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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 ARR30-C. Do not form or use out-of-bounds pointers or array subscripts.

Incrementing is equivalent to adding 1.

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Subtraction is between two operands of arithmetic type, two pointers to qualified or unqualified versions of compatible object types, or a pointer to an object type and an integer type. This rule only applies to subtraction between two operands of arithmetic type.  See ARR36-C. Do not subtract or compare two pointers that do not refer to the same array, ARR37-C. Do not add or subtract an integer to a pointer to a non-array object, and ARR30-C. Do not form or use out-of-bounds pointers or array subscripts for information about pointer subtraction.

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The C Standard, 6.5.7 paragraph 4 [ISO/IEC 9899:2011], states

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In almost every case, an attempt to shift by a negative number of bits or by more bits than exist in the operand indicates a bug (logic error). These issues are covered by INT34-C. Do not shift an expression by a negative number of bits or more bits than or by greater than or equal to the number of bits that exist in the operand.

Noncompliant Code Example

This noncompliant code example performs a left shift, after verifying that the number being shifted is not negative, and the number of bits to shift is valid.  The PRECISION() macro and popcount() function are explained in INT35-C. Use correct integer precisions. However, because this code does no overflow check, it can result in an unrepresentable value. 

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Compliant Solution

This compliant solution eliminates the possibility of overflow resulting from a left-shift operation:

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