The ‘@’ type descriptor is used for a pointer-to-non-static-member-data type. It is followed by type information for the class (or union), a comma, and type information for the member data.
The following C++ source:
typedef int A::*int_in_a;
generates the following stab:
Note that there is a conflict between this and type attributes (see String Field); both use type descriptor ‘@’. Fortunately, the ‘@’ type descriptor used in this C++ sense always will be followed by a digit, ‘(’, or ‘-’, and type attributes never start with those things.