Enterprise Cobol v5 introduced changes to the compile options for program optimization. The previous OPTIMIZE/NOOPTIMIZE compile option has been replaced with OPTIMIZE(0), OPTIMIZE(1), or OPTIMIZE(2). The values following the option reflect the level of optimization; OPTIMIZE(0) essentially means NOOPTIMIZE while the other values increase the level and extent of the optimization that takes place during program execution. Another change to program optimization with Cobol V5 is the introduction of the new option STGOPT/NOSTGOPT. When turned on with STGOPT, unreferenced data items are discarded and no storage will be allocated for them. NOSTGOPT prevents the discarding of these items.
The use of program optimization, often has a negative effect upon the breakpointing capabilities and/or the display of the abending statement functions of the CA InterTest and CA Symdump products that use a PROTSYM file to store and display program source code. Since Optimization modifies the generated code, it may cause inconsistencies with the related source statements in a compile listing which remains static. The altered program flow often may not follow the saved code. IBM itself cautions against using optimization during testing. You can find the following statement included in the description of the OPTIMIZE compile option in the IBM Enterprise Cobol Programming Guides: “… specifying the OPTIMIZE option increases the compilation time and compilation storage requirements, and reduces debugging capabilities.”
Although IN25COB2 r9.1 will continue to successfully process the listing and add it to the PROTSYM file if the optimization options are turned on, in order to prevent or minimize these inconsistencies, OPTIMIZE(0) and NOSTGOPT are now required compile options when compiling programs with Enterprise Cobol v5 and above.
Please refer to the required Cobol compile options for use with IN25COB2 found in either the Symbolic Support section of the CA InterTest and Symdump documentation wiki or the CA Application Quality and Testing Tools r9.1 Symbolic Guide.
Detailed information on the OPTIMIZE and STGOPT/NOSTGOPT compile options can be found in the v5.1, v5.2, or v6.1 IBM Enterprise Cobol Programming Guides.