Re: [PATCH v8 00/16] Add support for Clang LTO

From: Nathan Chancellor
Date: Sun Dec 06 2020 - 01:51:27 EST


On Fri, Dec 04, 2020 at 02:52:41PM -0800, Sami Tolvanen wrote:
> On Thu, Dec 3, 2020 at 2:32 PM Nick Desaulniers <ndesaulniers@xxxxxxxxxx> wrote:
> >
> > So I'd recommend to Sami to simply make the Kconfig also depend on
> > clang's integrated assembler (not just llvm-nm and llvm-ar).
>
> Sure, sounds good to me. What's the preferred way to test for this in Kconfig?
>
> It looks like actually trying to test if we have an LLVM assembler
> (e.g. using $(as-instr,.section
> ".linker-options","e",@llvm_linker_options)) doesn't work as Kconfig
> doesn't pass -no-integrated-as to clang here. I could do something
> simple like $(success,echo $(LLVM) $(LLVM_IAS) | grep -q "1 1").
>
> Thoughts?
>
> Sami

I think

depends on $(success,test $(LLVM_IAS) -eq 1)

should work, at least according to my brief test.

Cheers,
Nathan