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  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]
Date:   Mon, 3 Apr 2017 06:46:02 +0900
From:   Masahiro Yamada <yamada.masahiro@...ionext.com>
To:     Arnd Bergmann <arnd@...db.de>
Cc:     Mark Charlebois <charlebm@...il.com>,
        Behan Webster <behanw@...verseincode.com>,
        Michal Marek <mmarek@...e.com>,
        Nicolas Pitre <nicolas.pitre@...aro.org>,
        Kees Cook <keescook@...omium.org>,
        Emese Revfy <re.emese@...il.com>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] kbuild, LLVMLinux: Add -Werror to cc-option to support clang

Hi Arnd,


2017-04-01 5:38 GMT+09:00 Arnd Bergmann <arnd@...db.de>:
> From: Mark Charlebois <charlebm@...il.com>
>
> Clang will warn about unknown warnings but will not return false
> unless -Werror is set. GCC will return false if an unknown
> warning is passed.
>
> Adding -Werror make both compiler behave the same.
>
> [arnd: it turns out we need the same patch for testing whether -ffunction-sections
>        works right with gcc. I've build tested extensively with this patch
>        applied, so let's just merge this one now.]
>
> Signed-off-by: Mark Charlebois <charlebm@...il.com>
> Signed-off-by: Behan Webster <behanw@...verseincode.com>
> Reviewed-by: Jan-Simon Möller <dl9pf@....de>
> Signed-off-by: Arnd Bergmann <arnd@...db.de>


Thank you for forwarding this patch.


The code diff looks good to me,
but I'd like to be sure about git-log before applying it.


As far as I tested, the statement
"Clang will warn about unknown warnings but will not
return false unless -Werror is set." does not seem true
on recent versions.



[1] When I use version 3.3

masahiro@...ver:~$ clang --version
clang version 3.3 (tags/RELEASE_33/final)
Target: x86_64-unknown-linux-gnu
Thread model: posix
masahiro@...ver:~$ clang  -foobar -c -x c /dev/null
clang: warning: argument unused during compilation: '-foobar'
masahiro@...ver:~$ echo $?
0


[2] When I use version 3.4

masahiro@...ver:~$ clang --version
clang version 3.4 (tags/RELEASE_34/final)
Target: x86_64-unknown-linux-gnu
Thread model: posix
masahiro@...ver:~$ clang  -foobar -c -x c /dev/null
clang: error: unknown argument: '-foobar'
masahiro@...ver:~$ echo $?
1




I agree we can apply this patch anyway
even if the original motivation is not true anymore.


Can you check it out,
and add a little more comments if you agree?


-- 
Best Regards
Masahiro Yamada

Powered by blists - more mailing lists