[PATCH] C undefined behavior fix

Gérard Roudier groudier@free.fr
Wed Jan 9 12:20:00 GMT 2002



On Tue, 8 Jan 2002, J.A. Magallon wrote:

>
> On 20020107 jtv wrote:
> >
> >Let's say we have this simplified version of the problem:
> >
> >	int a = 3;
> >	{
> >		volatile int b = 10;
>
>     >>>>>>>>> here b changes

Hmmm...
Then your hardware is probably broken or may-be you are dreaming. :-)

There is nothing in this code that requires the compiler to allocate
memory for 'b'. You just invent the volatile constant concept. :)

> >		a += b;
> >	}
> >
> >Is there really language in the Standard preventing the compiler from
> >constant-folding this code to "int a = 13;"?

Gérard.



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