DDK's C compiler ought to conform a bit better

Tech-Archive recommends: Fix windows errors by optimizing your registry

C standard page 81 footnote 85:
A cast does not yield an lvalue.
Of course I would prefer if the standard would state that rule normatively instead of advisorily, but the committee's intention is clear.

Page 91 section 6.5.16 applies to all kinds of assignment operators: 
Constraints
An assignment operator shall have a modifiable lvalue as its left operand.

Conforming C implementations are required to issue at least one diagnostic when given a translation unit containing the following:
ULONG x = 8; // OK
(ULONG)x |= 3; // violation of a constraint

OK, sure the DDK's C compiler isn't a real C compiler. But why ignore something like this? For example suppose the declaration of x were actually a ULONG_PTR and just happened by accident to map onto a ULONG, while the cast is still a ULONG? As a matter of fact that's exactly the situation where I saw it. Why not issue a warning? 

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