[Dune] state of Debian packages for dune

[Carsten Gräser]

Hi,
Am 09.04.2012 11:23, schrieb Ansgar Burchardt:
> Hi,
> 
> "Christoph Grüninger" <christoph.grueninger at iws.uni-stuttgart.de>
> writes:
>> I just checked and both tests work for me (dune-grid r7984,
>> opensuse 12.1, x64, gcc 4.6.2). Ansgar, maybe you can print
>> out the values of the assertion? Maybe it's only a problem
>> with floating point number comparison.
> 
> It works for me on amd64 as well and Debian's buildd for powerpc also
> built the package successfully.  In addition the numbers look the same:
> 
>   geomCopy.global(pos) != glob: 0.0083333333333333332177 != 0.0083333333333333332177
> 
> I tried rebuilding with `-fpmath=sse' and the tests pass.  So this might
> be caused by the 80bit precision the 387 FPU uses internally (as far as
> I know this causes numeric differences if a value is stored in the main
> memory and then loaded into a FPU register again).
to check if this is really the issue, you could also assign
the results to variables and compile with '-ffloat-store'
Normally the variables could be optimized away, but this flag
ensures that all floats are really stored to memory before accessing
them again.

Best,
Carsten