This procedure gathers the diagnostic information required for developing a keyword string to search the software support database. It describes options that supply all available diagnostic information. You will need this information to discuss the problem with your IBM support representative if a search against the database fails to locate a fix for your problem.

1. Determine if the program has been changed since it was last assembled successfully. If it has, examine the changes. If the error is occurring in the changed code and cannot be corrected, note the change that caused the error. If possible, retain copies of both the original and the changed programs to submit with an Authorized Program Analysis Report (APAR) if it is required.
2. Ensure that you are assembling the correct version of the source code. You might have incorrectly identified the location of your source file. For example, check your data set names.
3. Determine if the problem looks like a wait or a loop. If it does, it might be a system problem. You should follow your installation's procedures for resolving such problems.
4. Follow the basic diagnostic procedures discussed in HLASM Programmer's Guide. If you receive an assembler error diagnostic message, you should verify the correct syntax and usage of the code that produced the error.
5. Correct all problems diagnosed by diagnostic messages, and make sure that previous diagnostic messages are not the cause of the current problem. Pay attention to warning messages (W-level messages). Identify the message by the following convention:
   • High Level Assembler messages are prefixed by the characters ASMA.
   • For messages with prefixes other than ASMA, the prefix determines which system/subsystem issued the message. Consult the applicable system/subsystem messages manual.
6. Your installation may have received an IBM Program Temporary Fix (PTF) for the problem. Make sure that all PTFs have been applied, so that your installation is at the latest maintenance level.
7. The Preventive Service Plan (PSP bucket), an online database available to IBM customers, gives information about product installation problems and other problems. Refer to the appropriate service planning section for your platform for more information:
   • Preventive Service Planning for z/OS
   • Preventive Service Planning for z/VM
   • Preventive Service Planning for z/VSE
   For the relevant information for the HLASM Toolkit Feature, see the HLASM Toolkit Feature Installation and Customization Guide.
8. After the failure has been identified, consider writing a small test case that reproduces the problem. This test case should help you to:
   • Isolate the problem.
   • Distinguish between an error in the application program and an error in High Level Assembler.
   • Choose keywords that best describe the error.
9. Specify the following assembler options, in addition to the options originally specified, and reassemble the program. These options produce maximum diagnostic information that help you diagnose product errors. See theHLASM Programmer's Guide for more information about how to use these options.
   • DXREF
   • ESD
   • FLAG(0,ALIGN,CONT,RECORD,SUBSTR)
   • LIST(121)
   • MXREF(FULL)
   • PCONTROL(DATA,GEN,ON,MCALL,MSOURCE,UHEAD)
   • RLD
   • RXREF
   • USING(MAP,WARN(15))
   • XREF(FULL)
10. If the error symptoms change, return to step 4.
11. Record the sequence of events that led to the error condition. You might be able to use this information in developing a keyword string, and will need it if an APAR is required.
12. Begin developing the keyword string, using the procedure in Building a keyword string.