[U-Boot] [PATCH 3/3 v2] Replace CONFIG_SYS_GBL_DATA_SIZE by auto-generated value

[Wolfgang Denk]

Dear Alessandro Rubini,

In message <20101026211821.GA2528 at morgana.i.gnudd.com> you wrote:
> > Is it guaranteed (I mean by the C standard) that the alignment of a
> > struct (which affects only the possible start address) also has effect
> > on the sizeof() for that struct, in the sense that sizeof() is
> > guaranteed to be a multiple of that alignment requirement?
> 
> Yes. Because if you make an array, all of them must be aligned, and
> the size of an array is a multiple of sizeof(array_item).  While
> alignment is not in the standard, the sizeof/array relationship is.

I am not convinced, as we don't have an array context here.

> It's in C99 draft (http://busybox.net/~landley/c99-draft.html)
> 
>       6.5.3.4 The sizeof operator
> 
>       #6
> 
>       EXAMPLE 2 Another use of the sizeof operator is to compute the
>       number of elements in an array:
>         sizeof array / sizeof array[0]

I don't see that with

	struct foo x;
	struct foo y[N];

we have a guarantee that sizeof(x) == sizeof(y[0]). 

Maybe I'm just paranoid...

Best regards,

Wolfgang Denk

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