[PATCH v2] elf: Implement filtering of symbols historically defined in libpthread

[Florian Weimer]

* H. J. Lu:

> On Fri, May 7, 2021 at 9:29 AM Florian Weimer via Libc-alpha
> <libc-alpha@sourceware.org> wrote:
>>
>> Given that there is no consensus on the exact direction and Andreas does
>> not need it after the binutils fix, I'm going to drop this patch for
>> now.
>>
>> As I said, I might come back to this if we learn that users have many
>> binaries that they can't rebuild and that no longer work because weak
>> symbols are bound unexpectedly.
>>
>
> But we should hide symbols for undefined, weak, unversioned references
> from the old versioned binaries.

What's an old binary?

Say something linked against glibc has a weak unversioned dependency on
execveat (a new function in glibc 2.34).  Should running this program on
glibc 2.34 use glibc's execveat function or not?

Thanks,
Florian