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Plain chars within structs? - gs - 18-03-2010
The commentary for rule 6.1 and 6.2 states
Quote:The permissible operators on plain char types are the simple assignment operator (=), equality operators (==, !=) and explicit casts to integral types. Additionally, the second and third operands of the ternary conditional operator may both be of plain char type.What about the '.' operator? Or the '->' operator? Could not an object of structure type contain a plain char member, making that member the second operand of the operator?
What about bit addressing or sizeof?
Re: Plain chars within structs? - gs - 24-03-2010
Or taking the address of a plain char object?
Re: Plain chars within structs? - jbezem - 25-03-2010
Using . or -> or & on a variable is IMHO not an operation on the _value_ of that variable (or struct member, so it's in a different category. Maybe the wording should be more clear that assignment and comparison (for instance) are operating on the values, the address operator is providing meta-information (the address, not the value), and . and -> are providing meta-information on the struct.
FWIW,
Johan
Re: Plain chars within structs? - gs - 06-04-2010
Perhaps; however, the wording of the guidelines state:
Quote:The permissible operators on plain char types are the simple assignment operator ...(Emphasis added.) The guidelines do not appear to limit the restriction to values; hence, my confusion.
Re: Plain chars within structs? - misra-c - 13-05-2010
Neither '.' nor '->' operates on char type even though they may yield a result of char type. Therefore they are both permitted by Rules 6.1 and 6.2.
The supporting text restricts operations on char type to assignment, equality, conditional operations and certain type-casts. The sizeof and & operators should also have appeared in this list of permitted operations.