ffc team mailing list archive

[Kristian Ølgaard <k.b.oelgaard@xxxxxxxxx>]

On 14 October 2011 10:51, Anders Logg <logg@xxxxxxxxx> wrote:
> The FFC tests are failing on my laptop. I might have screwed something
> up locally but it might also be related to updating to Ubuntu 11.10
> last night which has GCC 4.6.1-9ubuntu3.
>
> Here's the error I get:
>
> Verifying element 2 of 143: <CG2 on a <interval cell in R1>>
> GCC compilation failed.
>
>
> element: <CG2 on a <interval cell in R1>>,
> In file included from evaluate_basis.cpp:4:0:
> test.h: In member function 'virtual void
> test_finite_element_0::evaluate_basis(unsigned int, double*, const
> double*, const ufc::cell&) const':
> test.h:128:14: error: variable 'tmp0' set but not used
> [-Werror=unused-but-set-variable]
> test.h:165:14: error: variable 'tmp0' set but not used
> [-Werror=unused-but-set-variable]
> test.h:202:14: error: variable 'tmp0' set but not used
> [-Werror=unused-but-set-variable]
>
> Anyone else seeing this?

Yes, I also get this with the same version of GCC. The problem is code like:

      double tmp0 = 0.0;
      double tmp1 = 0.0;
      double tmp2 = 0.0;
      for (unsigned int r = 2; r < 5; r++)
      {
        tmp0 = 2.0*r*r*(2.0*r-2.0);
        tmp1 = 2.0*r*(2.0*r-1.0)*(2.0*r-2.0)/(2.0*r*r*(2.0*r-2.0));
        tmp2 = 4.0*r*(r-1.0)*(r-1.0)/(2.0*r*r*(2.0*r-2.0));
        basisvalues[r] = (X*basisvalues[r - 1]*tmp1 - basisvalues[r - 2]*tmp2);
      }// end loop over 'r'

As you see, tmp0 is not used to compute the entry in basisvalues[].
However, a value is being assigned to it in

tmp0 = 2.0*r*r*(2.0*r-2.0);

maybe this is why it is not being removed by the remove_unused()
function in cpp.py?

Kristian

> --
> Anders
>
> _______________________________________________
> Mailing list: https://launchpad.net/~ffc
> Post to     : ffc@xxxxxxxxxxxxxxxxxxx
> Unsubscribe : https://launchpad.net/~ffc
> More help   : https://help.launchpad.net/ListHelp
>