Interoperability with older levels of IBM COBOL programs
There are some restrictions for Enterprise COBOL V5 and V6 programs to call or be called by (interoperate with) programs compiled with earlier versions of COBOL.
Enterprise COBOL V5 and V6 programs interoperability
Enterprise COBOL V5 and V6 programs cannot interoperate with OS/VS COBOL or VS COBOL II NORES programs in a single application. A COBOL run unit (Language Environment® enclave) that contains an Enterprise COBOL V5 or V6 compiled program must not contain any OS/VS COBOL or VS COBOL II NORES programs.
Note: Run
units that contain only COBOL programs compiled with Enterprise COBOL V4 or earlier
versions can interoperate with OS/VS COBOL and VS COBOL II NORES programs.
Programs
compiled with Enterprise COBOL V5 or V6 can interoperate
with programs compiled with VS COBOL II or later, based on the following
conditions and CALL types:
- Static calls. Enterprise COBOL V5 or V6 compiled programs
can be bound (link-edited) with the following
object modules or programs to form a single program object. The programs
within the program object can specify static calls to and from each
other.
- Programs that are compiled with VS COBOL II with the RES compiler option
- Programs that are compiled with any IBM® COBOL compiler versions subsequent to VS COBOL II
- Programs that are compiled with Enterprise COBOL V3 or V4
Note: Programs that were compiled with VS COBOL II with theNORES
compiler option in effect cannot interoperate with programs compiled with Enterprise COBOL V5 or V6. - Dynamic calls. Program modules that contain programs compiled with VS COBOL II with the RES option, or subsequent versions of COBOL can also interoperate with Enterprise COBOL V5 or V6 program objects by using dynamic CALL statements.
- DLL calls. Program modules that are compiled with earlier versions of COBOL that supported DLL linkage can interoperate with Enterprise COBOL V5 or V6 program objects by using DLL linkage.

How to find if you have OS/VS COBOL programs
To
find if you have OS/VS COBOL programs, you can:
- Use the Debug Tool Load Module Analyzer to scan load libraries for OS/VS COBOL programs.
Use the free COBOL Analyzer from http://cbttape.org/cbtdowns.htm to scan load libraries for OS/VS COBOL programs. It is named as File # 321 COBOL Analyzer from Roland Schiradin & post processor on that web page.
- Install the fix for APAR PM86742 to your Language Environment and look for a warning message about detected OS/VS COBOL programs at run time.
