Specifying assembler options in the source program

Process (*PROCESS) statements let you specify selected assembler options in the assembler source program. You can include them in the primary input data set or provide them from a SOURCE user exit.

You can specify a maximum of 10 process statements in one assembly. After processing 10 process statements, the assembler treats the next input record as an ordinary assembler statement; in addition the assembler treats further process statements as comment statements. You cannot continue a process statement from one statement to the next.

When the assembler detects an error in a process statement, it produces one or more warning messages. If the installation default option PESTOP is set, then the assembler stops after it finishes processing any process statements. If the keyword OVERRIDE is added to a process statement, then the nominated assembler option is not overridden by specifications at a lower level of precedence. If the specified option is not accepted on a process statement and a different value has been supplied as an invocation or input file option, the option is not accepted and a warning message is issued.

The ACONTROL instruction lets you specify selected assembler options anywhere through the assembler source program, rather than at the beginning of the source (as provided by *PROCESS statements).

The assembler recognizes the assembler options in the following order of precedence (highest to lowest):
  1. Fixed installation defaults
  2. Options on *PROCESS OVERRIDE statements
  3. Options in the External File (z/OS® and CMS) or Library member (z/VSE®)
  4. Options on the PARM parameter of the JCL EXEC statement under z/OS and z/VSE or the High Level Assembler command under CMS
  5. Options on the JCL OPTION statement (z/VSE only)
  6. Options specified via the STDOPT (Standard JCL Options) command (z/VSE)
  7. Options on *PROCESS statements
  8. Non-fixed installation defaults

Options specified by the ACONTROL instruction take effect when the specifying ACONTROL instruction is encountered during the assembly. An option specified by an ACONTROL instruction may override an option specified at the start of the assembly.

The assembler lists the options specified in process statements in the High Level Assembler Option Summary section of the assembler listing.

Process statements are also shown as comment lines in the source and object section of the assembler listing.