Re: [Libunwind-devel] symbol size?

[David Mosberger-Tang]

Hi Andrew,

On 2/28/07, Andrew Cagney <address@hidden> wrote:
> David Mosberger-Tang wrote:
> > Hi Andrew,
> >
> > On 2/27/07, Andrew Cagney <address@hidden> wrote:
> >> Is it possible to get the symbol's size using libunwind?
> >
> > Not really.
>
> How should this be added?  The obvious change - modify
> unw_get_proc_name's signature to return start/size would be abi breaking.

Breaking the ABI isn't acceptable, as you guessed, so we'd have to
introduce a new function.

The bigger problem to me is the question of how you define the "size".
For example, consider a function with multiple discontiguous code
sections. Asking the name for those code sections is well defined (you
should always get back the name of the underlying function), but how
would you define the "size" in such a case?  I assume you just want to
get a hold of the "size" member associated with the ELF symbol of the
function, but I don't want to make the libunwind API that ELF
specific.  Earlier you asked about how to split/implement
symbol-related code with libunwind and elfutils.  I think that's
something worth rethinking.  The stuff in libunwind is meant to be
minimal.  If we could reasonably all push it out to elfutils, I
certainly wouldn't object to that.

 --david
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