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c - Casting a pointer does not produce an lvalue. Why?

After posting one of my most controversial answers here, I dare to ask a few questions and eventually fill some gaps in my knowledge.

Why isn't an expression of the kind ((type_t *) x) considered a valid lvalue, assuming that x itself is a pointer and an lvalue, not just some expression?

I know many will say "the standard disallows it", but from a logical standpoint it seems reasonable. What is the reason that the standard disallows it? After all, any two pointers are of the same size and the pointer type is just a compile-time abstraction that indicates the appropriate offset that should be applied when doing pointer arithmetic.

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The result of a cast is never an lvalue by itself. But *((type_t *) x) is an lvalue.


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