references to dereferenced null pointers

[Randall Atkinson]

Henry's observation on MSDOS and Doug's comments about the
shortcomings of the Intel architecture are both very well taken.

On at least one such system that I am forced to deal with regularly,
the NULL pointer is internally represented as address F000:0000 hex.
This invariably trips up newcomers to the compiler in question,
which compiler is originally from Washington State (yes, them :-(.