PI48348: ON SIZE ERROR ON A COMPUTE INSTRUCTION

COBOL for AIX Fix Pack 13 (October 2015 PTF) for 4.1.1
COBOL for AIX Fix Pack 14 (August 2016 PTF) for 4.1.1
COBOL for AIX Fix Pack 15 (August 2017 PTF) for 4.1.1
COBOL for AIX Fix Pack 16 (July 2018 PTF) for 4.1.1

APAR status

• Closed as program error.

Error description

• When using the 'on size error' statement with values
  really large, the on size error does not seem to catch it,
  but instead traps at runtime.
  
  ===== COMPILE COMMAND:
  cob2 test.cbl
  
  ===== TESTCASE:
  $ cat test4.cbl
  
         IDENTIFICATION DIVISION.
  
         PROGRAM-ID. 'tst'.
  
         ENVIRONMENT DIVISION.
  
         DATA DIVISION.
  
         WORKING-STORAGE SECTION.
  
  
  
         01 VAR1     PIC 9(18) value 100000000000000000.
  
         01 VAR2     PIC 9(18) value 100000000000000000.
  
         01 VAR3     PIC 9(18).
  
  
  
         PROCEDURE DIVISION.
  
  
  
             COMPUTE VAR3 = VAR1 * VAR2 * 10
  
                  on size error perform erro-overflow.
  
             DISPLAY "VAR3:", VAR3.
  
  
  
             STOP RUN.
  
             EXIT.
  
         erro-overflow.
  
             display "overflow".
  
             stop run.
  
  $
  
  
  With test2.cbl (using smaller values), its fine:
  $ cat test2.cbl
  
         IDENTIFICATION DIVISION.
  
         PROGRAM-ID. 'tst'.
  
         ENVIRONMENT DIVISION.
  
         DATA DIVISION.
  
         WORKING-STORAGE SECTION.
  
  
  
         01 VAR1     PIC 9(18) value 100000000000000.
  
         01 VAR2     PIC 9(18) value 100000000000000.
  
         01 VAR3     PIC 9(18).
  
  
  
         PROCEDURE DIVISION.
  
  
  
             COMPUTE VAR3 = VAR1 * VAR2 * 10
  
                  on size error perform erro-overflow.
  
             DISPLAY "VAR3:", VAR3.
  
  
  
             STOP RUN.
  
             EXIT.
  
         erro-overflow.
  
             display "overflow".
  
             stop run.
  
  $
  
  
  ===== ACTUAL OUTPUT:
  $./a4.out
  <Thread 1>
  <Thread 1>  Traceback:
  <Thread 1>    Offset 0x00000564 in procedure writeERRmsg
  <Thread 1>    Offset 0x00000044 in procedure _iwzWriteERRmsg
  <Thread 1>    Offset 0x00000280 in procedure TST
  <Thread 1>    --- End of call chain ---
  IWZ036W  Truncation of high order digit positions occurred in
  program TST on line number 26.
  
  VAR3:000000000000000000
  
  $
  
  ===== EXPECTED OUTPUT:
  $./a2.out
  overflow
  $
  

Local fix

• N/A
  

Problem summary

• USERS AFFECTED:
  COBOL for AIX clients who use 'on size error' with very large
  values may be affected by this issue.
  
  PROBLEM DESCRIPTION:
  The program will produce an abend instead of catching the
  overflow in size error.
  The compiler was checking for overflow in the MOVE code.  This
  code assumes that if it catches an overflow it should issue an
  error.
  But the MOVE code can be part of a statement with a SIZE ERROR
  phrase (as in this case).
  

Problem conclusion

• The compiler code has been fixed to handle the above mentioned
  case.
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

  PI55304

Fix information

• Fixed component name

  COBOL AIX RUNTI

• Fixed component ID

  5724Z8702

Applicable component levels