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From: Florian Weimer <fw@deneb.enyo.de>
To: Kaylee Blake <klkblake@gmail.com>
Cc: binutils@sourceware.org
Subject: Re: RFC: [PATCH] ELF: Don't require section header on ELF objects
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Date: Mon, 09 Mar 2020 14:29:25 +0100
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* Kaylee Blake:

>> I think that's conceptually the wrong thing to do for ELF, sorry.  If
>> there is no section header, the object should be unlinkable.  The
>> linker should not use the dynamic segment to locate the symbol
>> information, only the dynamic section (in case the link ABI and
>> run-time ABI are different).
>
> I'm confused by your comment about link and run-time ABIs differing;
> surely if the ABI at runtime differs from the ABI at link time, you are
> just going to crash at runtime?

No, the typical application are fewer symbols in the DSO at link time
than at load time, for example for linking against an older version of
glibc than is installed on the system.