Re: [PATCH v2 3/4] Makefile: lld: tell clang to use lld

[Nick Desaulniers]

On Wed, Feb 13, 2019 at 6:59 AM Masahiro Yamada
<yamada.masahiro@xxxxxxxxxxxxx> wrote:
>
> On Tue, Feb 12, 2019 at 5:42 AM <ndesaulniers@xxxxxxxxxx> wrote:
> >
> > This is needed because clang doesn't select which linker to use based on
> > $LD but rather -fuse-ld=lld. This is problematic especially for
> > cc-ldoption, which checks for linker flag support via invoking the
> > compiler, rather than the linker.
>
>
> Sorry, please explain what kind of problem
> this patch solves.
>
>
>
> [1] $(LD) is used to link vmlinux, modules, etc.
>
> [2] $(CC) is used to link vdso, etc.
>     and -fuse-ld= selects which linker is invoked from $(CC)

It solves case 2.

>
>
> Is it a problem to use a different
> type of linker for [1] and [2] ?

Ideally, no, but I can think of at least one case where it might be
problematic to mix linkers like that:
You might be mixing linker flags added via ld-option from one linker
that aren't actually supported by the other linker.

-- 
Thanks,
~Nick Desaulniers