[SLOF] [PATCH] libc: The arguments of puts() can be marked as "const"

[Segher Boessenkool]

On Wed, Jul 12, 2017 at 06:53:38AM +0200, Thomas Huth wrote:
> That's kind of ugly. Why not simply:
> 
> diff --git a/slof/paflof.c b/slof/paflof.c
> index 50b4adf..ea3c145 100644
> --- a/slof/paflof.c
> +++ b/slof/paflof.c
> @@ -81,8 +81,8 @@ long engine(int mode, long param_1, long param_2)
>                 LAST_ELEMENT(xt_FORTH_X2d_WORDLIST).a = xt_LASTWORD;
> 
>                 // stack-pointers
> -               dp = the_data_stack - 1;
> -               rp = handler_stack - 1;
> +               dp = the_data_stack;
> +               rp = handler_stack;
> 
>                 // return-address for "evaluate" personality
>                 dummy.a = &&over;

Paflof originally had options to cache 0, 1, or 2 top-of-stack elements.
Now it is always 1; it is usually fastest (2 is theoretically a tiny
bit better, but a bit worse in practice).

There also was a user-space version.  It set up the stacks with unmapped
guard pages, so it could trap stack underflows (and overflows).  If you
run in translation-off mode you of course cannot do such things.

(Your patch is incomplete btw, there are five or six or so places that
need changes).

I would just add a cast to shut up the warning, and not lose the
optimisations (or ignore the warning).


Segher