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Date: Sat, 6 Sep 2003 02:46:14 -0700
From: Marcel Moolenaar <marcel@xcllnt.net>
To: Alexander Leidinger <Alexander@Leidinger.net>
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cc: Dan Nelson <dnelson@allantgroup.com>
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Subject: Re: Question about genassym, locore.s and 0-sized
	arrays(showstopper for  an icc compiled kernel)
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On Sat, Sep 06, 2003 at 10:57:52AM +0200, Alexander Leidinger wrote:
> 
> ---snip---
> % <marcel.c   
> #include <stdio.h>
> 
> struct foo {
>         int tag;
>         char obj[];
> };
> 
> int main(void) {
>         struct foo bar;
> 
>         printf("%d\n", sizeof(struct foo));
>         printf("%d\n", sizeof(bar));
> 
>         return 0;
> }
> 
> % ./a.out     
> 4
> 4
> ---snip---

The compiler seems to behave correctly WRT C99. However, when
presented with code that uses extensions the compiler behaves
inconsistently or erratically. If the compiler cannot do any-
thing useful with zero-sized arrays, it should reject them
completely. Only then can one reasonably fall back on C99 to
explain the behaviour of the compiler. However, since the
compiler accepts zero-sized arrays, it is already in violation
with C99 and one cannot use C99 as a basis to explain the
any behaviour of the compiler in the context of the non-compliant
construct. The creation of single-element array instead of
the declared zero-element array is downright broken.

My $0.02

-- 
 Marcel Moolenaar	  USPA: A-39004		 marcel@xcllnt.net