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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.

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

ISO/IEC TR 24772 "KOA Likely Incorrect Expressions"

MITRE CWE: CWE-480, "Use of Incorrect Operator"

Bibliography

\[Hatton 1995\] Section 2.7.2, "Errors of omission and addition" 

      03. Expressions (EXP)      EXP18-C. Do not perform assignments in selection statements