As before, the C/C++ compiler takes the source program and produces an XOBJ. The binder has been extended to accept not only object modules (in all structures, for example, traditional, XOBJ and GOFF), load modules, program objects and z/OS UNIX files, as earlier, but also z/OS UNIX archive files and C370LIBs for autocall functions. It also accepts all prelinker control statements. In addition, a C renaming routine was added to the existing interface validation logic in the binder. The result is that the prelinker step can be eliminated when SYSLMOD specifies a PDSE program library because all the work previously performed by the prelinker is now done by the binder. (This control flow is shown on Figure 2.)

Eliminating the prelinker step has several advantages:

• Improved performance with the elimination of a job step
• Easier incorporation of new functions, released from the format restrictions imposed by an intermediate data structure
• Rebindable module as output, for example, it is not necessary to return to object files to rebind
• More efficient code distribution and servicing since single object files can be shipped in PTFs rather than the fully bound C module.

Figure 1. Invoking the prelinker. This diagram shows where the prelinker is invoked when the binder 'prelinker' function is not used.

Figure 2. Prelinker elimination. This is the optional control flow in the z/OS binder.