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In-Reply-To: <87wnsek7ku.fsf@oldenburg.str.redhat.com>
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Tue, 4 May 2021 05:30:03 -0700
Message-ID: <CAMe9rOrryDZKxyr05EYjUgn4-wu_Ndu8wZZZVMGow4PU9+_TOA@mail.gmail.com>
Subject: Re: [RFC] elf: Implement filtering of symbols historically defined in
 libpthread
To: Florian Weimer <fweimer@redhat.com>
Cc: GNU C Library <libc-alpha@sourceware.org>,
 Andreas Schwab <schwab@linux-m68k.org>
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On Tue, May 4, 2021 at 5:27 AM Florian Weimer <fweimer@redhat.com> wrote:
>
> * H. J. Lu:
>
> >> The patch attempts to detect old main programs by looking for the
> >> GLIBC_2.34 symbol version.  Since we added __libc_start_main@@GLIBC_2.34
> >> (which is called from our version of _start), all standard main programs
> >> linked with glibc 2.34 or later will have this symbol version.
>
> > Can we invent a symbol or version to detect the older binaries?
> > If not, can GNU property, ABI note, .... help here?
>
> I think we have all we need due to __libc_start_main@@GLIBC_2.34.  It
> was an unrelated change, but it helps here as well.

So your patch isn't required?  Can you add some tests to verify it?

-- 
H.J.