Re: [pocl-devel] Debug symbols for kernel

[Timo B. <tim...@gm...>]

Hi,

I did not know Oclgrind I have managed to compile it now. But oclgrind
segfaults with the kernel as well
without giving any kind of debug message (interactive stepping is not
possible either, it just segfaults). I checked the private
memory size, which is more than fine. I also tried valgrind. But the only
thing I see is that it crashes in the
kernel launcher, but not where.

I am a bit at a loss right now. Does anybody have any other ideas? It would
be good to be able to run the kernel
with full debug symbols so that valgrind or gdb can give some more useful
output. Also, it is very strange that
the Intel CPU, Nvidia GPU and AMD Gpu Opencl drivers do not pick up on an
error. Only the LLVM based implementations
in POCL and Oclgrind crash.

Best wishes

Timo



On Wed, 30 May 2018 at 15:16, Andreas Kloeckner <li...@in...>
wrote:

> Timo Betcke <tim...@gm...> writes:
> > I am observing a crash with one of my OpenCL kernels on POCL in double
> > precison (single precision works fine). I don't observe this crash on
> other
> > OpenCL implementations and printf debugging does not really show what is
> > going on.
> >
> > I am running my kernels through PyOpenCL. I tried to debug with gdb
> --args
> > python test_p1.py.
> > But while POCL debug symbols are shown, they are not shown for the
> kernel.
> > The only message I get is that the crash is in
> > _pocl_launcher_evaluate_regular. The full gdb output is shown below up to
> > the first function that has debug symbols available.
> >
> > Any hint would be great.
>
> Did you try oclgrind on that kernel? (Just a thought)
>
> Andreas
>


-- 
Dr Timo Betcke
Reader in Mathematics
University College London
Department of Mathematics
E-Mail: t.b...@uc...
Tel.: +44 (0) 20-3108-4068
Fax.: +44 (0) 20-7383-5519