Re: [RFC PATCH 0/3] implement dlmopen hooks for gdb

[Florian Weimer via Libc-alpha <libc-alpha@sourceware.org>]

* Carlos O'Donell:

> On 9/22/20 1:06 PM, Florian Weimer wrote:
>> * Carlos O'Donell via Libc-alpha:
>> 
>>> Your next step would be to export the symbol via Versions at the current
>>> symbol node GLIBC_2.32 (soon to be GLIBC_2.33).
>> 
>> Can we create a new GLIBC_DEBUG symbol versions for symbols which are
>> not intended to be used for run-time linking?
>> 
>> The idea is that consumers will have deal with the absence of these
>> symbols anyway, so we just need one symbol version that does not depend
>> on the glibc version for this.  Dependency management considerations
>> (that apply to symbols with run-time linking) do not come into play here.
>
> I don't object to GLIBC_DEBUG, like GLIBC_PRIVATE it can be considered
> a transient ABI that is valid only for a major release?

No, unlike GLIBC_PRIVATE, you can assume that if a GLIBC_DEBUG symbol is
there (and perhaps has the documented size), it has the documented
semantics.  But you can't assume that it is present.

The semantics of GLIBC_PRIVATE symbols can change arbitrarily, even
between builds.

Thanks,
Florian
-- 
Red Hat GmbH, https://de.redhat.com/ , Registered seat: Grasbrunn,
Commercial register: Amtsgericht Muenchen, HRB 153243,
Managing Directors: Charles Cachera, Brian Klemm, Laurie Krebs, Michael O'Neill