The PR or ER in the importing class which represents the imported data must have the 'linkage type' field set to XPLINK. References to XPLINK data items should be A-type or V-type address constants (RLD reference type=0) contained in C_WSA or C_WSA64 when using reentrant code. References to XPLINK data items may be contained in any class when using non-reentrant code.