Relinking

ILC applications that contain load modules with pre-Language Environment-conforming C routines or VS COBOL II programs must be relinked, either under Language Environment or with the migration tool provided in C/370 Version 2 Release 2. You should relink using the migration tool if your application will be used under both C/370 Version 2 Release 2 and Language Environment.

When you relink under Language Environment, explicitly include the following:

The @@C2CBL and @@CBL2C routines. @@C2CBL is called when a C routine calls a COBOL program. @@CBL2C is called (in C) when a C routine is designated as linkage COBOL.
IGZEBST or IGZENRI, depending on whether the COBOL program was compiled with RES or NORES, respectively.