is_constructor and is_destructor. (demangling_new): Initialize them. (demangle_ctor_dtor_name): Set them, if we detect a constructor or destructor. (demangle_v3_with_details, is_gnu_v3_mangled_ctor, is_gnu_v3_mangled_dtor): New functions. * include/demangle.h (enum gnu_v3_constructor_kinds, is_gnu_v3_mangled_ctor, enum gnu_v3_destructor_kinds, is_gnu_v3_mangled_dtor): New declarations.