diff --git a/libsolidity/interface/AssemblyStack.cpp b/libsolidity/interface/AssemblyStack.cpp
index 6d30f5f73..a09de3c38 100644
--- a/libsolidity/interface/AssemblyStack.cpp
+++ b/libsolidity/interface/AssemblyStack.cpp
@@ -134,7 +134,7 @@ void AssemblyStack::optimize(yul::Object& _object)
 	for (auto& subNode: _object.subObjects)
 		if (auto subObject = dynamic_cast<yul::Object*>(subNode.get()))
 			optimize(*subObject);
-	yul::OptimiserSuite::run(*languageToDialect(m_language), *_object.code, *_object.analysisInfo);
+	yul::OptimiserSuite::run(languageToDialect(m_language), *_object.code, *_object.analysisInfo);
 }
 
 MachineAssemblyObject AssemblyStack::assemble(Machine _machine, bool _optimize) const
diff --git a/libyul/optimiser/Suite.cpp b/libyul/optimiser/Suite.cpp
index aa1d4a139..3fb5a212c 100644
--- a/libyul/optimiser/Suite.cpp
+++ b/libyul/optimiser/Suite.cpp
@@ -50,7 +50,7 @@ using namespace dev;
 using namespace yul;
 
 void OptimiserSuite::run(
-	Dialect const& _dialect,
+	shared_ptr<Dialect> const& _dialect,
 	Block& _ast,
 	AsmAnalysisInfo const& _analysisInfo,
 	set<YulString> const& _externallyUsedIdentifiers
@@ -58,52 +58,52 @@ void OptimiserSuite::run(
 {
 	set<YulString> reservedIdentifiers = _externallyUsedIdentifiers;
 
-	Block ast = boost::get<Block>(Disambiguator(_dialect, _analysisInfo, reservedIdentifiers)(_ast));
+	Block ast = boost::get<Block>(Disambiguator(*_dialect, _analysisInfo, reservedIdentifiers)(_ast));
 
 	(VarDeclInitializer{})(ast);
 	(FunctionHoister{})(ast);
 	(BlockFlattener{})(ast);
 	(FunctionGrouper{})(ast);
 	EquivalentFunctionCombiner::run(ast);
-	UnusedPruner::runUntilStabilised(_dialect, ast, reservedIdentifiers);
+	UnusedPruner::runUntilStabilised(*_dialect, ast, reservedIdentifiers);
 	(ForLoopInitRewriter{})(ast);
 	(BlockFlattener{})(ast);
-	StructuralSimplifier{_dialect}(ast);
+	StructuralSimplifier{*_dialect}(ast);
 
-	NameDispenser dispenser{_dialect, ast};
+	NameDispenser dispenser{*_dialect, ast};
 
 	for (size_t i = 0; i < 4; i++)
 	{
-		ExpressionSplitter{_dialect, dispenser}(ast);
+		ExpressionSplitter{*_dialect, dispenser}(ast);
 		SSATransform::run(ast, dispenser);
-		RedundantAssignEliminator::run(_dialect, ast);
-		RedundantAssignEliminator::run(_dialect, ast);
+		RedundantAssignEliminator::run(*_dialect, ast);
+		RedundantAssignEliminator::run(*_dialect, ast);
 
-		ExpressionSimplifier::run(_dialect, ast);
-		CommonSubexpressionEliminator{_dialect}(ast);
-		StructuralSimplifier{_dialect}(ast);
+		ExpressionSimplifier::run(*_dialect, ast);
+		CommonSubexpressionEliminator{*_dialect}(ast);
+		StructuralSimplifier{*_dialect}(ast);
 		(BlockFlattener{})(ast);
 		SSATransform::run(ast, dispenser);
-		RedundantAssignEliminator::run(_dialect, ast);
-		RedundantAssignEliminator::run(_dialect, ast);
-		UnusedPruner::runUntilStabilised(_dialect, ast, reservedIdentifiers);
-		CommonSubexpressionEliminator{_dialect}(ast);
-		UnusedPruner::runUntilStabilised(_dialect, ast, reservedIdentifiers);
+		RedundantAssignEliminator::run(*_dialect, ast);
+		RedundantAssignEliminator::run(*_dialect, ast);
+		UnusedPruner::runUntilStabilised(*_dialect, ast, reservedIdentifiers);
+		CommonSubexpressionEliminator{*_dialect}(ast);
+		UnusedPruner::runUntilStabilised(*_dialect, ast, reservedIdentifiers);
 
 		SSAReverser::run(ast);
-		CommonSubexpressionEliminator{_dialect}(ast);
-		UnusedPruner::runUntilStabilised(_dialect, ast, reservedIdentifiers);
+		CommonSubexpressionEliminator{*_dialect}(ast);
+		UnusedPruner::runUntilStabilised(*_dialect, ast, reservedIdentifiers);
 
 		ExpressionJoiner::run(ast);
 		ExpressionJoiner::run(ast);
-		ExpressionInliner(_dialect, ast).run();
-		UnusedPruner::runUntilStabilised(_dialect, ast, reservedIdentifiers);
+		ExpressionInliner(*_dialect, ast).run();
+		UnusedPruner::runUntilStabilised(*_dialect, ast, reservedIdentifiers);
 
-		ExpressionSplitter{_dialect, dispenser}(ast);
+		ExpressionSplitter{*_dialect, dispenser}(ast);
 		SSATransform::run(ast, dispenser);
-		RedundantAssignEliminator::run(_dialect, ast);
-		RedundantAssignEliminator::run(_dialect, ast);
-		CommonSubexpressionEliminator{_dialect}(ast);
+		RedundantAssignEliminator::run(*_dialect, ast);
+		RedundantAssignEliminator::run(*_dialect, ast);
+		CommonSubexpressionEliminator{*_dialect}(ast);
 
 		(FunctionGrouper{})(ast);
 		EquivalentFunctionCombiner::run(ast);
@@ -111,33 +111,33 @@ void OptimiserSuite::run(
 		(BlockFlattener{})(ast);
 
 		SSATransform::run(ast, dispenser);
-		RedundantAssignEliminator::run(_dialect, ast);
-		RedundantAssignEliminator::run(_dialect, ast);
-		ExpressionSimplifier::run(_dialect, ast);
-		StructuralSimplifier{_dialect}(ast);
+		RedundantAssignEliminator::run(*_dialect, ast);
+		RedundantAssignEliminator::run(*_dialect, ast);
+		ExpressionSimplifier::run(*_dialect, ast);
+		StructuralSimplifier{*_dialect}(ast);
 		(BlockFlattener{})(ast);
-		CommonSubexpressionEliminator{_dialect}(ast);
+		CommonSubexpressionEliminator{*_dialect}(ast);
 		SSATransform::run(ast, dispenser);
-		RedundantAssignEliminator::run(_dialect, ast);
-		RedundantAssignEliminator::run(_dialect, ast);
-		UnusedPruner::runUntilStabilised(_dialect, ast, reservedIdentifiers);
-		CommonSubexpressionEliminator{_dialect}(ast);
+		RedundantAssignEliminator::run(*_dialect, ast);
+		RedundantAssignEliminator::run(*_dialect, ast);
+		UnusedPruner::runUntilStabilised(*_dialect, ast, reservedIdentifiers);
+		CommonSubexpressionEliminator{*_dialect}(ast);
 	}
 	ExpressionJoiner::run(ast);
-	Rematerialiser::run(_dialect, ast);
-	UnusedPruner::runUntilStabilised(_dialect, ast, reservedIdentifiers);
+	Rematerialiser::run(*_dialect, ast);
+	UnusedPruner::runUntilStabilised(*_dialect, ast, reservedIdentifiers);
 	ExpressionJoiner::run(ast);
-	UnusedPruner::runUntilStabilised(_dialect, ast, reservedIdentifiers);
+	UnusedPruner::runUntilStabilised(*_dialect, ast, reservedIdentifiers);
 	ExpressionJoiner::run(ast);
-	UnusedPruner::runUntilStabilised(_dialect, ast, reservedIdentifiers);
+	UnusedPruner::runUntilStabilised(*_dialect, ast, reservedIdentifiers);
 
 	SSAReverser::run(ast);
-	CommonSubexpressionEliminator{_dialect}(ast);
-	UnusedPruner::runUntilStabilised(_dialect, ast, reservedIdentifiers);
+	CommonSubexpressionEliminator{*_dialect}(ast);
+	UnusedPruner::runUntilStabilised(*_dialect, ast, reservedIdentifiers);
 
 	ExpressionJoiner::run(ast);
-	Rematerialiser::run(_dialect, ast);
-	UnusedPruner::runUntilStabilised(_dialect, ast, reservedIdentifiers);
+	Rematerialiser::run(*_dialect, ast);
+	UnusedPruner::runUntilStabilised(*_dialect, ast, reservedIdentifiers);
 
 	_ast = std::move(ast);
 }
diff --git a/libyul/optimiser/Suite.h b/libyul/optimiser/Suite.h
index 376e9889b..8aeef7608 100644
--- a/libyul/optimiser/Suite.h
+++ b/libyul/optimiser/Suite.h
@@ -38,7 +38,7 @@ class OptimiserSuite
 {
 public:
 	static void run(
-		Dialect const& _dialect,
+		std::shared_ptr<Dialect> const& _dialect,
 		Block& _ast,
 		AsmAnalysisInfo const& _analysisInfo,
 		std::set<YulString> const& _externallyUsedIdentifiers = {}
diff --git a/test/libyul/YulOptimizerTest.cpp b/test/libyul/YulOptimizerTest.cpp
index 306721a02..7b0cb1004 100644
--- a/test/libyul/YulOptimizerTest.cpp
+++ b/test/libyul/YulOptimizerTest.cpp
@@ -242,7 +242,7 @@ bool YulOptimizerTest::run(ostream& _stream, string const& _linePrefix, bool con
 		UnusedPruner::runUntilStabilised(*m_dialect, *m_ast);
 	}
 	else if (m_optimizerStep == "fullSuite")
-		OptimiserSuite::run(*m_dialect, *m_ast, *m_analysisInfo);
+		OptimiserSuite::run(m_dialect, *m_ast, *m_analysisInfo);
 	else
 	{
 		FormattedScope(_stream, _formatted, {formatting::BOLD, formatting::RED}) << _linePrefix << "Invalid optimizer step: " << m_optimizerStep << endl;