remove templates from make_sparsity_pattern

[necioglu]

Following PR of dealii dealii/dealii#14433 removes the templates from

exadg/include/exadg/operators/operator_base.cpp

Line 789 in f7c3c2f

dealii::MGTools::make_sparsity_pattern<dim, dim, dealii::DynamicSparsityPattern, Number>(

.

Made Exadg compatible with the changes. Thanks to @bergbauer

Closes #279

[peterrum]

@nfehn Do we care about keeping compatibility with release 9.4?

[kronbichler]

@nfehn Do we care about keeping compatibility with release 9.4?

Shouldn't we still be compatible? I don't see immediately why we would have needed to specify the template arguments and not rely on the automatic deduction for the 9.4 release.

[nfehn]

I think we decided to only test against dealii:master, right?

[peterrum]

I think we decided to only test against dealii:master, right?

No, we have not. We decided on dropping the testing of 9.3 a few weeks before the 9.4 release. I don't mind if we keep it like this. But there will be a time when we need to start versioning once we have more users.

[nfehn]

But everything is green, so where would such an incompatibility with dealii-9.4 show up?

Principally, we should for now decide for a solution that allows most efficient progress. dealii promises to not make incompatible changes, but in practice it happens every few weeks to months. So I don't know what's best.

[kronbichler]

dealii promises to not make incompatible changes, but in practice it happens every few weeks to months.

While I agree that we should (a) make sure to enable quick progress, but also (b) at some point have the facilities to support multiple versions of deal.II, I do not understand the issue here. Has someone tested that the current code actually is not compatible with version 9.4? In my experience, 80% of the issues we have with deal.II are things where a change we make is still compatible with the old version in deal.II (like I suppose is the case here, but I didn't test it). This helps us to make the code better overall.

[nfehn]

I just wanted to mention that this type of changes in ExaDG happen regularily. I do not criticize this. So I definitely appreciate overall progress in deal.II, but at the same time we have to find a good solution for ExaDG, and for that I think we need to take into account that such incompatible changes happen in deal.II.