[PATCH] arm64: support __int128 with clang

[Mark Rutland]

On Tue, Apr 24, 2018 at 02:56:09PM +0100, Mark Rutland wrote:
> I belevie that currently it is not possible to use a released version of
> clang to build a working kernel without additional patches (at least
> 5.0.0, there don't seem to be any 6.0.0 binaries that can target
> AArch64). Issues include:
> 
> * Released versions of clang don't support the 's' constraint used in
>   some hyp code.
> 

> * Released versions of clang don't support 'rX' as a register name, as
>   is used by some workaround code shared between arm/arm64.

This case will apparently be fixed for 6.0.1 (and presumably 7.0.0):

https://reviews.llvm.org/rL328829
https://bugs.llvm.org/show_bug.cgi?id=36862

Neither have been released yet.

Mark.