Open PL/I adheres to the calling conventions of the native architecture. Programs compiled by Open PL/I can be linked with object modules produced by other language products, and the resulting object program will run if the following conditions are met:
- The calling conventions used by other language product(s) also adhere to the calling conventions of the native architecture. Note that the system C compiler on UNIX and the Windows Visual C/C++ compiler meet this requirement.
- Declarations for formal and actual parameters in the calling and called programs must be written in their respective languages, so that the data representations assumed in the declarations agree with each other.