Qt-Generic-NoOverloadedOperators

Do not overload certain operators

Required inputs: IR

Programmers expect operator && and operator || to have short-circuiting behavior. As it is impossible for user-defined overloads of these operators to have the expected behavior, these operators should never be overloaded.

The built-in operator , introduces a "sequence before" relation between the left and right operands. However, user-defined operator overloads act like functions, and thus prior to C++17 do not have a defined sequence relation between their arguments. While in C++17 and later the arguments are sequenced to match the built-in operator, overloaded operator , may not match programmer expectations and should therefore be avoided.

Programmers expect the address-of operator operator & to return the address of its operand. User-defined overloads can lead to surprising behavior and should be avoided.

Bad code:

class S {
public:
    bool operator&&(const S& other) const; // ERROR: Do not overload operator&&.
    bool operator||(const S& other) const; // ERROR: Do not overload operator||.
    bool operator,(const S& other) const; // ERROR: Do not overload operator,.
    S *operator&() const; // ERROR: Do not overload operator&.
};

Possible Messages

Key	Text	Severity	Disabled
forbidden_operator_overload	Do not overload operator.	None	False

Options

• This rule shares the following common options: exclude_in_macros, exclude_messages_in_system_headers, excludes, extend_exclude_to_macro_invocations, includes, justification_checker, languages, post_processing, provider, report_at, severity

• The following places define options that affect this rule: Stylechecks, Analysis-GlobalOptions

invalid

invalid : set[str] = {'operator&&', 'operator,', 'operator||'}

Selection of disallowed operator overloads by name.

 

invalid_kinds

invalid_kinds

Type: set[Operator_Type]

Default: {'ADDRESS_OF'}

Selection of disallowed operator overloads by operator kind.

 

Option Types

These types are used by options listed above:

Operator_Type

An enumeration.

 

• NEW

• ARRAY_NEW

• ADD

• UNARY_PLUS

• MULTIPLY

• DEREFERENCE_STAR

• MODULO

• ADDRESS_OF

• BIT_AND

• BIT_NOT

• ASSIGN

• GREATER_THAN

• SUBTRACT_ASSIGN

• DIVIDE_ASSIGN

• BIT_XOR_ASSIGN

• BIT_OR_ASSIGN

• SHIFT_RIGHT

• SHIFT_LEFT_ASSIGN

• UNEQUAL

• GREATER_OR_EQUAL

• OR_ELSE

• PREFIX_DECREMENT

• POSTFIX_DECREMENT

• ARROW_STAR

• CALL

• CONDITIONAL

• GNU_MIN

• DELETE

• ARRAY_DELETE

• SUBTRACT

• UNARY_MINUS

• DIVIDE

• BIT_XOR

• BIT_OR

• LOGICAL_NOT

• LESS_THAN

• ADD_ASSIGN

• MULTIPLY_ASSIGN

• MODULO_ASSIGN

• BIT_AND_ASSIGN

• SHIFT_LEFT

• SHIFT_RIGHT_ASSIGN

• EQUAL

• LESS_OR_EQUAL

• AND_THEN

• PREFIX_INCREMENT

• POSTFIX_INCREMENT

• COMMA

• DEREFERENCE_ARROW

• ARRAY_ACCESS

• GNU_MAX

• THREE_WAY_COMPARE

• USER_DEFINED_LITERAL