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From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Thu, 28 Oct 2021 06:39:46 -0700
Message-ID: <CAMe9rOpwy0FcxD+VontL3TPbhShT2GAm4i9zWfzi3XEW5FaeAg@mail.gmail.com>
Subject: Re: [llvm-dev] [PATCH] Add GNU_PROPERTY_1_GLIBC_2_NEEDED
To: Florian Weimer <fweimer@redhat.com>
Cc: "H.J. Lu via llvm-dev" <llvm-dev@lists.llvm.org>,
 GNU C Library <libc-alpha@sourceware.org>, 
 Binutils <binutils@sourceware.org>, GCC Development <gcc@gcc.gnu.org>, 
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On Wed, Oct 27, 2021 at 11:52 PM Florian Weimer <fweimer@redhat.com> wrote:
>
> * H. J. Lu via llvm-dev:
>
> > 1. Some binaries which require new ELF features, like DT_RELR, only
> > work with the new glibc binary.  They crash at run-time with the older
> > glibc binaries.
> > 2. Somes binaries compiled with the new language features, like C2X
> > printf specifiers, only generate correct results with the new glibc
> > binary.  Since we don't add new glibc versions to the printf function
> > family, they generate incorrect results at run-time with the older
> > glibc binaries.
>
> Solaris uses SHT_SUNW_verneed sections for this, not a property note.
> Property notes seem the wrong approach for this.  And there is no reason
> to make this specific to glibc.
>
> However, I still very much dislike this proposal.
>

Can you share your concerns?

Thanks.

-- 
H.J.