PH30060: ASMA951U AFTER OPSYN CHANGES INSTRUCTION USED IN MACRO

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• If OPSYN changes a model instruction in a macro definition to an
  instruction which is not allowed to be generated (as listed for
   message ASMA001E) this can cause ASMA951U or other errors.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: Users of HLASM for z/OS, z/VM, z/VSE and     *
  *                 Linux                                        *
  ****************************************************************
  * PROBLEM DESCRIPTION: If OPSYN changes a model instruction    *
  *                      in a macro definition to an             *
  *                      instruction which is not allowed to     *
  *                      be generated this can cause ASMA951U    *
  *                      or other errors. This fix corrects      *
  *                      this issue.                             *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  When a macro is defined, various assembler instructions are
  recognized as part of the macro and encoded during definition,
  and all other instructions are saved as model statements, which
  will be used to generate machine or assembler instructions when
  the macro is invoked.
  
  Generation of a model statement must not result in attempting
  to generate a restricted instruction that should have been
  encoded when the macro was defined, as this cannot be handled
  at macro generation time.  There is therefore a check at macro
  generation time to reject any restricted instruction with
  message ASMA001E.
  
  This check was only being performed if the operation code was
  generated by variable substitution, as it was assumed that any
  other operation code would have been checked when the macro was
  defined.  However, the meaning of an operation code can be
  redefined by the OPSYN instruction, which can assign the current
  function of one operation code to another operation code, making
  the redefined operation code a new name for the function of the
  existing instruction.
  
  If the operation code was changed using OPSYN after the macro
  was defined, making it a restricted instruction, this bypassed
  the ASMA001E check.  In most cases, this would cause termination
  of the assembler with message ASMA951U because the assembler
  instruction type did not map to a supported operation.  As a
  special case, if the instruction was changed to a synonym of
  REPRO, this caused an attempt to copy the next line to the
  object code file, but it was not in the correct format for
  REPRO, producing incorrect results.
  

Problem conclusion

• The check for restricted instructions is now performed even when
  the operation code does not include a variable.  This means that
  message ASMA001E will be issued if OPSYN is used to change a
  model instruction to a restricted instruction as listed for this
  message.
  
  During testing it was noted that two instructions CATTR and
  ALIAS had been incorrectly marked as restricted, so they were
  previously rejected with message ASMA001E if the operation code
  was created by variable substitution.  This has been corrected.
  

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:

  UI71966 UI71967 UI71968

Modules/Macros

•    ASMAINFO ASMA1L   ASMA1R   ASMA5UNI ASMA9Z
  

Fix information

• Fixed component name

  HLASM MVS, VM &

• Fixed component ID

  569623400

Applicable component levels

• R160 PSY UI71967

     UP20/10/08 P F010

• R360 PSY UI71966

     UP20/10/07 P 2010

• R689 PSY UI71968

     UP20/10/07 I 1000

Fix is available

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