Section 8,4,1: Bit

 A bit constant is a binary, octal, or hexadecimal constant.  You
 can use this type of constant wherever numeric constants are
 allowed and it assumes a numeric data type according to its
 context.

 A binary constant has the form:

   'c1c2c3...cn'B      c is a 0 or 1

 An octal constant has the form:

   'c1c2c3...cn'O      c is a digit in the range 0 - 7

 A hexadecimal constant has the form:

   'c1c2c3...cn'X      c is a digit in the range 0 - 9, or a letter
         or            in the range A - F, or a - f
   'c1c2c3...cn'Z

 Bit constants are "typeless" numeric constants.  They assume data
 types based on their usage, according to the following rules:

  o  When the constant is used with a binary operator, including the
     assignment operator, the data type of the constant is the data
     type of the other operand.

  o  When a specific data type is required, that type is assumed for
     the constant.

  o  When the constant is used as an actual argument, if the bit
     constant is greater than 4 bytes, INTEGER*8 is assumed;
     otherwise, INTEGER*4 is assumed.

  o  When the constant is used in any other context, an INTEGER*4
     data type is assumed (unless the -noi4 or -i8 (AXP only)
     compiler option specifies otherwise).