Re: [PATCH] fat sparse fixes

[Linus Torvalds]

On Mon, 29 Sep 2003 Andries.Brouwer@xxxxxx wrote:
>
> --- a/fs/fat/dir.c	Mon Sep 29 01:05:41 2003
> +++ b/fs/fat/dir.c	Mon Sep 29 01:11:39 2003
> @@ -630,7 +630,7 @@
>  		    put_user(slen, &d1->d_reclen))
>  			goto efault;
>  	} else {
> -		if (put_user(0, d2->d_name)			||
> +		if (put_user(0, d2->d_name+0)			||
>  		    put_user(0, &d2->d_reclen)			||
>  		    copy_to_user(d1->d_name, name, len)		||
>  		    put_user(0, d1->d_name+len)			||

The above seems to just work around a sparse bug. Please don't - I'd 
rather have regular code and try to fix the sparse problem.

Hmm.. I wonder why sparse doesn't get the address space right on arrays. 
It should see that "d2" is a user pointer , so d2->d_name is one too.

It gets it right if you add the "+0", or if you add a "&" in front. So 
it looks like the sparse array->pointer degeneration misses something.

		Linus

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