[PATCH v1] libio: Use NULL instead of 0 as a null pointer constant

[Maciej W. Rozycki]

On Tue, 17 Dec 2024, Alejandro Colomar wrote:

> This was missed in a recent global change.
> 
> Fixes: 53fcdf5f743a (2024-11-25, "Silence most -Wzero-as-null-pointer-constant diagnostics")
> Reported-by: "Maciej W. Rozycki" <macro@redhat.com>
> Cc: Siddhesh Poyarekar <siddhesh@sourceware.org>
> Cc: Bruno Haible <bruno@clisp.org>
> Cc: Martin Uecker <uecker@tugraz.at>
> Cc: Xi Ruoyao <xry111@xry111.site>
> Cc: Florian Weimer <fweimer@redhat.com>
> Cc: Joseph Myers <josmyers@redhat.com>
> Signed-off-by: Alejandro Colomar <alx@kernel.org>
> ---

 Thank you, this change looks good to me.

Reviewed-by: Maciej W. Rozycki <macro@redhat.com>

> diff --git a/libio/libioP.h b/libio/libioP.h
> index 34bf91fcd8..70e2bdfc9d 100644
> --- a/libio/libioP.h
> +++ b/libio/libioP.h
> @@ -910,7 +910,8 @@ extern int _IO_vscanf (const char *, va_list) __THROW;
>  # ifdef _IO_USE_OLD_IO_FILE
>  #  define FILEBUF_LITERAL(CHAIN, FLAGS, FD, WDP) \
>         { _IO_MAGIC+_IO_LINKED+_IO_IS_FILEBUF+FLAGS, \
> -	 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, (FILE *) CHAIN, FD, \
> +	 NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, \
> +	 NULL, NULL, (FILE *) CHAIN, FD, \

 OK, this matches commit 53fcdf5f743a.

> @@ -924,14 +925,16 @@ extern int _IO_vscanf (const char *, va_list) __THROW;
>  # ifdef _IO_USE_OLD_IO_FILE
>  #  define FILEBUF_LITERAL(CHAIN, FLAGS, FD, WDP) \
>         { _IO_MAGIC+_IO_LINKED+_IO_IS_FILEBUF+FLAGS, \
> -	 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, (FILE *) CHAIN, FD, \
> +	 NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, \
> +	 NULL, NULL, (FILE *) CHAIN, FD, \
>  	 0, _IO_pos_BAD }
>  # else
>  #  define FILEBUF_LITERAL(CHAIN, FLAGS, FD, WDP) \
>         { _IO_MAGIC+_IO_LINKED+_IO_IS_FILEBUF+FLAGS, \
> -	 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, (FILE *) CHAIN, FD, \
> +	 NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, \
> +	 NULL, NULL, (FILE *) CHAIN, FD, \
>  	 0, _IO_pos_BAD, 0, 0, { 0 }, 0, _IO_pos_BAD, \
> -	 NULL, WDP, 0 }
> +	 NULL, WDP, NULL }

 OK, likewise.

 I have verified this to build without warnings for the `mips-linux-gnu' 
target too.

  Maciej