Re: [PATCH 1/4] Remove the error handling wrapper from exp and exp2

[Joseph Myers <joseph at codesourcery dot com>]

On Mon, 29 Oct 2018, Gabriel F. T. Gomes wrote:

> On Mon, 29 Oct 2018, Szabolcs Nagy wrote:
> >
> >yeah i can't find this in bugzilla, but it is a bug as far
> >as i can tell: for a symbol version only the location
> >matters where it points to, not what expression you used
> >for the location, and there is no reason to disallow
> >multiple symbol versions to point to the same location.
> 
> I also don't understand why it should be forbidden.  Do you have plans to
> report it?  You could then mention the bug number in your patch, and we
> could clean it up (comment and aliases) when glibc requires a new enough
> version of binutils.

There are lots of existing places that create aliases in order to set 
symbol versions; a comment on just one of those places wouldn't be 
particularly helpful.  If cleaning this up, I think you'd need to somehow 
locate existing places that create aliases just for setting symbol 
versions (probably by examining uses of the symbol versioning macros), 
replace the alias creation in each place with use of a common macro that 
deals with creating an alias automatically along with setting the symbol 
version (e.g. redefine versioned_symbol to create an alias using 
__COUNTER__ to define its name before doing the versioning), and then once 
all the aliases are created in a single central place, that would be the 
place to put such a comment (and to simplify once aliases aren't required 
by any binutils version supported for building glibc).

(You could do that incrementally if the new alias-creating macros have 
different names from the existing versioned_symbol etc. ones, so uses of 
the existing ones remain needing review, but on the whole I think the 
existing macros have the right names, just ought not to need manual alias 
creation.)

-- 
Joseph S. Myers
joseph@codesourcery.com