Re: shlib-compat.h

[Roland McGrath <roland at frob dot com>]

> Roland McGrath <roland@frob.com> writes:
> 
> > That is just not true.  There is _dl_check_map_versions, called on each
> > object loaded, that does work linear in the number of version sets.
> 
> This is completely neglectable.

I'll assume you mean "negligible".  I think that every little bit helps,
especially in the dynamic linking start-up costs.  And this is something
that grows slowly over time as more minor versions are added, and rarely
shrinks agains (since that would only happen with a soname change).

> It makes it very much harder for somebody who has no access to the
> platform using this to find out which files are involved.  Function
> names hould be unique over all platforms.  This is the only possible
> way one can identify problems and report solutions.

I find this argument pretty thin; it's already the case that you have to
guess the sysdeps selection for another platform to know you're looking at
the right source files.  The fact of the matter is that the whole
versioning scheme at all is going to be fairly confusing for anyone reading
it afresh to figure out in the source.  And once one does know the scheme,
then a quick glance at shlib-versions looking for the platform in question
unambiguously tells you how to translate the source-code version names into
the ABI versions for that platform.