Effect on original feature: Valid C++ 2003 code, compiled without traceable pointer support,
that interacts with newer C++ code using regions declared reachable may
have different runtime behavior.
Change: Standard function object types no longer derived from
std::unary_function or std::binary_function.
Rationale: Superseded by new feature; unary_function and
binary_function are no longer defined.
Effect on original feature: Valid C++ 2003 code that depends on function object types being derived from
unary_function or binary_function may fail to compile
in this International Standard.