linux-kernel - Re: [PATCH v4 1/2] system_data

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <3941e130-df05-778b-dc76-90cd58400192@cs.ucla.edu>
Date:   Fri, 2 Oct 2020 09:53:25 -0700
From:   Paul Eggert <eggert@...ucla.edu>
To:     Alejandro Colomar <colomar.6.4.3@...il.com>
Cc:     mtk.manpages@...il.com, linux-man@...r.kernel.org,
        gcc-patches@....gnu.org, libc-alpha@...rceware.org,
        linux-kernel@...r.kernel.org, jwakely.gcc@...il.com,
        David.Laight@...LAB.COM
Subject: Re: [PATCH v4 1/2] system_data_types.7: Add 'void *'

On 10/2/20 8:14 AM, Alejandro Colomar wrote:

> +.I void *

GNU style is a space between "void" and "*", so this should be '.I "void\ *"', 
both here and elsewhere. The backslash prevents a line break.

> +Conversions from and to any other pointer type are done implicitly,
> +not requiring casts at all.
> +Note that this feature prevents any kind of type checking:
> +the programmer should be careful not to cast a

Change "cast" to "convert", since the point is that no cast is needed.

> +.PP
> +The conversion specifier for
> +.I void *
> +for the
> +.BR printf (3)
> +and the
> +.BR scanf (3)
> +families of functions is
> +.BR p ;
> +resulting commonly in
> +.B %p
> +for printing
> +.I void *
> +values.

%p works with any object pointer type (or in POSIX, any pointer type), not just 
  void *.

Should also mention "void const *", "void volatile *", etc. Plus it really 
should talk about plain "void", saying that it's a placeholder as a return value 
for functions, for casting away values, and as a keyword in C11 for functions 
with no parameters (though this is being changed in the next C version!). I sent 
comments about most of this stuff already.