o  Throughout these notes, the term VSI BASIC or the name BASIC
       used alone, applies to VSI BASIC for OpenVMS I64 Systems, HP
       BASIC for OpenVMS Alpha Systems, and HP BASIC for OpenVMS VAX
       Systems. The following terms refer to information that applies
       specifically to the corresponding product.

          I64 BASIC  -  VSI BASIC for OpenVMS I64 Systems
          Alpha BASIC  -  HP BASIC for OpenVMS Alpha Systems
          VAX BASIC  -  HP BASIC for OpenVMS VAX Systems

    o  I64 BASIC V1.8-004 minimally requires OpenVMS I64 Version
       8.4-1H1 to run.

    o  The default data type for I64 BASIC is IEEE S_floating point
       whereas for Alpha BASIC and VAX BASIC the default is VAX F_
       floating point. To continue use of the VAX floating point data
       types you must use the /REAL_SIZE={SINGLE | DOUBLE | GFLOAT}
       qualifier, or the OPTION SIZE=REAL {SINGLE | DOUBLE | GFLOAT}
       statement.

       Since the VAX floating point data types are not available
       in the Itanium hardware, they are supported by converting
       the values to an appropriate IEEE data type, performing
       the calculation, and then converting the values back to VAX
       floating point data type. This process can cause rounding
       errors and the results to differ slightly from those obtained
       using VAX floating point directly.

       Note that constants in programs are represented in the
       default floating point data type unless explicitly specified
       otherwise, and they may be subject to conversion to IEEE data
       types.

       See the white paper, "OpenVMS floating-point arithmetic on the
       Intel[R] Itanium[R] architecture" at
       http://www.hp.com/products1/evolution/alpha_retaintrust/download/i64-floating-pt-wp.pdf
       for more information.

    o  By default, programs are compiled at optimization level 4
       (/OPT=LEVEL=4), the highest level of optimization. If you
       encounter problems with the generated code, try compiling the
       program with a lower level of optimization. This may correct
       the problem. Please report any problems to HP, even if the
       program works correctly at a lower optimization level.