diff --git a/interfaces/python/src/problem/problems.py.cpp b/interfaces/python/src/problem/problems.py.cpp
index adb5cb67ca..1e41afe5bf 100644
--- a/interfaces/python/src/problem/problems.py.cpp
+++ b/interfaces/python/src/problem/problems.py.cpp
@@ -33,7 +33,7 @@ void functional_setter_ret(FuncProb &p, std::optional<py::object> o) {
             throw std::runtime_error("FunctionalProblem function is None");
         };
     }
-};
+}
 
 template <class FuncProb, auto py_f, auto f, class Out, class Ret, class... Args>
 void functional_setter_out(FuncProb &p, std::optional<py::object> o) {
@@ -46,7 +46,7 @@ void functional_setter_out(FuncProb &p, std::optional<py::object> o) {
             throw std::runtime_error("FunctionalProblem function is None");
         };
     }
-};
+}
 
 template <class T, class... Args>
 void problem_constr_proj_methods(py::class_<T, Args...> &cls) {
diff --git a/interfaces/python/src/util/async.hpp b/interfaces/python/src/util/async.hpp
index 6ee745fb87..f19e4af736 100644
--- a/interfaces/python/src/util/async.hpp
+++ b/interfaces/python/src/util/async.hpp
@@ -21,7 +21,7 @@ auto async_solve(bool async, bool suppress_interrupt, Solver &solver, Invoker &i
         StreamReplacer stream{&solver};
         // Invoke the solver synchronously
         auto &&stats = invoke_solver();
-        return stats;
+        return static_cast<decltype(stats) &&>(stats);
     } else {
         // Check that the user doesn't use the same solver/problem in multiple threads
         ThreadChecker solver_checker{&solver};
diff --git a/src/alpaqa/include/alpaqa/util/tag-invoke.hpp b/src/alpaqa/include/alpaqa/util/tag-invoke.hpp
index 8cd2b788f1..5d4950ee68 100644
--- a/src/alpaqa/include/alpaqa/util/tag-invoke.hpp
+++ b/src/alpaqa/include/alpaqa/util/tag-invoke.hpp
@@ -14,7 +14,11 @@ namespace tag_invoke_fn_ns {
 /// Poison pill to hide overloads of foo() that might be found in parent
 /// namespace.
 /// We want to limit to only finding overloads by ADL.
+#if defined(__GNUC__) && __GNUC__ < 12 && !defined(__clang__)
+void alpaqa_tag_invoke() /* = delete */;
+#else
 void alpaqa_tag_invoke() = delete;
+#endif
 
 struct tag_invoke_fn {
     template <typename Tag, typename... Args>
diff --git a/src/alpaqa/src/driver/cancel.hpp b/src/alpaqa/src/driver/cancel.hpp
index f30bc91197..a5819e0083 100644
--- a/src/alpaqa/src/driver/cancel.hpp
+++ b/src/alpaqa/src/driver/cancel.hpp
@@ -9,7 +9,7 @@ namespace alpaqa {
 
 namespace detail {
 inline std::atomic<void *> solver_to_stop;
-};
+}
 
 /**
  * Attach SIGINT and SIGTERM handlers to stop the given solver.