NOOUT,NOOV,POW,NOUN)
  /[NO]CHECK

  Controls whether the compiler performs certain error checking
  during program execution (run time).  The compiler produces extra
  code that performs the checks.

  [NO]ARG_INFO (I64 only)
    Controls whether run-time checking of the actual argument list
    occurs.  For actual arguments that correspond to declared formal
    parameters, the check compares the run-time argument type
    information for arguments passed in registers with the type that
    is expected. An informational message is issued at run time for
    each miscompare. Extra actual arguments or too few actual
    arguments are not reported.

    With the default, NOARG_INFO, no check is made.

  [NO]ARG_TEMP_CREATED
    Controls whether run-time checking occurs for actual arguments
    being copied into temporary storage before routine calls.

    With the default, /CHECK=NOARG_TEMP_CREATED, no check is
    performed.

    When /CHECK=ARG_TEMP_CREATED is specified, if a copy is made at
    run-time, an informative message is displayed.

  [NO]BOUNDS
    Controls whether run-time checking occurs for each dimension of
    an array reference or substring subscript reference to determine
    whether it is within the range of the dimension specified by the
    array or character variable declaration.

    With the default, NOBOUNDS, array bounds checking and substring
    checking do not occur.

  [NO]FORMAT
    Controls whether the run-time message number 61 (FORVARMIS) is
    displayed and halts program execution when the data type for an
    item being formatted for output does not match the format
    descriptor being used (such as a REAL data item with an I
    format).

    The default, FORMAT, causes FORVARMIS to be a fatal error and
    halts program execution.

    Specifying NOFORMAT ignores the format mismatch, which suppresses
    the FORVARMIS error and allows the program to continue.

    If you omit /NOVMS and omit /CHECK=NOFORMAT, the default is
    /CHECK=FORMAT.

    If you specify /NOVMS, the default is NOFORMAT (unless you also
    specify /CHECK=FORMAT).

  [NO]FP_EXCEPTIONS
    Controls whether run-time checking counts each operation that
    generates exceptional values.

    With the default, NOFP_EXCEPTIONS, no run-time messages are
    reported.

    Specifying FP_EXCEPTIONS requests reporting of the first two
    occurrences of each type of exceptional value and a summary
    run-time message at program completion that displays the number
    of times exceptional values occurred.  Consider using
    FP_EXCEPTIONS when the /IEEE_MODE qualifier allows generation of
    exceptional values.

    To limit reporting to only denormalized numbers (and not other
    exceptional numbers), specify UNDERFLOW instead of FP_EXCEPTIONS.

  [NO]FP_MODE (I64 only)
    Controls whether run-time checking of the current state of the
    processor's floating-point status register (FPSR) occurs.  For
    every call of every function or subroutine, the check will
    compare the current state of the FPSR register against the
    expected state.  That state is based on the /FLOAT, /IEEE_MODE and
    /ROUND qualifier values specified by the FORTRAN command.  An
    informational message is issued at run time for miscompares.

    With the default, NOFP_MODE, no check is made.

  [NO]OUTPUT_CONVERSION
    Controls whether run-time message number 63 (OUTCONERR) is
    displayed when format truncation occurs.

    Specifying /CHECK=NOOUTPUT_CONVERSION disables the run-time
    message (number 63) associated with format truncation.  The data
    item is printed with asterisks.

    When OUTPUT_CONVERSION is in effect and a number can not be
    output in the specified format field length without loss of
    significant digits (format truncation), the OUTCONERR (number 63)
    error occurs.

    If you omit /NOVMS and omit /CHECK=NOOUTPUT_CONVERSION, the
    default is OUTPUT_CONVERSION.

    If you specify /NOVMS, the default is NOOUTPUT_CONVERSION (unless
    you also specify /CHECK=OUTPUT_CONVERSION).

  [NO]OVERFLOW
    Controls whether run-time checking occurs for arithmetic overflow
    of all integer calculations.

    Specify OVERFLOW to request integer overflow checking.

    With the default, NOOVERFLOW, overflow checking does not occur.

    Real and complex calculations are always checked for overflow and
    are not affected by /NOCHECK.  Integer exponentiation is
    performed by a routine in the mathematical library.  The routine
    in the mathematical library always checks for overflow, even if
    /CHECK=NOOVERFLOW is specified.

  [NO]POWER
    Suppresses the run-time errors for 0.0**0.0 and
    <negative-value>**<integer-value-of-type-real>,
    so 0.0**0.0 is 1.0 and (-3.0)**3.0 is -27.0.  The default is
    /CHECK=POWER, which causes fatal run-time errors.

  [NO]UNDERFLOW
    Controls whether run-time messages are displayed for floating
    underflow (denormalized numbers) in floating-point calculations.

    Specify UNDERFLOW to request reporting of the first two
    occurrences of denormalized numbers and a summary run-time
    message at program completion that displays the number of times
    denormalized numbers occurred.

    With the default, NOUNDERFLOW, floating underflow messages are
    not displayed.  To check for all exceptional values (not just
    denormalized numbers), specify /CHECK=FP_EXCEPTIONS.

    For more information about exceptional floating-point values and
    exception handling, see the HP Fortran for OpenVMS User Manual.

  ALL
    Requests that all run-time checks (BOUNDS, FORMAT, FP_EXCEPTIONS,
    OUTPUT_CONVERSION, OVERFLOW, and UNDERFLOW) be performed.
    Specifying /CHECK and /CHECK=ALL are equivalent.

  NONE
    Requests no run-time checking.  Specifying /NOCHECK and
    /CHECK=NONE are equivalent.