RFC: Make clang the default compiler on ARM

[George Neville-Neil]

On Mar 18, 2013, at 11:33 , Warner Losh <imp at bsdimp.com> wrote:

> 
> On Mar 18, 2013, at 3:07 AM, Andrew Turner wrote:
> 
>> I would like to make clang the default compiler on ARM using the patch
>> at [1]. This only affects little-endian ARM as there is no support for
>> big-endian ARM in clang.
>> 
>> This will help me with my work to update the FreeBSD ARM ABI as I am
>> planning on moving to a hard-float ABI on armv6 as all SoCs we
>> are likely to support have at least a VFPv3-D16 floating point
>> coprocessor. The version of gcc we have in our tree does not support
>> the hard float ABI with VFP and support was added after gcc moved to
>> the GPLv3 so we are usable to make use of it.
>> 
>> The only issue I know about is an incompatibility between gcc and clang
>> with ARM EABI however this has been fixed upstream and I plan on
>> bringing it into our tree before making clang the default. If anyone
>> knows of any other issues please let me know now so I can look into
>> them.
>> 
>> If nobody brings up any issues or has any objections to me doing this
>> I will make clang the default earlier than 25 March (UTC+0).
>> 
>> Andrew
>> 
>> [1] http://people.freebsd.org/~andrew/clang/arm_clang_default.diff
> 
> This scares me, but we're at a great time in our schedule for it.
> 

I think we ought to do this, in particular since LLVM is the future of compiler tech.

Sooner we break it the sooner we can fix it :-)

Best,
George