Re: [PATCH 6/7] md/raid10, LLVM: get rid of variable length array

[Dmitry Vyukov]

On Fri, Mar 17, 2017 at 8:29 PM, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> On Fri, Mar 17, 2017 at 08:26:42PM +0100, Peter Zijlstra wrote:
>> On Fri, Mar 17, 2017 at 08:05:16PM +0100, Dmitry Vyukov wrote:
>> > You can also find some reasons in the Why section of LLVM-Linux project:
>> > http://llvm.linuxfoundation.org/index.php/Main_Page
>>
>> From that:
>>
>>  - LLVM/Clang is a fast moving project with many things fixed quickly
>>    and features added.
>>
>> So what's the deal with that 5 year old bug you want us to work around?
>>
>> Also, clang doesn't support asm cc flags output and a few other
>> extensions last time I checked.
>>
>
> Another great one:
>
>  - BSD License (some people prefer this license to the GPL)
>
> Seems a very weak argument to make when talking about the Linux Kernel
> which is very explicitly GPLv2 (and not later).

OK, I guess should not have referenced the llvm-linux page.
So here are reasons on our side that I am ready to vouch:

 - clang make it possible to implement KMSAN (dynamic detection of
uses of uninit memory)
 - better code coverage for fuzzing
 - why simpler and faster development (e.g. we can port our user-space
hardening technologies -- CFI and SafeStack)

Michael is on a different team and has own reasons to do this.