object and  and ARR30-C. Do not form or use out of bounds pointers or array subscripts for information about adding a pointer to an integer.) .

Incrementing is equivalent to adding 1.

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