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Re: Should structure with flexible array be allowed to be passed by value?
On Wed, 25 Mar 2009, H.J. Lu wrote:
> gcc.c-torture/compile/pr16566-2.c has
>
> ---
> struct A
> {
> int i;
> int x[];
> };
>
> int foo(struct A a)
> {
> return (a,a).x[0];
> }
> ---
>
> foo will return a random number. I don't think it should be allowed.
This is a perfectly ordinary case of accessing outside array bounds,
undefined behavior at runtime if the code in question is ever executed but
OK in a program as long as the dereference isn't executed.
--
Joseph S. Myers
joseph@codesourcery.com