Fix duplicate symbols

dune/solvers/iterationsteps/blockgssteps.hh

@@ -200,6 +200,7 @@ auto diagRegularize(double p, LocalSolver&& localSolver) {
 
 //! \brief is @LinearSolvers::direct with ignore nodes.
 //! \param r Regularization parameter. Set to 0.0 to switch off regularization.
+template <typename dummy = void>
 auto direct(double r = LocalSolverRegularizer::defaultDiagRegularizeParameter) {
   return [r](const auto& m, const auto& b, const auto& ignore) {
     auto directSolver = LinearSolvers::direct<std::decay_t<decltype(m)>,
@@ -213,6 +214,7 @@ auto direct(double r = LocalSolverRegularizer::defaultDiagRegularizeParameter) {
 }
 
 //! \brief is @LinearSolvers::ldlt with ignore nodes.
+template <typename dummy = void>
 auto ldlt(double r = LocalSolverRegularizer::defaultDiagRegularizeParameter) {
   return [r](const auto& m, const auto& b, const auto& ignore) {
     auto ldltSolver = LinearSolvers::ldlt<std::decay_t<decltype(m)>,
@@ -226,6 +228,7 @@ auto ldlt(double r = LocalSolverRegularizer::defaultDiagRegularizeParameter) {
 }
 
 //! \brief is @LinearSolvers::cg with ignore nodes.
+template <typename dummy = void>
 auto cg(size_t maxIter = LinearSolvers::defaultCgMaxIter,
         double tol = LinearSolvers::defaultCgTol,
         double r = LocalSolverRegularizer::defaultDiagRegularizeParameter) {

[graeser]

Maybe putting those functions in an anonymous namespace would also work. Then the symbols are not exported and each unit will have its own version.

[pipping]

It might. But these functions need to be available to the user...