D=/USAGE=(EMPTY,PACKED,UNSUP,UNINIT) (OpenVMS VAX)
                                   D=/USAGE=(EMPTY,PACKED,UNSUP,UNINIT,VOLATILE) (OpenVMS Alpha)
                                   D=/USAGE=(EMPTY,PACKED,UNSUP,UNINIT,VOLATILE) (OpenVMS I64)
  /NOUSAGE

  Directs the compiler to perform compile-time checks indicated by
  the   chosen   options.   A  single  identifier  or  a  list  of
  identifiers enclosed in parentheses  may  follow  /USAGE;  these
  identifiers  are  options that tell the compiler which checks to
  perform.  The options are as follows:

     ALL
       Enables checking of all options.

     NONE
       Disables all /USAGE options.

     [NO]EMPTY_RECORDS
       Checks for fetching records with no fields. Such fields are
       usually created by the %DICTIONARY directive for unsupported data
       types.

     [NO]NONGRNACC
       Detects  code for which the compiler cannot generate requested
       granularity.

     [NO]PACKED_ACTUALS
       Checks for passing components of packed structures to VAR
       parameters.

     [NO]PERFORMANCE
       Checks for declarations and uses that will result in less than
       optimal performance.

     [NO]UNCERTAIN
       Checks for variables that may be uninitialized depending on
       program flow.

     [NO]UNINITIALIZED
       Checks for variables that are known to be uninitialized.

     [NO]UNSUPPORTED_CDD
       Checks for usage of CDD/Repository constructs that do not
       correspond to VSI Pascal data types.

     [NO]UNUSED
       Checks for variables that are declared but never referenced.

     [NO]UNCALLABLE
       Checks for routines that are declared but never referenced.
       (OpenVMS Alpha and OpenVMS I64 only)

     [NO]VOLATILE
       Checks for accesses to volatile data that cannot be protected as
       atomic operations. (OpenVMS Alpha and OpenVMS I64 only)

  See the "HP Pascal Language  Reference  Supplement  for  OpenVMS
  Systems"  for  a  list  of  the  types of variables that are not
  checked for uninitialization.

  By  default  on  OpenVMS  VAX  systems,   /USAGE=(EMPTY_RECORDS,
  PACKED_ACTUALS,  UNSUPPORTED_CDD, UNINITIALIZED) is enabled.  By
  default   on   OpenVMS   Alpha   and   OpenVMS   I64    systems,
  /USAGE=(EMPTY_RECORDS,         NONGRNACC,        PACKED_ACTUALS,
  UNSUPPORTED_CDD, UNINITIALIZED, VOLATILE)  is  enabled.   /USAGE
  without  options  is  equivalent  to  /USAGE =ALL.  The negation
  /NOUSAGE is equivalent to /USAGE=NONE.