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From:   Sami Tolvanen <samitolvanen@google.com>
Date:   Tue, 16 May 2023 07:51:29 -0700
Message-ID: <CABCJKueexnq=hE2L3uFQt5WeS2_mFckK9NHagFfU-peTnwMNeA@mail.gmail.com>
Subject: Re: [PATCH v5 21/21] kbuild: implement CONFIG_TRIM_UNUSED_KSYMS
 without recursion
To:     Masahiro Yamada <masahiroy@kernel.org>
Cc:     Nicolas Pitre <nico@fluxnic.net>, linux-kbuild@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Nicolas Schier <nicolas@fjasle.eu>
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On Mon, May 15, 2023 at 7:16=E2=80=AFPM Masahiro Yamada <masahiroy@kernel.o=
rg> wrote:
>
> On Tue, May 16, 2023 at 7:54=E2=80=AFAM Sami Tolvanen <samitolvanen@googl=
e.com> wrote:
> > A while ago there
> > was a suggestion of adding an option to LLD that allows one to pass a
> > list of symbols to preserve in relocatable LTO links, which would
> > allow us to better optimize vmlinux.o. However, I haven't had a chance
> > to look into this deeper than this proof of concept:
> >
> > https://reviews.llvm.org/D142163
>
>
> Interesting.
>
> But, scripts/generate_initcall_order.pl is still needed, right?
>
> --lto-export-symbol-list is a list of symbols,
> but it does not specify the correct order?

Correct, the patch doesn't take the order of the list into account.

Sami