1. A computer program product for facilitating processing in a computing environment, said computer program product comprising: a computer readable storage medium readable by a processing circuit and storing instructions for performing a method comprising: determining that a short pointer mode application has been loaded; reconfiguring, based on determining the short pointer mode application has been loaded, an address space configured for a long pointer mode environment, the address space having one portion addressable by short pointers of a defined size and another portion addressable by long pointers of another defined size, the reconfiguring comprising: obtaining a long pointer library; and loading the long pointer library in the one portion of the address space addressable by short pointers; determining whether a short pointer is to be used as a private pointer in a short pointer binary or as a shared pointer with a long pointer binary; and sharing the short pointer with the long pointer library, based on determining the short pointer is to be used as a shared pointer.