/sys$common/syshlp/helplib.hlb MACRO, /MIGRATION, Qualifiers, /ENABLE  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /ENABLE=(option[,...])
       /NOENABLE

    Provides initial settings for the compiler functions that can be
    controlled by the .DISABLE and .ENABLE MACRO directives.

    You can specify one or more of the following functions:

    Option      Description

    DEBUG       Includes local symbol table information in
                the object file for use with the debugger.
                If the /DEBUG qualifier is also specified,
                it overrides /ENABLE=(DEBUG,TRACEBACK) or
                /DISABLE=(DEBUG,TRACEBACK), regardless of their order
                on the command line.
    FLAGGING    Activates compiler flagging.
    GLOBAL      Assumes undefined symbols are external symbols.
    OVERFLOW    Activates production of overflow trap code for the
                following opcodes: ADDx, ADWC, INCx, ADAWI, SUBx,
                SBWC, DECx, MNEGx, MULx, CVTxy (where x is greater
                than y, for example CVTLB), AOBxx, ACBL, and SOBxx.
    QUADWORD    Provides support for quadword literal and address
                expressions.
    SUPPRESSION Provides listing of unreferenced symbols in the
                symbol table.
    TRACEBACK   Provides traceback information to the debugger.
                If the /DEBUG qualifier is also specified,
                it overrides /ENABLE=(DEBUG,TRACEBACK) or
                /DISABLE=(DEBUG,TRACEBACK), regardless of their order
                on the command line.

    By default, at compiler activation, FLAGGING, GLOBAL, TRACEBACK,
    and SUPPRESSION are enabled, and DEBUG, OVERFLOW, and QUADWORD
    are disabled.

    The /NOENABLE qualifier has the same effect as not specifying the
    /ENABLE qualifier. It can also be used to negate the effects of
    any /ENABLE qualifiers specified earlier in the command line.

                                   NOTE

       For every option of the /ENABLE qualifier, if /ENABLE and
       /DISABLE are used in the same command line for the same
       option, /DISABLE will always prevail, regardless of its
       position in the command line.

       You may want to enable an option previously disabled through
       the use of a symbol. For example, you may have incorporated
       the following frequently used options into the DCL symbol
       MAC, as follows:

       MAC::== MACRO/MIGRATION/NOTIE/DISABLE=FLAGGING

       To enable FLAGGING using the symbol MAC, issue the following
       command:

       $ MAC /NODISABLE/ENABLE=FLAGGING