EXP17-C. Do not perform bitwise operations in conditional expressions

Do not use the bitwise AND (&, ampersand) or bitwise OR (|, pipe) operator in a conditional expression because this typically indicates programmer error and can result in unexpected behavior. Use & or | only for bitwise operations and use && or ||only for logical operations.  Conditional expressions consist of the expressions in the condition of a selection statement (if, switch), an iteration statement (do, while, for), or the ternary conditional operator (?:).

Noncompliant Code Example

In this noncompliant code example, a bitwise expression is used in a conditional expression.

if (!(getuid() & geteuid() == 0)) { 
  /* ... */ 
} 

Compliant Solution

This compliant solution uses the && operator for the logical operation within the conditional expression.

if (!(getuid() && geteuid() == 0)) {
  /* ... */
}

Automated Detection

Related Guidelines

Bibliography