Merge commit 'ba11e6d217fbbf9e25ec85bd7f74e5f29b98c3c5'

framework/include/base/Assembly.h

@@ -2771,11 +2771,19 @@ Assembly::processDerivatives(const std::vector<ADReal> & residuals,
     auto current_dofs_set = std::set<dof_id_type>(resid_it->derivatives().nude_indices().begin(),
                                                   resid_it->derivatives().nude_indices().end());
     mooseAssert(compare_dofs_set == current_dofs_set,
-                "We're going to see whether the dof sets are the same");
+                "We're going to see whether the dof sets are the same. IIRC the degree of freedom "
+                "dependence (as indicated by the dof index set held by the ADReal) has to be the "
+                "same for every residual passed to this method otherwise constrain_element_matrix "
+                "will not work.");
   }
 #endif
   auto column_indices = std::vector<dof_id_type>(compare_dofs.begin(), compare_dofs.end());
 
+  // If there's no derivatives then there is nothing to do. Moreover, if we pass zero size column
+  // indices to constrain_element_matrix then we will potentially get errors out of BLAS
+  if (!column_indices.size())
+    return;
+
   DenseMatrix<Number> element_matrix(row_indices.size(), column_indices.size());
   for (const auto i : index_range(row_indices))
   {

modules/ray_tracing/test/tests/userobjects/ray_tracing_study/errors/tests

@@ -222,6 +222,7 @@
                   Executioner/type=Eigenvalue'
       expect_err = 'is not supported for an eigenvalue solve.'
       allow_test_objects = true
+      slepc = true
       detail = 'when the study is set to execute with residual kernels and an eigenvalue executioner,'
     []
     [error_if_tracing]

test/tests/kernels/diffusion_with_hanging_node/ad_simple_diffusion.i

@@ -15,6 +15,11 @@
     type = ADDiffusion
     variable = u
   [../]
+  [force]
+    type = ADBodyForce
+    variable = u
+    function = '0'
+  []
 []
 
 [BCs]

test/tests/kernels/diffusion_with_hanging_node/tests

@@ -47,7 +47,7 @@
     type = PetscJacobianTester
     input = 'ad_simple_diffusion.i'
     run_sim = True
-    requirement = 'The system shall compute a perfect Jacobian via automatic differentiation for a hanging-node problem.'
+    requirement = 'The system shall compute a perfect Jacobian via automatic differentiation for a hanging-node problem and simultaneously handle automatic differentiation objects that do not actually have nonlinear variable dependence.'
     issues = 'libmesh#1985 #15732'
   []
 []

test/tests/problems/eigen_problem/initial_condition/tests

@@ -17,6 +17,7 @@
     csvdiff = 'ne_ic_no_free_out_eigenvalues_0001.csv'
     issues = '#17026'
     requirement = "The system shall support eigenvalue execution without free power iterations."
+    slepc = true
   [../]
 
   [./inverse_eigenvalue_postprocessor]