objcopy copies not only symbols asked?

[Gyurki, Istvan (MED)]

> -----Original Message-----
> From: Fergus Henderson [mailto:fjh@cs.mu.oz.au]
> Sent: 2003. februar 24. 14:02
> To: Gyurki, Istvan (MED)
> Cc: gcc@gcc.gnu.org
> Subject: Re: objcopy copies not only symbols asked?
> 
> 
> On 24-Feb-2003, Gyurki, Istvan (MED) <Istvan.Gyurki@med.ge.com> wrote:
> > I have a .o file about 1 meg size. I'd like to extract only 
> one symbol from
> > it, using:
> >   objcopy --strip-all -K symbolname from.o to.o
> > 
> > objcopy does the job, however the new file containing only 
> one symbol wil be
> > about 800k.
> > I do not think that the symbol takes up that much space, so 
> for me it seems
> > that objcopy only removes symbol reference, but does not 
> actually eliminate
> > everything.
> > 
> > My question is; is there a way to create .o file containing only the
> > required symbol, and not more?
> 
> If you build with -ffunction-sections and -fdata-sections, then you
> may be able to use the linker to do this (e.g. "ld -r --gc-sections
> -u symbolname -o to.o from.o"; I haven't actually tried this).
> 
> But if the object file was not built with -ffunction-sections and
> -fdata-sections, then I think you're out of luck. 
> 

Thanks!
Unfortunately -r and --gc-sections cannot be used together.
When I try to simply link against an archive with --function-sections, I get
"relocation truncated to fit" errors... :(

Istvan