PH21000: In some circumstances the optimizer erroneously maps distinct intermediate results to the same compiler temporary variable

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• To reduce memory usage, the optimizer will reuse compiler
  temporary variables. In some cases, such as the result of
  alphanumeric functions in an expression like
  
          if function upper-case(string1(i:1)) =
             function upper-case(string2(i:1))
  
  the same temporary variable is incorrectly used for both
  function instances, with the result that the expression is never
  true.
  

Local fix

• Compile at OPT(0).
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: Users of Enterprise COBOL V6.3 compiling     *
  *                 programs that compare the result of two      *
  *                 FUNCTIONs in the same statement.             *
  ****************************************************************
  * PROBLEM DESCRIPTION: The comparison may always treat the two *
  *                      results as equal.                       *
  ****************************************************************
  * RECOMMENDATION: Apply the provided PTF.                      *
  ****************************************************************
  The compiler initially assigns a unique temporary when a
  FUNCTION produces a result, as well as in many other cases. To
  reduce the overall number of temps, the compiler reuses temps
  that aren't used at the same time in the same statement. When
  mapping temps, the compiler wasn't correctly identifying temps
  used for the result of some FUNCTIONs as being used in the same
  statement.
  

Problem conclusion

• The compiler was fixed to recognize temps used for FUNCTION
  results in the same statement and avoid mapping them to the
  same temp.
  

Temporary fix

Comments

APAR Information

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

  PH20127

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

Modules/Macros

• IGY8RWTU IGYCASMB IGYCCBE  IGYCCCRT IGYCCICS IGYCCSRV IGYCDGEN
  IGYCDIAG IGYCDMAP IGYCEN$0 IGYCEN$1 IGYCEN$2 IGYCEN$3 IGYCEN$4
  IGYCEN$5 IGYCEN$8 IGYCEN$D IGYCEN$R IGYCFGEN IGYCFREE IGYCINIT
  IGYCJA$0 IGYCJA$1 IGYCJA$2 IGYCJA$3 IGYCJA$4 IGYCJA$5 IGYCJA$8
  IGYCJA$D IGYCJA$R IGYCLIBR IGYCLSTR IGYCLVL0 IGYCLVL1 IGYCLVL2
  IGYCLVL3 IGYCLVL8 IGYCMALL IGYCOB2E IGYCOSCN IGYCPGEN IGYCRCTL
  IGYCRDPR IGYCRDSC IGYCREAL IGYCRWT  IGYCSCAN IGYCSIMD IGYCUE$0
  IGYCUE$1 IGYCUE$2 IGYCUE$3 IGYCUE$4 IGYCUE$5 IGYCUE$8 IGYCUE$D
  IGYCUE$R IGYCXREF IGYDRV   IGYEQCWI IGYMSGE  IGYMSGK  IGYMSGT
  IGYQCBE  IGYQSPLT IGYZQEN6 IGYZQENU IGYZQJP6 IGYZQJPN
  

Fix information

• Fixed component name

  ENT COBOL FOR Z

• Fixed component ID

  5655EC600

Applicable component levels

• R630 PSY UI67474

     UP20/01/24 P F001

• R631 PSY UI67475

     UP20/01/24 P F001

• R632 PSY UI67476

     UP20/01/24 P F001

• R63H PSY UI67477

     UP20/01/24 P F001

Fix is available

• Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.