Undefined behaviours in D and C

[Walter Bright]

BCS wrote:
> Currently the described code is legal, unsafe (it can result in invalid 
> pointers) and has undefined semantics (it can result in unpredictable, 
> implementation defined results). What I think bearophile wants is for 
> only the last to be changed, that is; you can still do things that 
> result in invalid pointers, but it does so in a well defined way (at 
> least with regards to the bit pattern the pointer ends up as)

I don't think that's a useful thing to specify - where's the advantage, 
and if D is on a machine that does pointers differently, why make it 
impossible to port standard D to it?