__property keyword support in GCC

[Joe Buck]

> But I thought, that __property could be very easy added into GCC, because
> it only needs some new grammar rules, such as:
> 
> <property_construct> ::= __property <defined_type> <prop_name> { <prop_attr_list> };
> <prop_attr_list> ::= <prop_id> <prop_attr_list> | [];
> <prop_id> ::= <prop_type> = <class_member>;
> <prop_type> ::= read | write | ...;

Parsing the declaration of a property type is, as you say, relatively
simple.  But the main work would be the appropriate handling of property
symbols in all contexts, including all the contexts where they don't make
sense (attempts to create pointers or references to a property, etc), plus
debugger support (the gdb user would want to be able to refer to property
symbols).