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Re: Help with bit-field semantics in C and C++


[ here E is a four-valued enum, 0,1,2,3 ]

On Tue, Aug 24, 2004 at 04:09:02PM -0700, Mike Stump wrote:
> (E)n, where n is an int with value, say of 7, is permitted by the 
> standard to take on the value 7.  This is because the text of the 
> standard says the value is unspecified.  7 is a unspecified value, 
> honest.

I agree with you so far; (E)n might be 7.

The next question, then, is whether, despite this, a compiler is allowed
to implement a switch on a variable of type E as a jump table, in such a
way that a value outside of [0,3] malfunctions (jumps to a random address).

Let's leave to one side whether this is a good idea.  Is it permitted?



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