SUBSCRBOUNDS

Message        <Context> an array is being accessed outside the
               bounds specified for the array type.

Description    The compiler has detected an array access that is
               outside the bounds of the array.  The array access
               might cause unpredictable behavior.  Note that in C,
               an array is declared using the number of elements,
               but the first element has subscript 0.  It is a
               common coding error to attempt to access the last
               element of an array of "n" elements using a subscript
               of "n" instead of "n - 1".  However, there are two
               common practices that intentionally employ
               out-of-bounds subscripts to useful/correct effects
               that are not reported by this message, but have
               separate optional messages.  First, taking the
               address of an array element that is exactly one
               beyond the last element of an array is completely
               valid in standard C as long as the address is not
               used to access memory.  The optional subscrbounds2
               message can be enabled to report taking the address
               of the array element exactly one beyond the last
               element.  Second, it is a somewhat common practice to
               declare the last member of a struct as an array with
               one element, and then allocate such structs at
               runtime with different sizes, recording the actual
               size in an earlier member of the struct.  The
               optional subscrbounds1 message can be enabled to
               report subscripts greater than zero applied to arrays
               declared with only one element.

User Action    Specify an array subscript that is within the bounds
               of the array type.