Re: ABI diff tools

[Patrice Dumas <pertusus free fr>]

On Fri, Mar 23, 2007 at 12:51:03AM +0100, Axel Thimm wrote:
> On Fri, Mar 23, 2007 at 12:30:00AM +0100, Patrice Dumas wrote:
> > I am searching for a program that would allow to compare 2 libs or a lib
> > and an application, find the binary interface differences and display
> > them conveniently. Does something like that exist? I think that it would 
> > be very convenient to help maintaining ABI compatibility in EPEL packages.
> 
> That would be a nice tool, but how would it help EPEL? It would rather

I maintain library foo in epel. Upstream issue a new version. I use
the ABI comparison to patch the new version to re-add the symbols 
needed to keep ABI compatibility. But maybe this is never that 
simple...

> For creating such a tool the nearest you could get would be to simply
> dump and sort the symbols including function signatures if available
> and compare them. 

Indeed i am searching something that does that.

> But C does not encode arguments to functions into
> the symbols so large part of the ABI information is implicit. But at
> least you would get part of the ABI to check.

So that part of the ABI is only visible in header files, or by seeing
a segfault at runtime?

--
Pat