[PATCH 13/15] arm64: fix mrs_s/msr_s macros for clang LTO

Nick Desaulniers ndesaulniers at google.com
Fri Nov 3 11:15:55 PDT 2017


On Fri, Nov 3, 2017 at 11:06 AM, Mark Rutland <mark.rutland at arm.com> wrote:
> On Fri, Nov 03, 2017 at 10:53:08AM -0700, Nick Desaulniers wrote:
>> These mrs_s and msr_s macros in particular were preventing us from
>> linking arm64 with Clang's integrated assembler, regardless of LTO.
>> Those macros ran into: https://bugs.llvm.org/show_bug.cgi?id=19749.
>> So while I appreciate how clever they are, they prevent us from
>> assembling with Clang so I would like to see them go.
>
> They're necessary to work with some currently-supported toolchains
> (which don't support the s*_*_c*_c*_* syntax), so they're not going to
> go completely.
>
> If you could suggest something that clang might prefer, which doesn't
> adversely affect GCC, I'm all ears.

I wasn't clear in my point; I recognize what they do and agree that
they are needed.

More specifically, my problem is the use of .macro assembly
directives, since Clang "considers it a feature" not to let you invoke
a .macro defined in one inline asm block from another asm inline
block.

So I would like to see *the use of .macro in separate inline asm
blocks within mrs_s and msr_s c-preprocessor macros go.*



More information about the linux-arm-kernel mailing list