Re: Should we support (not use, support) symbol versioning?

[Rich Felker <dalias@libc.org>]

On Sat, May 09, 2015 at 09:03:59PM -0400, Rich Felker wrote:
> What we could possibly do, however, is honor the version requested
> whenever the library being searched has version information. This
> would allow third-party libraries that want to use versioning to do so
> while also allowing unversioned libraries to satisfy any program or
> library using them (and work correctly as long as it's using the
> latest version API, just like now). However I'm mildly concerned that
> symbol version tables could get introduced into libraries that don't
> want them (including into libc.so) which would then horribly break
> things, e.g. if any of libgcc.a's symbols were versioned (in principle
> this should not happen, because they're all supposed to be hidden, but
> I'm not really happy relying on that).

This risk is eliminated just by adding ldso.versym=0; after
decode_dyn(&ldso) in the dynamic linker code, to ensure that any
version tables that happen to creep into libc.so/ldso are ignored.

Rich