On Mon, 2017-07-17 at 10:30 -0500, Gustavo A. R. Silva wrote:
> Remove unnecessary static on local variable ops.
> Such variable is initialized before being used,
> on every execution path throughout the function.
> The static has no benefit and, removing it reduces
> the code size.
[]
> In the following log you can see the difference in the code size. Also,
> there is a significant difference in the bss segment. This log is the
> output of the size command, before and after the code change:
> 
> before:
>    text    data     bss     dec     hex filename
>    3211     680      64    3955     f73 sound/soc/sh/rcar/ssiu.o
> 
> after:
>    text    data     bss     dec     hex filename
>    3207     592       0    3799     ed7 sound/soc/sh/rcar/ssiu.o
[]
> diff --git a/sound/soc/sh/rcar/ssiu.c b/sound/soc/sh/rcar/ssiu.c
[]
> @@ -250,7 +250,7 @@ int rsnd_ssiu_probe(struct rsnd_priv *priv)
>  {
>       struct device *dev = rsnd_priv_to_dev(priv);
>       struct rsnd_ssiu *ssiu;
> -     static struct rsnd_mod_ops *ops;
> +     struct rsnd_mod_ops *ops;
>       int i, nr, ret;
>  
>       /* same number to SSI */

I'm not an sh user anymore, but it's curious to me why
the static removal has such a large impact on data size.

Is this for an allyesconfig with debug symbols?

btw: this does compile for x86 and those sizes seem
     more sensible.

$ size sound/soc/sh/rcar/ssiu.o*   text    data     bss     dec     hex filename
   1950     248       0    2198     896 sound/soc/sh/rcar/ssiu.o.defconfig.new
   1950     248       8    2206     89e sound/soc/sh/rcar/ssiu.o.defconfig.old
   2692     248       0    2940     b7c 
sound/soc/sh/rcar/ssiu.o.allyesconfig.new
   2692     248       8    2948     b84 
sound/soc/sh/rcar/ssiu.o.allyesconfig.old


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