[RFA/solib-svr4] use AT_BASE auxiliary entry to compute load base address

[Ulrich Weigand]

Daniel Jacobowitz wrote:
> On Thu, Apr 17, 2008 at 05:11:38PM +0200, Ulrich Weigand wrote:
> > GDB used to work correctly in the presence of prelinking anyway,
> > because for regular shared libraries it detected that mismatch by
> > comparing the load addresses from the BFD it reads with those 
> > recorded in the dynamic loader's data structures (LM_ADDR_CHECK),
> > and adjusting its expectations if it detects prelinking.
> 
> Can we read the dynamic linker's ELF header from the target, to
> compare?
> 
> Wait, no, we can't... if we knew where it was loaded we wouldn't
> need AT_BASE.  Well, we could ask gdbserver to read from the
> target filesystem for us...

Yes, that's on my to-do list anyway ...

However, even that would not fix the same issue with core files
(if prelink changed a library between core file generation and 
use in GDB).

Bye,
Ulrich

-- 
  Dr. Ulrich Weigand
  GNU Toolchain for Linux on System z and Cell BE
  Ulrich.Weigand@de.ibm.com