Conversions outside of the essential type categories

[gdavis]

Hello,

With respect to the essential type rules, do conversions to types that are outside the essential type categories count as violations of the rules? For example:

Code:

#include
char buf[80];
char *p = buf;
uintptr_t p_plus_one;
void foo(void);
void foo(void) {
    // This next statement violates R11.4.  But does
    // it violate R10.8?  As a pointer type, p+1 does not
    // have a clear essential type category.
    p_plus_one = (uintptr_t)(p+1);
}

On the one hand, the spirit of the rule seems like it should prohibit such things. On the other hand, TC1 amends rule 10.1 to describe how a pointer type may not be used as an operand of a logical operator.

Thank you for your time.

-Greg