Question on Abend Analysis and Compiler Listing...

cybertaurean · New User Joined: 22 Dec 2008 Posts: 87 Location: US

Hi All,

Given below is a typical abend message -

+IDI0002I Module XXXXXXXX, program XXXXXXXX, offset X'EA4': Abend UXXXX (I believe this is the memory location that points to the section of code that was active. Is there concept like IP - Instruction Pointer, Frame Pointer, Stack Pointer etc. in mainframe?. Let me know if there is any documentation available on this. I am trying to relate it with Base in Windows which is usually 0X40000000).

In case we don't have the listing available for the code ABC, can I convert the offset to a location in the compiler listing, ABC.LST for the module (I can get the LST file from CHGMAN).

The abend UXXXX could happen at multiple locations in the module. This would help me know where it happened (I'm not sure about this statement since the X'EA4' shown would be the location where the abend routine got executed. This would not be sufficient to know from which part of the code and under what condition, the abend routine was called).

Bottomline, Is there any way to analyze in case there is no LISTING available for the module?.

Regards,
Sumesh

Robert Sample · Posted: Wed Apr 21, 2010 4:33 pm

You need to learn the concept of PSW (Program Status Word) and the fields within it. You also need to go to www.redbooks.ibm.com and find manual SG24-7110, z/OS Diagnostic Data Collection and Analysis and read this manual.

It may be possible to debug the program without a listing but the listing makes it much easier.

cybertaurean · New User Joined: 22 Dec 2008 Posts: 87 Location: US

Thanks a lot Robert!!!. I got the book. Will try to learn it

.

William Thompson · Posted: Wed Apr 21, 2010 7:21 pm

cybertaurean · New User Joined: 22 Dec 2008 Posts: 87 Location: US

Hi William,

I didn't quite understand what you were trying to convey (guess I didn't catch the lighter side of it

). Could you let me know how it is possible to backtrack the flow ?

Prog A

if A
else
call abend_routine

if B
else
call abend_routine

if C
else
call abend_routine
.
.
.

abend_routine (could be an assembler piece as shown below) -
PRGDUMP CSECT
SAVE (14,12)
BALR 11,0
USING *,11
ABEND XXXX,DUMP
END

In the above module, if we don't have compiler listing, it would just show the offset in prog A where the PRGDUMP got called?.

Now, with the data above, how can we know where exactly the call came from (backtracking) without the listing available?

Regards,
Sumesh

Kjeld · Posted: Thu Apr 22, 2010 12:01 pm

In Sumesh's example, I will find it hard to do without a listing. You can do it by location the working storage data involved in the abended instruction.

But, if it is a programmed (intentional) abend, the programmer should have documented the condition and data that lead to the decision to abend the programme.

enrico-sorichetti · Posted: Thu Apr 22, 2010 12:17 pm

enrico-sorichetti · Posted: Thu Apr 22, 2010 12:43 pm

dick scherrer · Posted: Thu Apr 22, 2010 7:23 pm

Hello,

If there are 3 different situations that could cause a user abend, there should be 3 different user abend values. . .

If there are 3 different situations that are permitted to cause the same user abend then there should be an additional working-storage entry that contains the information as to why the abend was caused. Before the ws entry that describes the abend, it helps to add an "eyecatcher" so that when looking at a dump, something "readable" is always there.

cybertaurean · New User Joined: 22 Dec 2008 Posts: 87 Location: US

Thanks everyone for the replies :-)

@enrico

The listing I referred to is the LST file that is interpreted through CHGMAN. I think this gets created even if you havent provided LIST in Compile Option (not sure).

What I meant by "no listing" is that, since the module was not compiled with LST option, I will not have a listing for the particular module when it abends.

@dick

that should ideally be the case to understand based on any indicator set according to the location from which the abend routine was called. Unfortunately, this is not the case for me.

However, say I had an code C that would be 1, 2 or 3 according to the location, how will I know what is in C if I dont have a listing for the module at all?.

Regards,
Sumesh

enrico-sorichetti · Posted: Thu Apr 22, 2010 9:41 pm

We are just wasting time here!
if a Compiler and Linkage editor listings are not available
the chances for a reasonable debugging are close to 0

review You organization practices in order to have the proper info available at all time.

Furthermore if compile and linkage editor listing are not available Your organization
might not pass any reasonable audit ( seen it, done it )

William Thompson · Posted: Thu Apr 22, 2010 9:52 pm

dick scherrer · Posted: Thu Apr 22, 2010 10:04 pm

Hello,

cybertaurean · New User Joined: 22 Dec 2008 Posts: 87 Location: US

Thanks everyone for the replies...

@enrico
The audit passed is the reason why the module is live. I guess we will have to reinstall using LIST option

.

@william
I got a long way to go to reach your expertise

. Guess, I will have to study assemblers now. However, is that enough?. Will I have to learn the architecture, addressing etc. besides learning assembler?

@dick
I had a walkthrough of the code and found that I am not completely lost here. I happened to find two values ABEND-PARAGRAPH and ABEND-STATUS. I located the BLW's for these fields and searched the hex-dump in Fault Analyzer and VOILA!!! I got the values. The abend was due to a missing segment (will analyze further to find the reason why this segment was not present;that's another story).

Bottomline is that I'm quite happy that I decided to stretch a bit and subsequently learned more.

Regards,
Sumesh

dick scherrer · Posted: Fri Apr 23, 2010 7:14 pm

Good to hear you found the problem