Re: [PATCH 2/3 V2] Do not include stdio.h in libgcc's Decimal/Float128 conversions.

[Segher Boessenkool <segher@kernel.crashing.org>]

On Mon, Mar 01, 2021 at 12:18:52PM -0500, Michael Meissner wrote:
> The _sprintfkf.c file was including stdio.h to get the definition of sprintf.

(declaration of)

> This patch modifies this so that stdio.h is not included in order to support
> freestanding cross compilers that might not provide stdio.h.

So the code cannot work at all there?  Will not link?

> +   We use __builtin_sprintf so that we don't have to include stdio.h to define
> +   sprintf.  Stdio.h might not be present for freestanding cross compilers that
> +   do not need to include a library.  */

"declare sprintf", and the function is called stdio.g (all lowercase).
It is often written <stdio.h>, which makes it easier to handle in
sentences.

> @@ -54,5 +57,5 @@ int __sprintfkf (char *restrict string,
>    if (__sprintfieee128)
>      return __sprintfieee128 (string, format, number);
>  
> -  return sprintf (string, format, (long double) number);
> +  return __builtin_sprintf (string, format, (long double) number);

sprintf as well as __builtin_sprintf do not exist exactly when <stdio.h>
does not (or are not guaranteed to exist, anyway).


Segher