From 9324fb4f20a848609ea417299869ece0044c44f5 Mon Sep 17 00:00:00 2001
From: chriseth <chris@ethereum.org>
Date: Mon, 4 May 2020 18:38:00 +0200
Subject: [PATCH 1/5] Free functions.

---
 libsolidity/analysis/GlobalContext.cpp        | 17 +++-
 libsolidity/analysis/GlobalContext.h          |  1 +
 libsolidity/analysis/NameAndTypeResolver.cpp  | 10 ++
 libsolidity/analysis/StaticAnalyzer.cpp       |  1 +
 libsolidity/analysis/SyntaxChecker.cpp        | 30 +++++-
 libsolidity/analysis/SyntaxChecker.h          |  3 +-
 libsolidity/analysis/TypeChecker.cpp          | 95 +++++++++++++------
 libsolidity/analysis/TypeChecker.h            | 10 ++
 libsolidity/analysis/ViewPureChecker.cpp      | 36 +++----
 libsolidity/analysis/ViewPureChecker.h        |  1 +
 libsolidity/ast/AST.cpp                       | 11 ++-
 libsolidity/ast/AST.h                         |  8 ++
 libsolidity/ast/ASTAnnotations.h              |  3 -
 libsolidity/ast/ASTJsonConverter.cpp          |  2 +-
 libsolidity/ast/ASTJsonImporter.cpp           | 16 +++-
 libsolidity/ast/Types.cpp                     | 16 ++--
 libsolidity/codegen/ExpressionCompiler.cpp    | 10 +-
 libsolidity/parsing/Parser.cpp                |  8 +-
 libsolidity/parsing/Parser.h                  |  2 +-
 .../semanticTests/freeFunctions/easy.sol      | 13 +++
 .../freeFunctions/free_runtimecode.sol        | 15 +++
 .../semanticTests/freeFunctions/import.sol    | 18 ++++
 .../freeFunctions/libraries_from_free.sol     | 21 ++++
 .../freeFunctions/new_operator.sol            | 15 +++
 .../semanticTests/freeFunctions/overloads.sol | 16 ++++
 .../semanticTests/freeFunctions/recursion.sol | 23 +++++
 .../freeFunctions/storage_calldata_refs.sol   | 17 ++++
 .../free_call_via_contract_type.sol           |  8 ++
 .../freeFunctions/free_constructor.sol        |  3 +
 .../freeFunctions/free_fallback.sol           |  3 +
 .../freeFunctions/free_function_modifier.sol  |  4 +
 .../free_function_qualified_modifier.sol      |  9 ++
 .../freeFunctions/free_function_shadowing.sol |  9 ++
 .../free_function_visibility.sol              |  5 +
 .../free_function_without_body.sol            |  3 +
 .../freeFunctions/free_functions.sol          |  4 +
 .../freeFunctions/free_mutability.sol         |  8 ++
 .../freeFunctions/free_overload.sol           |  9 ++
 .../freeFunctions/free_override.sol           |  4 +
 .../freeFunctions/free_payable.sol            |  4 +
 .../freeFunctions/free_receive.sol            |  3 +
 .../freeFunctions/free_storage.sol            |  4 +
 .../freeFunctions/free_virtual.sol            |  4 +
 .../function_same_name_as_contract.sol        |  4 +
 .../function_using_struct_after_contract.sol  |  6 ++
 .../syntaxTests/freeFunctions/gas_value.sol   |  6 ++
 .../freeFunctions/qualified_struct_access.sol |  7 ++
 .../freeFunctions/struct_after_function.sol   |  3 +
 .../freeFunctions/super_in_free_function.sol  |  6 ++
 .../freeFunctions/this_in_free_function.sol   |  6 ++
 .../imports/importing_free_functions.sol      | 14 +++
 51 files changed, 481 insertions(+), 73 deletions(-)
 create mode 100644 test/libsolidity/semanticTests/freeFunctions/easy.sol
 create mode 100644 test/libsolidity/semanticTests/freeFunctions/free_runtimecode.sol
 create mode 100644 test/libsolidity/semanticTests/freeFunctions/import.sol
 create mode 100644 test/libsolidity/semanticTests/freeFunctions/libraries_from_free.sol
 create mode 100644 test/libsolidity/semanticTests/freeFunctions/new_operator.sol
 create mode 100644 test/libsolidity/semanticTests/freeFunctions/overloads.sol
 create mode 100644 test/libsolidity/semanticTests/freeFunctions/recursion.sol
 create mode 100644 test/libsolidity/semanticTests/freeFunctions/storage_calldata_refs.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/free_call_via_contract_type.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/free_constructor.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/free_fallback.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/free_function_modifier.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/free_function_qualified_modifier.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/free_function_shadowing.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/free_function_visibility.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/free_function_without_body.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/free_functions.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/free_mutability.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/free_overload.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/free_override.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/free_payable.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/free_receive.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/free_storage.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/free_virtual.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/function_same_name_as_contract.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/function_using_struct_after_contract.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/gas_value.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/qualified_struct_access.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/struct_after_function.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/super_in_free_function.sol
 create mode 100644 test/libsolidity/syntaxTests/freeFunctions/this_in_free_function.sol
 create mode 100644 test/libsolidity/syntaxTests/imports/importing_free_functions.sol

diff --git a/libsolidity/analysis/GlobalContext.cpp b/libsolidity/analysis/GlobalContext.cpp
index 885ae49a7..dee7e8220 100644
--- a/libsolidity/analysis/GlobalContext.cpp
+++ b/libsolidity/analysis/GlobalContext.cpp
@@ -134,15 +134,26 @@ vector<Declaration const*> GlobalContext::declarations() const
 MagicVariableDeclaration const* GlobalContext::currentThis() const
 {
 	if (!m_thisPointer[m_currentContract])
-		m_thisPointer[m_currentContract] = make_shared<MagicVariableDeclaration>(magicVariableToID("this"), "this", TypeProvider::contract(*m_currentContract));
+	{
+		Type const* type = TypeProvider::emptyTuple();
+		if (m_currentContract)
+			type = TypeProvider::contract(*m_currentContract);
+		m_thisPointer[m_currentContract] =
+			make_shared<MagicVariableDeclaration>(magicVariableToID("this"), "this", type);
+	}
 	return m_thisPointer[m_currentContract].get();
-
 }
 
 MagicVariableDeclaration const* GlobalContext::currentSuper() const
 {
 	if (!m_superPointer[m_currentContract])
-		m_superPointer[m_currentContract] = make_shared<MagicVariableDeclaration>(magicVariableToID("super"), "super", TypeProvider::contract(*m_currentContract, true));
+	{
+		Type const* type = TypeProvider::emptyTuple();
+		if (m_currentContract)
+			type = TypeProvider::contract(*m_currentContract, true);
+		m_superPointer[m_currentContract] =
+			make_shared<MagicVariableDeclaration>(magicVariableToID("super"), "super", type);
+	}
 	return m_superPointer[m_currentContract].get();
 }
 
diff --git a/libsolidity/analysis/GlobalContext.h b/libsolidity/analysis/GlobalContext.h
index b84e3a026..191359c60 100644
--- a/libsolidity/analysis/GlobalContext.h
+++ b/libsolidity/analysis/GlobalContext.h
@@ -46,6 +46,7 @@ class GlobalContext: private boost::noncopyable
 public:
 	GlobalContext();
 	void setCurrentContract(ContractDefinition const& _contract);
+	void resetCurrentContract() { m_currentContract = nullptr; }
 	MagicVariableDeclaration const* currentThis() const;
 	MagicVariableDeclaration const* currentSuper() const;
 
diff --git a/libsolidity/analysis/NameAndTypeResolver.cpp b/libsolidity/analysis/NameAndTypeResolver.cpp
index c7be364a3..957046810 100644
--- a/libsolidity/analysis/NameAndTypeResolver.cpp
+++ b/libsolidity/analysis/NameAndTypeResolver.cpp
@@ -275,6 +275,12 @@ bool NameAndTypeResolver::resolveNamesAndTypesInternal(ASTNode& _node, bool _res
 			if (!resolveNamesAndTypesInternal(*node, true))
 				success = false;
 		}
+
+		// make "this" and "super" invisible.
+		m_scopes[nullptr]->registerDeclaration(*m_globalContext.currentThis(), nullptr, true, true);
+		m_scopes[nullptr]->registerDeclaration(*m_globalContext.currentSuper(), nullptr, true, true);
+		m_globalContext.resetCurrentContract();
+
 		return success;
 	}
 	else
@@ -548,6 +554,10 @@ bool DeclarationRegistrationHelper::visit(ContractDefinition& _contract)
 
 void DeclarationRegistrationHelper::endVisit(ContractDefinition&)
 {
+	// make "this" and "super" invisible.
+	m_scopes[nullptr]->registerDeclaration(*m_globalContext.currentThis(), nullptr, true, true);
+	m_scopes[nullptr]->registerDeclaration(*m_globalContext.currentSuper(), nullptr, true, true);
+	m_globalContext.resetCurrentContract();
 	m_currentContract = nullptr;
 	closeCurrentScope();
 }
diff --git a/libsolidity/analysis/StaticAnalyzer.cpp b/libsolidity/analysis/StaticAnalyzer.cpp
index cd932cf6d..a6d797910 100644
--- a/libsolidity/analysis/StaticAnalyzer.cpp
+++ b/libsolidity/analysis/StaticAnalyzer.cpp
@@ -311,6 +311,7 @@ bool StaticAnalyzer::visit(FunctionCall const& _functionCall)
 						);
 		}
 		if (
+			m_currentContract &&
 			m_currentContract->isLibrary() &&
 			functionType->kind() == FunctionType::Kind::DelegateCall &&
 			functionType->declaration().scope() == m_currentContract
diff --git a/libsolidity/analysis/SyntaxChecker.cpp b/libsolidity/analysis/SyntaxChecker.cpp
index c0380ffe5..a47d522d9 100644
--- a/libsolidity/analysis/SyntaxChecker.cpp
+++ b/libsolidity/analysis/SyntaxChecker.cpp
@@ -295,7 +295,7 @@ bool SyntaxChecker::visit(PlaceholderStatement const&)
 
 bool SyntaxChecker::visit(ContractDefinition const& _contract)
 {
-	m_isInterface = _contract.isInterface();
+	m_currentContractKind = _contract.contractKind();
 
 	ASTString const& contractName = _contract.name();
 	for (FunctionDefinition const* function: _contract.definedFunctions())
@@ -309,19 +309,41 @@ bool SyntaxChecker::visit(ContractDefinition const& _contract)
 	return true;
 }
 
+void SyntaxChecker::endVisit(ContractDefinition const&)
+{
+	m_currentContractKind = std::nullopt;
+}
+
 bool SyntaxChecker::visit(FunctionDefinition const& _function)
 {
-	if (!_function.isConstructor() && _function.noVisibilitySpecified())
+	solAssert(_function.isFree() == (m_currentContractKind == std::nullopt), "");
+
+	if (!_function.isFree() && !_function.isConstructor() && _function.noVisibilitySpecified())
 	{
-		string suggestedVisibility = _function.isFallback() || _function.isReceive() || m_isInterface ? "external" : "public";
+		string suggestedVisibility =
+			_function.isFallback() ||
+			_function.isReceive() ||
+			m_currentContractKind == ContractKind::Interface
+		? "external" : "public";
 		m_errorReporter.syntaxError(
 			4937_error,
 			_function.location(),
 			"No visibility specified. Did you intend to add \"" + suggestedVisibility + "\"?"
 		);
 	}
+	else if (_function.isFree())
+	{
+		if (!_function.noVisibilitySpecified())
+			m_errorReporter.syntaxError(
+				4126_error,
+				_function.location(),
+				"Free functions cannot have visibility."
+			);
+		if (!_function.isImplemented())
+			m_errorReporter.typeError(4668_error, _function.location(), "Free functions must be implemented.");
+	}
 
-	if (m_isInterface && !_function.modifiers().empty())
+	if (m_currentContractKind == ContractKind::Interface && !_function.modifiers().empty())
 		m_errorReporter.syntaxError(5842_error, _function.location(), "Functions in interfaces cannot have modifiers.");
 	else if (!_function.isImplemented() && !_function.modifiers().empty())
 		m_errorReporter.syntaxError(2668_error, _function.location(), "Functions without implementation cannot have modifiers.");
diff --git a/libsolidity/analysis/SyntaxChecker.h b/libsolidity/analysis/SyntaxChecker.h
index 1ace2f36a..a5b786e34 100644
--- a/libsolidity/analysis/SyntaxChecker.h
+++ b/libsolidity/analysis/SyntaxChecker.h
@@ -83,6 +83,7 @@ private:
 	bool visit(PlaceholderStatement const& _placeholderStatement) override;
 
 	bool visit(ContractDefinition const& _contract) override;
+	void endVisit(ContractDefinition const& _contract) override;
 	bool visit(FunctionDefinition const& _function) override;
 	bool visit(FunctionTypeName const& _node) override;
 
@@ -102,7 +103,7 @@ private:
 	bool m_versionPragmaFound = false;
 
 	int m_inLoopDepth = 0;
-	bool m_isInterface = false;
+	std::optional<ContractKind> m_currentContractKind;
 
 	SourceUnit const* m_sourceUnit = nullptr;
 };
diff --git a/libsolidity/analysis/TypeChecker.cpp b/libsolidity/analysis/TypeChecker.cpp
index 8ebc76291..28f2b4152 100644
--- a/libsolidity/analysis/TypeChecker.cpp
+++ b/libsolidity/analysis/TypeChecker.cpp
@@ -271,6 +271,7 @@ void TypeChecker::endVisit(InheritanceSpecifier const& _inheritance)
 {
 	auto base = dynamic_cast<ContractDefinition const*>(&dereference(_inheritance.name()));
 	solAssert(base, "Base contract not available.");
+	solAssert(m_currentContract, "");
 
 	if (m_currentContract->isInterface() && !base->isInterface())
 		m_errorReporter.typeError(6536_error, _inheritance.location(), "Interfaces can only inherit from other interfaces.");
@@ -327,7 +328,9 @@ bool TypeChecker::visit(FunctionDefinition const& _function)
 {
 	if (_function.markedVirtual())
 	{
-		if (_function.isConstructor())
+		if (_function.isFree())
+			m_errorReporter.syntaxError(4493_error, _function.location(), "Free functions cannot be virtual.");
+		else if (_function.isConstructor())
 			m_errorReporter.typeError(7001_error, _function.location(), "Constructors cannot be virtual.");
 		else if (_function.annotation().contract->isInterface())
 			m_errorReporter.warning(5815_error, _function.location(), "Interface functions are implicitly \"virtual\"");
@@ -336,12 +339,16 @@ bool TypeChecker::visit(FunctionDefinition const& _function)
 		else if (_function.libraryFunction())
 			m_errorReporter.typeError(7801_error, _function.location(), "Library functions cannot be \"virtual\".");
 	}
+	if (_function.overrides() && _function.isFree())
+		m_errorReporter.syntaxError(1750_error, _function.location(), "Free functions cannot override.");
 
 	if (_function.isPayable())
 	{
 		if (_function.libraryFunction())
 			m_errorReporter.typeError(7708_error, _function.location(), "Library functions cannot be payable.");
-		if (_function.isOrdinary() && !_function.isPartOfExternalInterface())
+		else if (_function.isFree())
+			m_errorReporter.typeError(9559_error, _function.location(), "Free functions cannot be payable.");
+		else if (_function.isOrdinary() && !_function.isPartOfExternalInterface())
 			m_errorReporter.typeError(5587_error, _function.location(), "\"internal\" and \"private\" functions cannot be payable.");
 	}
 
@@ -415,9 +422,13 @@ bool TypeChecker::visit(FunctionDefinition const& _function)
 	set<Declaration const*> modifiers;
 	for (ASTPointer<ModifierInvocation> const& modifier: _function.modifiers())
 	{
-		auto baseContracts = dynamic_cast<ContractDefinition const&>(*_function.scope()).annotation().linearizedBaseContracts;
-		// Delete first base which is just the main contract itself
-		baseContracts.erase(baseContracts.begin());
+		vector<ContractDefinition const*> baseContracts;
+		if (auto contract = dynamic_cast<ContractDefinition const*>(_function.scope()))
+		{
+			baseContracts = contract->annotation().linearizedBaseContracts;
+			// Delete first base which is just the main contract itself
+			baseContracts.erase(baseContracts.begin());
+		}
 
 		visitManually(
 			*modifier,
@@ -432,7 +443,15 @@ bool TypeChecker::visit(FunctionDefinition const& _function)
 		else
 			modifiers.insert(decl);
 	}
-	if (m_currentContract->isInterface())
+
+	solAssert(_function.isFree() == !m_currentContract, "");
+	if (!m_currentContract)
+	{
+		solAssert(!_function.isConstructor(), "");
+		solAssert(!_function.isFallback(), "");
+		solAssert(!_function.isReceive(), "");
+	}
+	else if (m_currentContract->isInterface())
 	{
 		if (_function.isImplemented())
 			m_errorReporter.typeError(4726_error, _function.location(), "Functions in interfaces cannot have an implementation.");
@@ -445,6 +464,7 @@ bool TypeChecker::visit(FunctionDefinition const& _function)
 	else if (m_currentContract->contractKind() == ContractKind::Library)
 		if (_function.isConstructor())
 			m_errorReporter.typeError(7634_error, _function.location(), "Constructor cannot be defined in libraries.");
+
 	if (_function.isImplemented())
 		_function.body().accept(*this);
 	else if (_function.isConstructor())
@@ -452,7 +472,12 @@ bool TypeChecker::visit(FunctionDefinition const& _function)
 	else if (_function.libraryFunction())
 		m_errorReporter.typeError(9231_error, _function.location(), "Library functions must be implemented if declared.");
 	else if (!_function.virtualSemantics())
-		m_errorReporter.typeError(5424_error, _function.location(), "Functions without implementation must be marked virtual.");
+	{
+		if (_function.isFree())
+			solAssert(m_errorReporter.hasErrors(), "");
+		else
+			m_errorReporter.typeError(5424_error, _function.location(), "Functions without implementation must be marked virtual.");
+	}
 
 
 	if (_function.isFallback())
@@ -1726,7 +1751,9 @@ void TypeChecker::typeCheckFunctionCall(
 
 	if (_functionType->kind() == FunctionType::Kind::Declaration)
 	{
+		solAssert(_functionType->declaration().annotation().contract, "");
 		if (
+			m_currentContract &&
 			m_currentContract->derivesFrom(*_functionType->declaration().annotation().contract) &&
 			!dynamic_cast<FunctionDefinition const&>(_functionType->declaration()).isImplemented()
 		)
@@ -2454,18 +2481,23 @@ void TypeChecker::endVisit(NewExpression const& _newExpression)
 		if (contract->abstract())
 			m_errorReporter.typeError(4614_error, _newExpression.location(), "Cannot instantiate an abstract contract.");
 
-		solAssert(!!m_currentContract, "");
-		m_currentContract->annotation().contractDependencies.insert(contract);
-		solAssert(
-			!contract->annotation().linearizedBaseContracts.empty(),
-			"Linearized base contracts not yet available."
-		);
-		if (contractDependenciesAreCyclic(*m_currentContract))
-			m_errorReporter.typeError(
-				4579_error,
-				_newExpression.location(),
-				"Circular reference for contract creation (cannot create instance of derived or same contract)."
+		if (m_currentContract)
+		{
+			// TODO this is not properly detecting creation-cycles if they go through
+			// internal library functions or free functions. It will be caught at
+			// code generation time, but it would of course be better to catch it here.
+			m_currentContract->annotation().contractDependencies.insert(contract);
+			solAssert(
+				!contract->annotation().linearizedBaseContracts.empty(),
+				"Linearized base contracts not yet available."
 			);
+			if (contractDependenciesAreCyclic(*m_currentContract))
+				m_errorReporter.typeError(
+					4579_error,
+					_newExpression.location(),
+					"Circular reference for contract creation (cannot create instance of derived or same contract)."
+				);
+		}
 
 		_newExpression.annotation().type = FunctionType::newExpressionType(*contract);
 	}
@@ -2507,7 +2539,7 @@ bool TypeChecker::visit(MemberAccess const& _memberAccess)
 
 	// Retrieve the types of the arguments if this is used to call a function.
 	auto const& arguments = _memberAccess.annotation().arguments;
-	MemberList::MemberMap possibleMembers = exprType->members(m_currentContract).membersByName(memberName);
+	MemberList::MemberMap possibleMembers = exprType->members(currentDefinitionScope()).membersByName(memberName);
 	size_t const initialMemberCount = possibleMembers.size();
 	if (initialMemberCount > 1 && arguments)
 	{
@@ -2533,7 +2565,7 @@ bool TypeChecker::visit(MemberAccess const& _memberAccess)
 				DataLocation::Storage,
 				exprType
 			);
-			if (!storageType->members(m_currentContract).membersByName(memberName).empty())
+			if (!storageType->members(currentDefinitionScope()).membersByName(memberName).empty())
 				m_errorReporter.fatalTypeError(
 					4994_error,
 					_memberAccess.location(),
@@ -2691,8 +2723,6 @@ bool TypeChecker::visit(MemberAccess const& _memberAccess)
 		{
 			annotation.isPure = true;
 			ContractType const& accessedContractType = dynamic_cast<ContractType const&>(*magicType->typeArgument());
-			m_currentContract->annotation().contractDependencies.insert(&accessedContractType.contractDefinition());
-
 			if (
 				memberName == "runtimeCode" &&
 				!accessedContractType.immutableVariables().empty()
@@ -2703,12 +2733,21 @@ bool TypeChecker::visit(MemberAccess const& _memberAccess)
 					"\"runtimeCode\" is not available for contracts containing immutable variables."
 				);
 
-			if (contractDependenciesAreCyclic(*m_currentContract))
-				m_errorReporter.typeError(
-					4224_error,
-					_memberAccess.location(),
-					"Circular reference for contract code access."
-				);
+			if (m_currentContract)
+			{
+				// TODO in the same way as with ``new``,
+				// this is not properly detecting creation-cycles if they go through
+				// internal library functions or free functions. It will be caught at
+				// code generation time, but it would of course be better to catch it here.
+
+				m_currentContract->annotation().contractDependencies.insert(&accessedContractType.contractDefinition());
+				if (contractDependenciesAreCyclic(*m_currentContract))
+					m_errorReporter.typeError(
+						4224_error,
+						_memberAccess.location(),
+						"Circular reference for contract code access."
+					);
+			}
 		}
 		else if (magicType->kind() == MagicType::Kind::MetaType && memberName == "name")
 			annotation.isPure = true;
diff --git a/libsolidity/analysis/TypeChecker.h b/libsolidity/analysis/TypeChecker.h
index e34c9e9d0..87ae1d83c 100644
--- a/libsolidity/analysis/TypeChecker.h
+++ b/libsolidity/analysis/TypeChecker.h
@@ -167,6 +167,16 @@ private:
 
 	bool experimentalFeatureActive(ExperimentalFeature _feature) const;
 
+	/// @returns the current scope that can have function or type definitions.
+	/// This is either a contract or a source unit.
+	ASTNode const* currentDefinitionScope() const
+	{
+		if (m_currentContract)
+			return m_currentContract;
+		else
+			return m_currentSourceUnit;
+	}
+
 	SourceUnit const* m_currentSourceUnit = nullptr;
 	ContractDefinition const* m_currentContract = nullptr;
 
diff --git a/libsolidity/analysis/ViewPureChecker.cpp b/libsolidity/analysis/ViewPureChecker.cpp
index a1bf31d77..1bf6028e5 100644
--- a/libsolidity/analysis/ViewPureChecker.cpp
+++ b/libsolidity/analysis/ViewPureChecker.cpp
@@ -128,30 +128,23 @@ private:
 
 bool ViewPureChecker::check()
 {
-	vector<ContractDefinition const*> contracts;
+	// Process modifiers first to infer their state mutability.
+	m_checkModifiers = true;
+	for (auto const& source: m_ast)
+		source->accept(*this);
 
-	for (auto const& node: m_ast)
-	{
-		SourceUnit const* source = dynamic_cast<SourceUnit const*>(node.get());
-		solAssert(source, "");
-		contracts += source->filteredNodes<ContractDefinition>(source->nodes());
-	}
-
-	// Check modifiers first to infer their state mutability.
-	for (auto const& contract: contracts)
-		for (ModifierDefinition const* mod: contract->functionModifiers())
-			mod->accept(*this);
-
-	for (auto const& contract: contracts)
-		contract->accept(*this);
+	m_checkModifiers = false;
+	for (auto const& source: m_ast)
+		source->accept(*this);
 
 	return !m_errors;
 }
 
-
-
 bool ViewPureChecker::visit(FunctionDefinition const& _funDef)
 {
+	if (m_checkModifiers)
+		return false;
+
 	solAssert(!m_currentFunction, "");
 	m_currentFunction = &_funDef;
 	m_bestMutabilityAndLocation = {StateMutability::Pure, _funDef.location()};
@@ -160,6 +153,9 @@ bool ViewPureChecker::visit(FunctionDefinition const& _funDef)
 
 void ViewPureChecker::endVisit(FunctionDefinition const& _funDef)
 {
+	if (m_checkModifiers)
+		return;
+
 	solAssert(m_currentFunction == &_funDef, "");
 	if (
 		m_bestMutabilityAndLocation.mutability < _funDef.stateMutability() &&
@@ -181,6 +177,9 @@ void ViewPureChecker::endVisit(FunctionDefinition const& _funDef)
 
 bool ViewPureChecker::visit(ModifierDefinition const& _modifier)
 {
+	if (!m_checkModifiers)
+		return false;
+
 	solAssert(m_currentFunction == nullptr, "");
 	m_bestMutabilityAndLocation = {StateMutability::Pure, _modifier.location()};
 	return true;
@@ -188,6 +187,9 @@ bool ViewPureChecker::visit(ModifierDefinition const& _modifier)
 
 void ViewPureChecker::endVisit(ModifierDefinition const& _modifierDef)
 {
+	if (!m_checkModifiers)
+		return;
+
 	solAssert(m_currentFunction == nullptr, "");
 	m_inferredMutability[&_modifierDef] = std::move(m_bestMutabilityAndLocation);
 }
diff --git a/libsolidity/analysis/ViewPureChecker.h b/libsolidity/analysis/ViewPureChecker.h
index 87135b4f7..62444e086 100644
--- a/libsolidity/analysis/ViewPureChecker.h
+++ b/libsolidity/analysis/ViewPureChecker.h
@@ -75,6 +75,7 @@ private:
 	langutil::ErrorReporter& m_errorReporter;
 
 	bool m_errors = false;
+	bool m_checkModifiers = false;
 	MutabilityAndLocation m_bestMutabilityAndLocation = MutabilityAndLocation{StateMutability::Payable, langutil::SourceLocation()};
 	FunctionDefinition const* m_currentFunction = nullptr;
 	std::map<ModifierDefinition const*, MutabilityAndLocation> m_inferredMutability;
diff --git a/libsolidity/ast/AST.cpp b/libsolidity/ast/AST.cpp
index 662ea81d3..621fb3936 100644
--- a/libsolidity/ast/AST.cpp
+++ b/libsolidity/ast/AST.cpp
@@ -338,7 +338,7 @@ TypePointer FunctionDefinition::type() const
 
 TypePointer FunctionDefinition::typeViaContractName() const
 {
-	if (annotation().contract->isLibrary())
+	if (libraryFunction())
 	{
 		if (isPublic())
 			return FunctionType(*this).asExternallyCallableFunction(true);
@@ -374,7 +374,9 @@ FunctionDefinition const& FunctionDefinition::resolveVirtual(
 	if (_searchStart == nullptr && !virtualSemantics())
 		return *this;
 
-	solAssert(!dynamic_cast<ContractDefinition const&>(*scope()).isLibrary(), "");
+	solAssert(!isFree(), "");
+	solAssert(isOrdinary(), "");
+	solAssert(!libraryFunction(), "");
 
 	FunctionType const* functionType = TypeProvider::function(*this)->asExternallyCallableFunction(false);
 
@@ -603,9 +605,8 @@ bool VariableDeclaration::isLibraryFunctionParameter() const
 	if (!isCallableOrCatchParameter())
 		return false;
 	if (auto const* funDef = dynamic_cast<FunctionDefinition const*>(scope()))
-		return dynamic_cast<ContractDefinition const&>(*funDef->scope()).isLibrary();
-	else
-		return false;
+		return funDef->libraryFunction();
+	return false;
 }
 
 bool VariableDeclaration::isEventParameter() const
diff --git a/libsolidity/ast/AST.h b/libsolidity/ast/AST.h
index 28d71c2b7..8b4025a45 100644
--- a/libsolidity/ast/AST.h
+++ b/libsolidity/ast/AST.h
@@ -774,6 +774,7 @@ public:
 		ASTPointer<ASTString> const& _name,
 		Visibility _visibility,
 		StateMutability _stateMutability,
+		bool _free,
 		Token _kind,
 		bool _isVirtual,
 		ASTPointer<OverrideSpecifier> const& _overrides,
@@ -787,6 +788,7 @@ public:
 		StructurallyDocumented(_documentation),
 		ImplementationOptional(_body != nullptr),
 		m_stateMutability(_stateMutability),
+		m_free(_free),
 		m_kind(_kind),
 		m_functionModifiers(std::move(_modifiers)),
 		m_body(_body)
@@ -804,6 +806,7 @@ public:
 	bool isConstructor() const { return m_kind == Token::Constructor; }
 	bool isFallback() const { return m_kind == Token::Fallback; }
 	bool isReceive() const { return m_kind == Token::Receive; }
+	bool isFree() const { return m_free; }
 	Token kind() const { return m_kind; }
 	bool isPayable() const { return m_stateMutability == StateMutability::Payable; }
 	std::vector<ASTPointer<ModifierInvocation>> const& modifiers() const { return m_functionModifiers; }
@@ -815,6 +818,7 @@ public:
 	}
 	bool isVisibleViaContractTypeAccess() const override
 	{
+		solAssert(!isFree(), "");
 		return isOrdinary() && visibility() >= Visibility::Public;
 	}
 	bool isPartOfExternalInterface() const override { return isOrdinary() && isPublic(); }
@@ -848,8 +852,12 @@ public:
 		ContractDefinition const* _searchStart = nullptr
 	) const override;
 
+protected:
+	Visibility defaultVisibility() const override { return isFree() ? Visibility::Internal : Visibility::Public; }
+
 private:
 	StateMutability m_stateMutability;
+	bool m_free;
 	Token const m_kind;
 	std::vector<ASTPointer<ModifierInvocation>> m_functionModifiers;
 	ASTPointer<Block> m_body;
diff --git a/libsolidity/ast/ASTAnnotations.h b/libsolidity/ast/ASTAnnotations.h
index 1f6e039e3..2aac79837 100644
--- a/libsolidity/ast/ASTAnnotations.h
+++ b/libsolidity/ast/ASTAnnotations.h
@@ -236,9 +236,6 @@ struct UserDefinedTypeNameAnnotation: TypeNameAnnotation
 {
 	/// Referenced declaration, set during reference resolution stage.
 	Declaration const* referencedDeclaration = nullptr;
-	/// Stores a reference to the current contract.
-	/// This is needed because types of base contracts change depending on the context.
-	ContractDefinition const* contractScope = nullptr;
 };
 
 struct ExpressionAnnotation: ASTAnnotation
diff --git a/libsolidity/ast/ASTJsonConverter.cpp b/libsolidity/ast/ASTJsonConverter.cpp
index 064068005..15ac0c620 100644
--- a/libsolidity/ast/ASTJsonConverter.cpp
+++ b/libsolidity/ast/ASTJsonConverter.cpp
@@ -361,6 +361,7 @@ bool ASTJsonConverter::visit(FunctionDefinition const& _node)
 		make_pair("name", _node.name()),
 		make_pair("documentation", _node.documentation() ? toJson(*_node.documentation()) : Json::nullValue),
 		make_pair("kind", TokenTraits::toString(_node.kind())),
+		make_pair("freeFunction", _node.isFree()),
 		make_pair("stateMutability", stateMutabilityToString(_node.stateMutability())),
 		make_pair("visibility", Declaration::visibilityToString(visibility)),
 		make_pair("virtual", _node.markedVirtual()),
@@ -467,7 +468,6 @@ bool ASTJsonConverter::visit(UserDefinedTypeName const& _node)
 	setJsonNode(_node, "UserDefinedTypeName", {
 		make_pair("name", namePathToString(_node.namePath())),
 		make_pair("referencedDeclaration", idOrNull(_node.annotation().referencedDeclaration)),
-		make_pair("contractScope", idOrNull(_node.annotation().contractScope)),
 		make_pair("typeDescriptions", typePointerToJson(_node.annotation().type, true))
 	});
 	return false;
diff --git a/libsolidity/ast/ASTJsonImporter.cpp b/libsolidity/ast/ASTJsonImporter.cpp
index 2d1fda322..8bc657abf 100644
--- a/libsolidity/ast/ASTJsonImporter.cpp
+++ b/libsolidity/ast/ASTJsonImporter.cpp
@@ -397,11 +397,25 @@ ASTPointer<FunctionDefinition> ASTJsonImporter::createFunctionDefinition(Json::V
 	std::vector<ASTPointer<ModifierInvocation>> modifiers;
 	for (auto& mod: member(_node, "modifiers"))
 		modifiers.push_back(createModifierInvocation(mod));
+
+	Visibility vis = Visibility::Default;
+	bool const freeFunction = _node.isMember("freeFunction") ? _node["freeFunction"].asBool() : false;
+	if (kind == Token::Constructor)
+	{
+	}
+	else if (freeFunction)
+		astAssert(
+			vis == Visibility::Internal || vis == Visibility::Default,
+			"Expected internal or default visibility for free function."
+		);
+	else
+		vis = visibility(_node);
 	return createASTNode<FunctionDefinition>(
 		_node,
 		memberAsASTString(_node, "name"),
-		kind == Token::Constructor ? Visibility::Default : visibility(_node),
+		vis,
 		stateMutability(_node),
+		freeFunction,
 		kind,
 		memberAsBool(_node, "virtual"),
 		_node["overrides"].isNull() ? nullptr : createOverrideSpecifier(member(_node, "overrides")),
diff --git a/libsolidity/ast/Types.cpp b/libsolidity/ast/Types.cpp
index a87ae4c3f..956412425 100644
--- a/libsolidity/ast/Types.cpp
+++ b/libsolidity/ast/Types.cpp
@@ -3151,10 +3151,8 @@ string FunctionType::toString(bool _short) const
 	{
 		auto const* functionDefinition = dynamic_cast<FunctionDefinition const*>(m_declaration);
 		solAssert(functionDefinition, "");
-		auto const* contract = dynamic_cast<ContractDefinition const*>(functionDefinition->scope());
-		solAssert(contract, "");
-		name += contract->annotation().canonicalName;
-		name += '.';
+		if (auto const* contract = dynamic_cast<ContractDefinition const*>(functionDefinition->scope()))
+			name += contract->annotation().canonicalName + ".";
 		name += functionDefinition->name();
 	}
 	name += '(';
@@ -3275,7 +3273,10 @@ FunctionTypePointer FunctionType::interfaceFunctionType() const
 {
 	// Note that m_declaration might also be a state variable!
 	solAssert(m_declaration, "Declaration needed to determine interface function type.");
-	bool isLibraryFunction = kind() != Kind::Event && dynamic_cast<ContractDefinition const&>(*m_declaration->scope()).isLibrary();
+	bool isLibraryFunction = false;
+	if (kind() != Kind::Event)
+		if (auto const* contract = dynamic_cast<ContractDefinition const*>(m_declaration->scope()))
+			isLibraryFunction = contract->isLibrary();
 
 	util::Result<TypePointers> paramTypes =
 		transformParametersToExternal(m_parameterTypes, isLibraryFunction);
@@ -3569,7 +3570,10 @@ string FunctionType::externalSignature() const
 	}
 
 	// "inLibrary" is only relevant if this is not an event.
-	bool const inLibrary = kind() != Kind::Event && dynamic_cast<ContractDefinition const&>(*m_declaration->scope()).isLibrary();
+	bool inLibrary = false;
+	if (kind() != Kind::Event)
+		if (auto const* contract = dynamic_cast<ContractDefinition const*>(m_declaration->scope()))
+			inLibrary = contract->isLibrary();
 
 	auto extParams = transformParametersToExternal(m_parameterTypes, inLibrary);
 
diff --git a/libsolidity/codegen/ExpressionCompiler.cpp b/libsolidity/codegen/ExpressionCompiler.cpp
index 8b834031f..d4f70691f 100644
--- a/libsolidity/codegen/ExpressionCompiler.cpp
+++ b/libsolidity/codegen/ExpressionCompiler.cpp
@@ -1736,9 +1736,17 @@ bool ExpressionCompiler::visit(MemberAccess const& _memberAccess)
 		Type::Category category = _memberAccess.annotation().type->category();
 		solAssert(
 			category == Type::Category::TypeType ||
-			category == Type::Category::Module,
+			category == Type::Category::Module ||
+			category == Type::Category::Function,
 			""
 		);
+		if (auto funType = dynamic_cast<FunctionType const*>(_memberAccess.annotation().type))
+		{
+			auto const* funDef = dynamic_cast<FunctionDefinition const*>(_memberAccess.annotation().referencedDeclaration);
+			solAssert(funDef && funDef->isFree(), "");
+			solAssert(funType->kind() == FunctionType::Kind::Internal, "");
+			utils().pushCombinedFunctionEntryLabel(*funDef);
+		}
 		break;
 	}
 	default:
diff --git a/libsolidity/parsing/Parser.cpp b/libsolidity/parsing/Parser.cpp
index cfb7de46e..47be4039a 100644
--- a/libsolidity/parsing/Parser.cpp
+++ b/libsolidity/parsing/Parser.cpp
@@ -107,8 +107,11 @@ ASTPointer<SourceUnit> Parser::parse(shared_ptr<Scanner> const& _scanner)
 			case Token::Enum:
 				nodes.push_back(parseEnumDefinition());
 				break;
+			case Token::Function:
+				nodes.push_back(parseFunctionDefinition(true));
+				break;
 			default:
-				fatalParserError(7858_error, "Expected pragma, import directive or contract/interface/library/struct/enum definition.");
+				fatalParserError(7858_error, "Expected pragma, import directive or contract/interface/library/struct/enum/function definition.");
 			}
 		}
 		solAssert(m_recursionDepth == 0, "");
@@ -548,7 +551,7 @@ Parser::FunctionHeaderParserResult Parser::parseFunctionHeader(bool _isStateVari
 	return result;
 }
 
-ASTPointer<ASTNode> Parser::parseFunctionDefinition()
+ASTPointer<ASTNode> Parser::parseFunctionDefinition(bool _freeFunction)
 {
 	RecursionGuard recursionGuard(*this);
 	ASTNodeFactory nodeFactory(*this);
@@ -607,6 +610,7 @@ ASTPointer<ASTNode> Parser::parseFunctionDefinition()
 		name,
 		header.visibility,
 		header.stateMutability,
+		_freeFunction,
 		kind,
 		header.isVirtual,
 		header.overrides,
diff --git a/libsolidity/parsing/Parser.h b/libsolidity/parsing/Parser.h
index b769545da..0047ed6e4 100644
--- a/libsolidity/parsing/Parser.h
+++ b/libsolidity/parsing/Parser.h
@@ -92,7 +92,7 @@ private:
 	ASTPointer<OverrideSpecifier> parseOverrideSpecifier();
 	StateMutability parseStateMutability();
 	FunctionHeaderParserResult parseFunctionHeader(bool _isStateVariable);
-	ASTPointer<ASTNode> parseFunctionDefinition();
+	ASTPointer<ASTNode> parseFunctionDefinition(bool _freeFunction = false);
 	ASTPointer<StructDefinition> parseStructDefinition();
 	ASTPointer<EnumDefinition> parseEnumDefinition();
 	ASTPointer<EnumValue> parseEnumValue();
diff --git a/test/libsolidity/semanticTests/freeFunctions/easy.sol b/test/libsolidity/semanticTests/freeFunctions/easy.sol
new file mode 100644
index 000000000..04b023d52
--- /dev/null
+++ b/test/libsolidity/semanticTests/freeFunctions/easy.sol
@@ -0,0 +1,13 @@
+function add(uint a, uint b) pure returns (uint) {
+  return a + b;
+}
+
+contract C {
+  function f(uint x) public pure returns (uint) {
+    return add(x, 2);
+  }
+}
+// ====
+// compileViaYul: also
+// ----
+// f(uint256): 7 -> 9
diff --git a/test/libsolidity/semanticTests/freeFunctions/free_runtimecode.sol b/test/libsolidity/semanticTests/freeFunctions/free_runtimecode.sol
new file mode 100644
index 000000000..7a05ff5d0
--- /dev/null
+++ b/test/libsolidity/semanticTests/freeFunctions/free_runtimecode.sol
@@ -0,0 +1,15 @@
+contract C {
+  uint public x = 2;
+}
+
+function test() returns (bool) {
+  return type(C).runtimeCode.length > 20;
+}
+
+contract D {
+  function f() public returns (bool) {
+    return test();
+  }
+}
+// ----
+// f() -> true
diff --git a/test/libsolidity/semanticTests/freeFunctions/import.sol b/test/libsolidity/semanticTests/freeFunctions/import.sol
new file mode 100644
index 000000000..edd44de49
--- /dev/null
+++ b/test/libsolidity/semanticTests/freeFunctions/import.sol
@@ -0,0 +1,18 @@
+==== Source: A ====
+struct S { uint x; }
+function set(S storage a, uint v) { a.x = v; }
+
+==== Source: B ====
+import "A";
+import "A" as A;
+contract C {
+  A.S data;
+  function f(uint v) public returns (uint one, uint two) {
+    A.set(data, v);
+    one = data.x;
+    set(data, v + 1);
+    two = data.x;
+  }
+}
+// ----
+// f(uint256): 7 -> 7, 8
diff --git a/test/libsolidity/semanticTests/freeFunctions/libraries_from_free.sol b/test/libsolidity/semanticTests/freeFunctions/libraries_from_free.sol
new file mode 100644
index 000000000..3632f6a6a
--- /dev/null
+++ b/test/libsolidity/semanticTests/freeFunctions/libraries_from_free.sol
@@ -0,0 +1,21 @@
+library L {
+  function pub() public pure returns (uint) {
+    return 7;
+  }
+  function inter() internal pure returns (uint) {
+    return 8;
+  }
+}
+
+function fu() pure returns (uint, uint) {
+  return (L.pub(), L.inter());
+}
+
+contract C {
+  function f() public pure returns (uint, uint) {
+    return fu();
+  }
+}
+// ----
+// library: L
+// f() -> 7, 8
\ No newline at end of file
diff --git a/test/libsolidity/semanticTests/freeFunctions/new_operator.sol b/test/libsolidity/semanticTests/freeFunctions/new_operator.sol
new file mode 100644
index 000000000..e35f1c9ea
--- /dev/null
+++ b/test/libsolidity/semanticTests/freeFunctions/new_operator.sol
@@ -0,0 +1,15 @@
+contract C {
+  uint public x = 2;
+}
+
+function test() returns (uint) {
+  return (new C()).x();
+}
+
+contract D {
+  function f() public returns (uint) {
+    return test();
+  }
+}
+// ----
+// f() -> 2
diff --git a/test/libsolidity/semanticTests/freeFunctions/overloads.sol b/test/libsolidity/semanticTests/freeFunctions/overloads.sol
new file mode 100644
index 000000000..9b2a914eb
--- /dev/null
+++ b/test/libsolidity/semanticTests/freeFunctions/overloads.sol
@@ -0,0 +1,16 @@
+function f(uint) returns (uint) {
+    return 2;
+}
+function f(string memory) returns (uint) {
+    return 3;
+}
+
+contract C {
+  function g() public returns (uint, uint) {
+      return (f(2), f("abc"));
+  }
+}
+// ====
+// compileViaYul: also
+// ----
+// g() -> 2, 3
diff --git a/test/libsolidity/semanticTests/freeFunctions/recursion.sol b/test/libsolidity/semanticTests/freeFunctions/recursion.sol
new file mode 100644
index 000000000..fd21fe097
--- /dev/null
+++ b/test/libsolidity/semanticTests/freeFunctions/recursion.sol
@@ -0,0 +1,23 @@
+function exp(uint base, uint exponent) pure returns (uint power) {
+    if (exponent == 0)
+        return 1;
+    power = exp(base, exponent / 2);
+    power *= power;
+    if (exponent & 1 == 1)
+        power *= base;
+}
+
+contract C {
+  function g(uint base, uint exponent) public pure returns (uint) {
+      return exp(base, exponent);
+  }
+}
+// ====
+// compileViaYul: also
+// ----
+// g(uint256,uint256): 0, 0 -> 1
+// g(uint256,uint256): 0, 1 -> 0x00
+// g(uint256,uint256): 1, 0 -> 1
+// g(uint256,uint256): 2, 3 -> 8
+// g(uint256,uint256): 3, 10 -> 59049
+// g(uint256,uint256): 2, 255 -> -57896044618658097711785492504343953926634992332820282019728792003956564819968
\ No newline at end of file
diff --git a/test/libsolidity/semanticTests/freeFunctions/storage_calldata_refs.sol b/test/libsolidity/semanticTests/freeFunctions/storage_calldata_refs.sol
new file mode 100644
index 000000000..3b94b06fc
--- /dev/null
+++ b/test/libsolidity/semanticTests/freeFunctions/storage_calldata_refs.sol
@@ -0,0 +1,17 @@
+contract C {
+    uint[] data;
+    function f(uint x, uint[] calldata input) public returns (uint, uint) {
+        data.push(x);
+        (uint a, uint[] calldata b) = fun(input, data);
+        return (a, b[1]);
+
+    }
+}
+
+function fun(uint[] calldata _x, uint[] storage _y) view  returns (uint, uint[] calldata) {
+	return (_y[0], _x);
+}
+// ====
+// compileViaYul: also
+// ----
+// f(uint256,uint256[]): 7, 0x40, 3, 8, 9, 10 -> 7, 9
diff --git a/test/libsolidity/syntaxTests/freeFunctions/free_call_via_contract_type.sol b/test/libsolidity/syntaxTests/freeFunctions/free_call_via_contract_type.sol
new file mode 100644
index 000000000..749a98d48
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/free_call_via_contract_type.sol
@@ -0,0 +1,8 @@
+contract C {
+    function f() public pure {}
+}
+function fun() {
+    C.f();
+}
+// ----
+// TypeError 3419: (68-73): Cannot call function via contract type name.
diff --git a/test/libsolidity/syntaxTests/freeFunctions/free_constructor.sol b/test/libsolidity/syntaxTests/freeFunctions/free_constructor.sol
new file mode 100644
index 000000000..afb375ca0
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/free_constructor.sol
@@ -0,0 +1,3 @@
+constructor() {}
+// ----
+// ParserError 7858: (0-11): Expected pragma, import directive or contract/interface/library/struct/enum/function definition.
diff --git a/test/libsolidity/syntaxTests/freeFunctions/free_fallback.sol b/test/libsolidity/syntaxTests/freeFunctions/free_fallback.sol
new file mode 100644
index 000000000..31b410211
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/free_fallback.sol
@@ -0,0 +1,3 @@
+fallback(){}
+// ----
+// ParserError 7858: (0-8): Expected pragma, import directive or contract/interface/library/struct/enum/function definition.
diff --git a/test/libsolidity/syntaxTests/freeFunctions/free_function_modifier.sol b/test/libsolidity/syntaxTests/freeFunctions/free_function_modifier.sol
new file mode 100644
index 000000000..dd702853a
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/free_function_modifier.sol
@@ -0,0 +1,4 @@
+function fun() someModifier {
+}
+// ----
+// DeclarationError 7576: (15-27): Undeclared identifier.
diff --git a/test/libsolidity/syntaxTests/freeFunctions/free_function_qualified_modifier.sol b/test/libsolidity/syntaxTests/freeFunctions/free_function_qualified_modifier.sol
new file mode 100644
index 000000000..779d44c72
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/free_function_qualified_modifier.sol
@@ -0,0 +1,9 @@
+contract C {
+  modifier someModifier() { _; }
+}
+
+function fun() C.someModifier {
+
+}
+// ----
+// ParserError 2314: (65-66): Expected '{' but got '.'
diff --git a/test/libsolidity/syntaxTests/freeFunctions/free_function_shadowing.sol b/test/libsolidity/syntaxTests/freeFunctions/free_function_shadowing.sol
new file mode 100644
index 000000000..bd1b2bd87
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/free_function_shadowing.sol
@@ -0,0 +1,9 @@
+function f() {}
+contract C {
+  function f() public {}
+  function g() public {
+    f();
+  }
+}
+// ----
+// Warning 2519: (31-53): This declaration shadows an existing declaration.
diff --git a/test/libsolidity/syntaxTests/freeFunctions/free_function_visibility.sol b/test/libsolidity/syntaxTests/freeFunctions/free_function_visibility.sol
new file mode 100644
index 000000000..36a0e0e0c
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/free_function_visibility.sol
@@ -0,0 +1,5 @@
+function fun1() public { }
+function fun2() internal { }
+// ----
+// SyntaxError 4126: (0-26): Free functions cannot have visibility.
+// SyntaxError 4126: (27-55): Free functions cannot have visibility.
diff --git a/test/libsolidity/syntaxTests/freeFunctions/free_function_without_body.sol b/test/libsolidity/syntaxTests/freeFunctions/free_function_without_body.sol
new file mode 100644
index 000000000..2fec9db1d
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/free_function_without_body.sol
@@ -0,0 +1,3 @@
+function f();
+// ----
+// TypeError 4668: (0-13): Free functions must be implemented.
diff --git a/test/libsolidity/syntaxTests/freeFunctions/free_functions.sol b/test/libsolidity/syntaxTests/freeFunctions/free_functions.sol
new file mode 100644
index 000000000..4862e8e63
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/free_functions.sol
@@ -0,0 +1,4 @@
+function fun(uint256, uint[] calldata _x, uint[] storage _y) view  returns (uint, uint[] calldata) {
+	return (_y[0], _x);
+}
+// ----
diff --git a/test/libsolidity/syntaxTests/freeFunctions/free_mutability.sol b/test/libsolidity/syntaxTests/freeFunctions/free_mutability.sol
new file mode 100644
index 000000000..dafa91ccb
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/free_mutability.sol
@@ -0,0 +1,8 @@
+function f() {
+    uint x = 2;
+    x;
+}
+function g(uint[] storage x) pure { x[0] = 1; }
+// ----
+// Warning 2018: (0-39): Function state mutability can be restricted to pure
+// TypeError 8961: (76-80): Function declared as pure, but this expression (potentially) modifies the state and thus requires non-payable (the default) or payable.
diff --git a/test/libsolidity/syntaxTests/freeFunctions/free_overload.sol b/test/libsolidity/syntaxTests/freeFunctions/free_overload.sol
new file mode 100644
index 000000000..440b9449f
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/free_overload.sol
@@ -0,0 +1,9 @@
+function f(uint) returns (bytes memory) {}
+function f(uint[] memory x) returns (bytes memory) { return f(x[0]); }
+function g(uint8) {}
+function g(uint16) {}
+function t() {
+    g(2);
+}
+// ----
+// TypeError 4487: (176-177): No unique declaration found after argument-dependent lookup.
diff --git a/test/libsolidity/syntaxTests/freeFunctions/free_override.sol b/test/libsolidity/syntaxTests/freeFunctions/free_override.sol
new file mode 100644
index 000000000..da54a2fa6
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/free_override.sol
@@ -0,0 +1,4 @@
+function fun() override {
+}
+// ----
+// SyntaxError 1750: (0-27): Free functions cannot override.
diff --git a/test/libsolidity/syntaxTests/freeFunctions/free_payable.sol b/test/libsolidity/syntaxTests/freeFunctions/free_payable.sol
new file mode 100644
index 000000000..563c118f0
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/free_payable.sol
@@ -0,0 +1,4 @@
+function fun() payable {
+}
+// ----
+// TypeError 9559: (0-26): Free functions cannot be payable.
diff --git a/test/libsolidity/syntaxTests/freeFunctions/free_receive.sol b/test/libsolidity/syntaxTests/freeFunctions/free_receive.sol
new file mode 100644
index 000000000..5801b9e9e
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/free_receive.sol
@@ -0,0 +1,3 @@
+receive() {}
+// ----
+// ParserError 7858: (0-7): Expected pragma, import directive or contract/interface/library/struct/enum/function definition.
diff --git a/test/libsolidity/syntaxTests/freeFunctions/free_storage.sol b/test/libsolidity/syntaxTests/freeFunctions/free_storage.sol
new file mode 100644
index 000000000..7d356a9a7
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/free_storage.sol
@@ -0,0 +1,4 @@
+struct S { uint x; }
+function fun(S storage) {
+}
+// ----
diff --git a/test/libsolidity/syntaxTests/freeFunctions/free_virtual.sol b/test/libsolidity/syntaxTests/freeFunctions/free_virtual.sol
new file mode 100644
index 000000000..a4261be1f
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/free_virtual.sol
@@ -0,0 +1,4 @@
+function fun() virtual {
+}
+// ----
+// SyntaxError 4493: (0-26): Free functions cannot be virtual.
diff --git a/test/libsolidity/syntaxTests/freeFunctions/function_same_name_as_contract.sol b/test/libsolidity/syntaxTests/freeFunctions/function_same_name_as_contract.sol
new file mode 100644
index 000000000..3b16749ae
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/function_same_name_as_contract.sol
@@ -0,0 +1,4 @@
+contract C {}
+function C() {}
+// ----
+// DeclarationError 2333: (14-29): Identifier already declared.
diff --git a/test/libsolidity/syntaxTests/freeFunctions/function_using_struct_after_contract.sol b/test/libsolidity/syntaxTests/freeFunctions/function_using_struct_after_contract.sol
new file mode 100644
index 000000000..b029c0d90
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/function_using_struct_after_contract.sol
@@ -0,0 +1,6 @@
+contract C {
+    struct S { uint x; }
+}
+function f() returns (uint) { S storage t; }
+// ----
+// DeclarationError 7920: (70-71): Identifier not found or not unique.
diff --git a/test/libsolidity/syntaxTests/freeFunctions/gas_value.sol b/test/libsolidity/syntaxTests/freeFunctions/gas_value.sol
new file mode 100644
index 000000000..7e2dafe8a
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/gas_value.sol
@@ -0,0 +1,6 @@
+function fun() {
+    fun{gas: 1}();
+    fun{value: 1}();
+}
+// ----
+// TypeError 2193: (21-32): Function call options can only be set on external function calls or contract creations.
diff --git a/test/libsolidity/syntaxTests/freeFunctions/qualified_struct_access.sol b/test/libsolidity/syntaxTests/freeFunctions/qualified_struct_access.sol
new file mode 100644
index 000000000..ab027e21d
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/qualified_struct_access.sol
@@ -0,0 +1,7 @@
+function f() returns (uint) { C.S storage t; t.x; }
+
+contract C {
+    struct S { uint x; }
+}
+// ----
+// TypeError 3464: (45-46): This variable is of storage pointer type and can be accessed without prior assignment, which would lead to undefined behaviour.
diff --git a/test/libsolidity/syntaxTests/freeFunctions/struct_after_function.sol b/test/libsolidity/syntaxTests/freeFunctions/struct_after_function.sol
new file mode 100644
index 000000000..c41693e97
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/struct_after_function.sol
@@ -0,0 +1,3 @@
+function f(S storage g) view returns (uint) { S storage t = g; return t.x; }
+struct S { uint x; }
+// ----
diff --git a/test/libsolidity/syntaxTests/freeFunctions/super_in_free_function.sol b/test/libsolidity/syntaxTests/freeFunctions/super_in_free_function.sol
new file mode 100644
index 000000000..ff6061c65
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/super_in_free_function.sol
@@ -0,0 +1,6 @@
+contract C {}
+function f() {
+    super;
+}
+// ----
+// DeclarationError 7576: (33-38): Undeclared identifier. "super" is not (or not yet) visible at this point.
diff --git a/test/libsolidity/syntaxTests/freeFunctions/this_in_free_function.sol b/test/libsolidity/syntaxTests/freeFunctions/this_in_free_function.sol
new file mode 100644
index 000000000..cdea708d4
--- /dev/null
+++ b/test/libsolidity/syntaxTests/freeFunctions/this_in_free_function.sol
@@ -0,0 +1,6 @@
+contract C {}
+function f() {
+    this;
+}
+// ----
+// DeclarationError 7576: (33-37): Undeclared identifier. "this" is not (or not yet) visible at this point.
diff --git a/test/libsolidity/syntaxTests/imports/importing_free_functions.sol b/test/libsolidity/syntaxTests/imports/importing_free_functions.sol
new file mode 100644
index 000000000..02bc3673e
--- /dev/null
+++ b/test/libsolidity/syntaxTests/imports/importing_free_functions.sol
@@ -0,0 +1,14 @@
+==== Source: a ====
+function f(uint x) pure returns (uint) { return x * 3; }
+==== Source: b ====
+import "a" as A;
+function g(uint x) pure returns (uint) { return A.f(x) * 3; }
+==== Source: c ====
+import "b" as B;
+contract C {
+    function f() public pure {
+        B.g(2);
+        B.A.f(3);
+    }
+}
+// ----

From e9f91edc4b6d1298a9ed3506c11362a714bde21f Mon Sep 17 00:00:00 2001
From: chriseth <chris@ethereum.org>
Date: Tue, 16 Jun 2020 03:35:09 +0200
Subject: [PATCH 2/5] Update existing tests.

---
 libsolidity/ast/AST.cpp                                      | 2 +-
 libsolidity/ast/AST.h                                        | 3 ---
 test/cmdlineTests/recovery_ast_constructor/output            | 2 ++
 test/cmdlineTests/recovery_ast_empty_contract/err            | 2 +-
 test/cmdlineTests/standard_only_ast_requested/output.json    | 2 +-
 test/libsolidity/ASTJSON/abstract_contract.json              | 1 +
 test/libsolidity/ASTJSON/abstract_contract_legacy.json       | 1 +
 test/libsolidity/ASTJSON/address_payable.json                | 1 +
 test/libsolidity/ASTJSON/address_payable_legacy.json         | 1 +
 test/libsolidity/ASTJSON/assembly/call.json                  | 1 +
 test/libsolidity/ASTJSON/assembly/call_legacy.json           | 1 +
 test/libsolidity/ASTJSON/assembly/empty_block.json           | 1 +
 test/libsolidity/ASTJSON/assembly/empty_block_legacy.json    | 1 +
 test/libsolidity/ASTJSON/assembly/function.json              | 1 +
 test/libsolidity/ASTJSON/assembly/function_legacy.json       | 1 +
 test/libsolidity/ASTJSON/assembly/leave.json                 | 1 +
 test/libsolidity/ASTJSON/assembly/leave_legacy.json          | 1 +
 test/libsolidity/ASTJSON/assembly/loop.json                  | 1 +
 test/libsolidity/ASTJSON/assembly/loop_legacy.json           | 1 +
 test/libsolidity/ASTJSON/assembly/nested_functions.json      | 1 +
 .../ASTJSON/assembly/nested_functions_legacy.json            | 1 +
 test/libsolidity/ASTJSON/assembly/slot_offset.json           | 1 +
 test/libsolidity/ASTJSON/assembly/slot_offset_legacy.json    | 1 +
 test/libsolidity/ASTJSON/assembly/stringlit.json             | 1 +
 test/libsolidity/ASTJSON/assembly/stringlit_legacy.json      | 1 +
 test/libsolidity/ASTJSON/assembly/switch.json                | 1 +
 test/libsolidity/ASTJSON/assembly/switch_default.json        | 1 +
 test/libsolidity/ASTJSON/assembly/switch_default_legacy.json | 1 +
 test/libsolidity/ASTJSON/assembly/switch_legacy.json         | 1 +
 test/libsolidity/ASTJSON/assembly/var_access.json            | 1 +
 test/libsolidity/ASTJSON/assembly/var_access_legacy.json     | 1 +
 test/libsolidity/ASTJSON/constructor.json                    | 1 +
 test/libsolidity/ASTJSON/constructor_legacy.json             | 1 +
 test/libsolidity/ASTJSON/documentation.json                  | 1 +
 test/libsolidity/ASTJSON/documentation_legacy.json           | 1 +
 test/libsolidity/ASTJSON/fallback.json                       | 1 +
 test/libsolidity/ASTJSON/fallback_and_reveice_ether.json     | 2 ++
 .../ASTJSON/fallback_and_reveice_ether_legacy.json           | 2 ++
 test/libsolidity/ASTJSON/fallback_legacy.json                | 1 +
 test/libsolidity/ASTJSON/fallback_payable.json               | 1 +
 test/libsolidity/ASTJSON/fallback_payable_legacy.json        | 1 +
 test/libsolidity/ASTJSON/function_type.json                  | 1 +
 test/libsolidity/ASTJSON/function_type_legacy.json           | 1 +
 .../libsolidity/ASTJSON/long_type_name_binary_operation.json | 1 +
 .../ASTJSON/long_type_name_binary_operation_legacy.json      | 1 +
 test/libsolidity/ASTJSON/long_type_name_identifier.json      | 1 +
 .../ASTJSON/long_type_name_identifier_legacy.json            | 1 +
 test/libsolidity/ASTJSON/modifier_definition.json            | 1 +
 test/libsolidity/ASTJSON/modifier_definition_legacy.json     | 1 +
 test/libsolidity/ASTJSON/modifier_invocation.json            | 1 +
 test/libsolidity/ASTJSON/modifier_invocation_legacy.json     | 1 +
 test/libsolidity/ASTJSON/non_utf8.json                       | 1 +
 test/libsolidity/ASTJSON/non_utf8_legacy.json                | 1 +
 test/libsolidity/ASTJSON/override.json                       | 5 +++++
 test/libsolidity/ASTJSON/override_legacy.json                | 5 +++++
 test/libsolidity/ASTJSON/receive_ether.json                  | 1 +
 test/libsolidity/ASTJSON/receive_ether_legacy.json           | 1 +
 test/libsolidity/ASTJSON/short_type_name.json                | 1 +
 test/libsolidity/ASTJSON/short_type_name_legacy.json         | 1 +
 test/libsolidity/ASTJSON/short_type_name_ref.json            | 1 +
 test/libsolidity/ASTJSON/short_type_name_ref_legacy.json     | 1 +
 test/libsolidity/ASTJSON/source_location.json                | 1 +
 test/libsolidity/ASTJSON/source_location_legacy.json         | 1 +
 test/libsolidity/ASTJSON/string.json                         | 1 +
 test/libsolidity/ASTJSON/string_legacy.json                  | 1 +
 test/libsolidity/ASTJSON/two_base_functions.json             | 3 +++
 test/libsolidity/ASTJSON/two_base_functions_legacy.json      | 3 +++
 test/libsolidity/ASTJSON/unicode.json                        | 1 +
 test/libsolidity/ASTJSON/unicode_legacy.json                 | 1 +
 test/libsolidity/syntaxTests/unexpected.sol                  | 2 +-
 70 files changed, 84 insertions(+), 7 deletions(-)

diff --git a/libsolidity/ast/AST.cpp b/libsolidity/ast/AST.cpp
index 621fb3936..cac28eac0 100644
--- a/libsolidity/ast/AST.cpp
+++ b/libsolidity/ast/AST.cpp
@@ -292,7 +292,7 @@ bool FunctionDefinition::libraryFunction() const
 Visibility FunctionDefinition::defaultVisibility() const
 {
 	solAssert(!isConstructor(), "");
-	return Declaration::defaultVisibility();
+	return isFree() ? Visibility::Internal : Declaration::defaultVisibility();
 }
 
 FunctionTypePointer FunctionDefinition::functionType(bool _internal) const
diff --git a/libsolidity/ast/AST.h b/libsolidity/ast/AST.h
index 8b4025a45..cfa438ce5 100644
--- a/libsolidity/ast/AST.h
+++ b/libsolidity/ast/AST.h
@@ -852,9 +852,6 @@ public:
 		ContractDefinition const* _searchStart = nullptr
 	) const override;
 
-protected:
-	Visibility defaultVisibility() const override { return isFree() ? Visibility::Internal : Visibility::Public; }
-
 private:
 	StateMutability m_stateMutability;
 	bool m_free;
diff --git a/test/cmdlineTests/recovery_ast_constructor/output b/test/cmdlineTests/recovery_ast_constructor/output
index d4a7d0288..319fb3c88 100644
--- a/test/cmdlineTests/recovery_ast_constructor/output
+++ b/test/cmdlineTests/recovery_ast_constructor/output
@@ -58,6 +58,7 @@ JSON AST:
         {
           "attributes":
           {
+            "freeFunction": false,
             "implemented": true,
             "isConstructor": true,
             "kind": "constructor",
@@ -120,6 +121,7 @@ JSON AST:
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "af11c34c",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/cmdlineTests/recovery_ast_empty_contract/err b/test/cmdlineTests/recovery_ast_empty_contract/err
index 588067877..ab976c155 100644
--- a/test/cmdlineTests/recovery_ast_empty_contract/err
+++ b/test/cmdlineTests/recovery_ast_empty_contract/err
@@ -1,4 +1,4 @@
-Error: Expected pragma, import directive or contract/interface/library/struct/enum definition.
+Error: Expected pragma, import directive or contract/interface/library/struct/enum/function definition.
  --> recovery_ast_empty_contract/input.sol:3:1:
   |
 3 | c
diff --git a/test/cmdlineTests/standard_only_ast_requested/output.json b/test/cmdlineTests/standard_only_ast_requested/output.json
index c1ffe5892..c164153ca 100644
--- a/test/cmdlineTests/standard_only_ast_requested/output.json
+++ b/test/cmdlineTests/standard_only_ast_requested/output.json
@@ -1 +1 @@
-{"sources":{"A":{"ast":{"absolutePath":"A","exportedSymbols":{"C":[6]},"id":7,"license":"GPL-3.0","nodeType":"SourceUnit","nodes":[{"id":1,"literals":["solidity",">=","0.0"],"nodeType":"PragmaDirective","src":"36:22:0"},{"abstract":false,"baseContracts":[],"contractDependencies":[],"contractKind":"contract","documentation":null,"fullyImplemented":true,"id":6,"linearizedBaseContracts":[6],"name":"C","nodeType":"ContractDefinition","nodes":[{"body":{"id":4,"nodeType":"Block","src":"97:2:0","statements":[]},"documentation":null,"functionSelector":"26121ff0","id":5,"implemented":true,"kind":"function","modifiers":[],"name":"f","nodeType":"FunctionDefinition","overrides":null,"parameters":{"id":2,"nodeType":"ParameterList","parameters":[],"src":"82:2:0"},"returnParameters":{"id":3,"nodeType":"ParameterList","parameters":[],"src":"97:0:0"},"scope":6,"src":"72:27:0","stateMutability":"pure","virtual":false,"visibility":"public"}],"scope":7,"src":"59:42:0"}],"src":"36:65:0"},"id":0}}}
+{"sources":{"A":{"ast":{"absolutePath":"A","exportedSymbols":{"C":[6]},"id":7,"license":"GPL-3.0","nodeType":"SourceUnit","nodes":[{"id":1,"literals":["solidity",">=","0.0"],"nodeType":"PragmaDirective","src":"36:22:0"},{"abstract":false,"baseContracts":[],"contractDependencies":[],"contractKind":"contract","documentation":null,"fullyImplemented":true,"id":6,"linearizedBaseContracts":[6],"name":"C","nodeType":"ContractDefinition","nodes":[{"body":{"id":4,"nodeType":"Block","src":"97:2:0","statements":[]},"documentation":null,"freeFunction":false,"functionSelector":"26121ff0","id":5,"implemented":true,"kind":"function","modifiers":[],"name":"f","nodeType":"FunctionDefinition","overrides":null,"parameters":{"id":2,"nodeType":"ParameterList","parameters":[],"src":"82:2:0"},"returnParameters":{"id":3,"nodeType":"ParameterList","parameters":[],"src":"97:0:0"},"scope":6,"src":"72:27:0","stateMutability":"pure","virtual":false,"visibility":"public"}],"scope":7,"src":"59:42:0"}],"src":"36:65:0"},"id":0}}}
diff --git a/test/libsolidity/ASTJSON/abstract_contract.json b/test/libsolidity/ASTJSON/abstract_contract.json
index 08b1e6d95..41cd1330f 100644
--- a/test/libsolidity/ASTJSON/abstract_contract.json
+++ b/test/libsolidity/ASTJSON/abstract_contract.json
@@ -34,6 +34,7 @@
             "src": "37:4:1",
             "statements": []
           },
+          "freeFunction": false,
           "id": 4,
           "implemented": true,
           "kind": "constructor",
diff --git a/test/libsolidity/ASTJSON/abstract_contract_legacy.json b/test/libsolidity/ASTJSON/abstract_contract_legacy.json
index c13abca7f..f8da2425b 100644
--- a/test/libsolidity/ASTJSON/abstract_contract_legacy.json
+++ b/test/libsolidity/ASTJSON/abstract_contract_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "implemented": true,
             "isConstructor": true,
             "kind": "constructor",
diff --git a/test/libsolidity/ASTJSON/address_payable.json b/test/libsolidity/ASTJSON/address_payable.json
index 3365ec436..8f7ca12be 100644
--- a/test/libsolidity/ASTJSON/address_payable.json
+++ b/test/libsolidity/ASTJSON/address_payable.json
@@ -462,6 +462,7 @@
               }
             ]
           },
+          "freeFunction": false,
           "functionSelector": "fc68521a",
           "id": 38,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/address_payable_legacy.json b/test/libsolidity/ASTJSON/address_payable_legacy.json
index bda50fc57..15567b5e5 100644
--- a/test/libsolidity/ASTJSON/address_payable_legacy.json
+++ b/test/libsolidity/ASTJSON/address_payable_legacy.json
@@ -91,6 +91,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "fc68521a",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/call.json b/test/libsolidity/ASTJSON/assembly/call.json
index 9538fe5cc..5fe3e3f20 100644
--- a/test/libsolidity/ASTJSON/assembly/call.json
+++ b/test/libsolidity/ASTJSON/assembly/call.json
@@ -131,6 +131,7 @@
               }
             ]
           },
+          "freeFunction": false,
           "functionSelector": "b582ec5f",
           "id": 5,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/call_legacy.json b/test/libsolidity/ASTJSON/assembly/call_legacy.json
index 2902873fa..fa9a9830b 100644
--- a/test/libsolidity/ASTJSON/assembly/call_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/call_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "b582ec5f",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/empty_block.json b/test/libsolidity/ASTJSON/assembly/empty_block.json
index 2d22cc035..18180e76b 100644
--- a/test/libsolidity/ASTJSON/assembly/empty_block.json
+++ b/test/libsolidity/ASTJSON/assembly/empty_block.json
@@ -56,6 +56,7 @@
               }
             ]
           },
+          "freeFunction": false,
           "functionSelector": "e2179b8e",
           "id": 5,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/empty_block_legacy.json b/test/libsolidity/ASTJSON/assembly/empty_block_legacy.json
index 54811bf1a..8ab74c144 100644
--- a/test/libsolidity/ASTJSON/assembly/empty_block_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/empty_block_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "e2179b8e",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/function.json b/test/libsolidity/ASTJSON/assembly/function.json
index ccbf3d853..0fc33c271 100644
--- a/test/libsolidity/ASTJSON/assembly/function.json
+++ b/test/libsolidity/ASTJSON/assembly/function.json
@@ -118,6 +118,7 @@
               }
             ]
           },
+          "freeFunction": false,
           "functionSelector": "b8c9d365",
           "id": 5,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/function_legacy.json b/test/libsolidity/ASTJSON/assembly/function_legacy.json
index 940a4b6ac..c7a928b54 100644
--- a/test/libsolidity/ASTJSON/assembly/function_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/function_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "b8c9d365",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/leave.json b/test/libsolidity/ASTJSON/assembly/leave.json
index ba765146f..7edbfe11f 100644
--- a/test/libsolidity/ASTJSON/assembly/leave.json
+++ b/test/libsolidity/ASTJSON/assembly/leave.json
@@ -68,6 +68,7 @@
               }
             ]
           },
+          "freeFunction": false,
           "functionSelector": "ece866b9",
           "id": 5,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/leave_legacy.json b/test/libsolidity/ASTJSON/assembly/leave_legacy.json
index fa71bcba0..02fba96c7 100644
--- a/test/libsolidity/ASTJSON/assembly/leave_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/leave_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "ece866b9",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/loop.json b/test/libsolidity/ASTJSON/assembly/loop.json
index 9c99cf491..f565915e8 100644
--- a/test/libsolidity/ASTJSON/assembly/loop.json
+++ b/test/libsolidity/ASTJSON/assembly/loop.json
@@ -131,6 +131,7 @@
               }
             ]
           },
+          "freeFunction": false,
           "functionSelector": "e2179b8e",
           "id": 5,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/loop_legacy.json b/test/libsolidity/ASTJSON/assembly/loop_legacy.json
index 84890475f..4f1051e03 100644
--- a/test/libsolidity/ASTJSON/assembly/loop_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/loop_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "e2179b8e",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/nested_functions.json b/test/libsolidity/ASTJSON/assembly/nested_functions.json
index f945494ba..8f9acb56f 100644
--- a/test/libsolidity/ASTJSON/assembly/nested_functions.json
+++ b/test/libsolidity/ASTJSON/assembly/nested_functions.json
@@ -95,6 +95,7 @@
               }
             ]
           },
+          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 7,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/nested_functions_legacy.json b/test/libsolidity/ASTJSON/assembly/nested_functions_legacy.json
index 393646221..2dd973e84 100644
--- a/test/libsolidity/ASTJSON/assembly/nested_functions_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/nested_functions_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/slot_offset.json b/test/libsolidity/ASTJSON/assembly/slot_offset.json
index 0858fe617..5a9b1489f 100644
--- a/test/libsolidity/ASTJSON/assembly/slot_offset.json
+++ b/test/libsolidity/ASTJSON/assembly/slot_offset.json
@@ -196,6 +196,7 @@
               }
             ]
           },
+          "freeFunction": false,
           "functionSelector": "ffae15ba",
           "id": 10,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/slot_offset_legacy.json b/test/libsolidity/ASTJSON/assembly/slot_offset_legacy.json
index 50747baaa..d84497d1a 100644
--- a/test/libsolidity/ASTJSON/assembly/slot_offset_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/slot_offset_legacy.json
@@ -112,6 +112,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "ffae15ba",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/stringlit.json b/test/libsolidity/ASTJSON/assembly/stringlit.json
index 08e0ea4f6..872e953ee 100644
--- a/test/libsolidity/ASTJSON/assembly/stringlit.json
+++ b/test/libsolidity/ASTJSON/assembly/stringlit.json
@@ -72,6 +72,7 @@
               }
             ]
           },
+          "freeFunction": false,
           "functionSelector": "5a2ee019",
           "id": 5,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/stringlit_legacy.json b/test/libsolidity/ASTJSON/assembly/stringlit_legacy.json
index 325d25274..87c79d107 100644
--- a/test/libsolidity/ASTJSON/assembly/stringlit_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/stringlit_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "5a2ee019",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/switch.json b/test/libsolidity/ASTJSON/assembly/switch.json
index 9ae71f15c..7380897a0 100644
--- a/test/libsolidity/ASTJSON/assembly/switch.json
+++ b/test/libsolidity/ASTJSON/assembly/switch.json
@@ -180,6 +180,7 @@
               }
             ]
           },
+          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 5,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/switch_default.json b/test/libsolidity/ASTJSON/assembly/switch_default.json
index 4226a8ea3..2eb2cd9dc 100644
--- a/test/libsolidity/ASTJSON/assembly/switch_default.json
+++ b/test/libsolidity/ASTJSON/assembly/switch_default.json
@@ -95,6 +95,7 @@
               }
             ]
           },
+          "freeFunction": false,
           "functionSelector": "e2179b8e",
           "id": 5,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/switch_default_legacy.json b/test/libsolidity/ASTJSON/assembly/switch_default_legacy.json
index 324330f86..5f0d10dfc 100644
--- a/test/libsolidity/ASTJSON/assembly/switch_default_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/switch_default_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "e2179b8e",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/switch_legacy.json b/test/libsolidity/ASTJSON/assembly/switch_legacy.json
index 92e2e2c61..9f907e633 100644
--- a/test/libsolidity/ASTJSON/assembly/switch_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/switch_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/var_access.json b/test/libsolidity/ASTJSON/assembly/var_access.json
index f10c45cc4..bc0a9a3c7 100644
--- a/test/libsolidity/ASTJSON/assembly/var_access.json
+++ b/test/libsolidity/ASTJSON/assembly/var_access.json
@@ -121,6 +121,7 @@
               }
             ]
           },
+          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 8,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/var_access_legacy.json b/test/libsolidity/ASTJSON/assembly/var_access_legacy.json
index fcd798ad9..2052a8aed 100644
--- a/test/libsolidity/ASTJSON/assembly/var_access_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/var_access_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/constructor.json b/test/libsolidity/ASTJSON/constructor.json
index 31747901e..c4b7e9f87 100644
--- a/test/libsolidity/ASTJSON/constructor.json
+++ b/test/libsolidity/ASTJSON/constructor.json
@@ -34,6 +34,7 @@
             "src": "28:4:1",
             "statements": []
           },
+          "freeFunction": false,
           "id": 4,
           "implemented": true,
           "kind": "constructor",
diff --git a/test/libsolidity/ASTJSON/constructor_legacy.json b/test/libsolidity/ASTJSON/constructor_legacy.json
index 68a648bc9..ade4e5629 100644
--- a/test/libsolidity/ASTJSON/constructor_legacy.json
+++ b/test/libsolidity/ASTJSON/constructor_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "implemented": true,
             "isConstructor": true,
             "kind": "constructor",
diff --git a/test/libsolidity/ASTJSON/documentation.json b/test/libsolidity/ASTJSON/documentation.json
index f0beba98f..8cf35a71e 100644
--- a/test/libsolidity/ASTJSON/documentation.json
+++ b/test/libsolidity/ASTJSON/documentation.json
@@ -216,6 +216,7 @@
             "src": "162:25:3",
             "text": "Some comment on fn."
           },
+          "freeFunction": false,
           "functionSelector": "a4a2c40b",
           "id": 22,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/documentation_legacy.json b/test/libsolidity/ASTJSON/documentation_legacy.json
index 4284c4f8f..014b70fe9 100644
--- a/test/libsolidity/ASTJSON/documentation_legacy.json
+++ b/test/libsolidity/ASTJSON/documentation_legacy.json
@@ -161,6 +161,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "a4a2c40b",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/fallback.json b/test/libsolidity/ASTJSON/fallback.json
index 7037b960a..cf706e4fe 100644
--- a/test/libsolidity/ASTJSON/fallback.json
+++ b/test/libsolidity/ASTJSON/fallback.json
@@ -34,6 +34,7 @@
             "src": "43:5:1",
             "statements": []
           },
+          "freeFunction": false,
           "id": 4,
           "implemented": true,
           "kind": "fallback",
diff --git a/test/libsolidity/ASTJSON/fallback_and_reveice_ether.json b/test/libsolidity/ASTJSON/fallback_and_reveice_ether.json
index 009363e98..e8219b6db 100644
--- a/test/libsolidity/ASTJSON/fallback_and_reveice_ether.json
+++ b/test/libsolidity/ASTJSON/fallback_and_reveice_ether.json
@@ -34,6 +34,7 @@
             "src": "42:5:1",
             "statements": []
           },
+          "freeFunction": false,
           "id": 4,
           "implemented": true,
           "kind": "receive",
@@ -68,6 +69,7 @@
             "src": "78:5:1",
             "statements": []
           },
+          "freeFunction": false,
           "id": 8,
           "implemented": true,
           "kind": "fallback",
diff --git a/test/libsolidity/ASTJSON/fallback_and_reveice_ether_legacy.json b/test/libsolidity/ASTJSON/fallback_and_reveice_ether_legacy.json
index 8ac17607e..1fa662d64 100644
--- a/test/libsolidity/ASTJSON/fallback_and_reveice_ether_legacy.json
+++ b/test/libsolidity/ASTJSON/fallback_and_reveice_ether_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "implemented": true,
             "isConstructor": false,
             "kind": "receive",
@@ -100,6 +101,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "implemented": true,
             "isConstructor": false,
             "kind": "fallback",
diff --git a/test/libsolidity/ASTJSON/fallback_legacy.json b/test/libsolidity/ASTJSON/fallback_legacy.json
index 1ee8bf6b3..9f31a225e 100644
--- a/test/libsolidity/ASTJSON/fallback_legacy.json
+++ b/test/libsolidity/ASTJSON/fallback_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "implemented": true,
             "isConstructor": false,
             "kind": "fallback",
diff --git a/test/libsolidity/ASTJSON/fallback_payable.json b/test/libsolidity/ASTJSON/fallback_payable.json
index 2391f57bb..883ba1bfd 100644
--- a/test/libsolidity/ASTJSON/fallback_payable.json
+++ b/test/libsolidity/ASTJSON/fallback_payable.json
@@ -34,6 +34,7 @@
             "src": "34:2:1",
             "statements": []
           },
+          "freeFunction": false,
           "id": 4,
           "implemented": true,
           "kind": "fallback",
diff --git a/test/libsolidity/ASTJSON/fallback_payable_legacy.json b/test/libsolidity/ASTJSON/fallback_payable_legacy.json
index 69e25ab6e..2e4a69077 100644
--- a/test/libsolidity/ASTJSON/fallback_payable_legacy.json
+++ b/test/libsolidity/ASTJSON/fallback_payable_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "implemented": true,
             "isConstructor": false,
             "kind": "fallback",
diff --git a/test/libsolidity/ASTJSON/function_type.json b/test/libsolidity/ASTJSON/function_type.json
index c0d2efc68..fb706e5e8 100644
--- a/test/libsolidity/ASTJSON/function_type.json
+++ b/test/libsolidity/ASTJSON/function_type.json
@@ -34,6 +34,7 @@
             "src": "120:2:1",
             "statements": []
           },
+          "freeFunction": false,
           "functionSelector": "d6cd4974",
           "id": 16,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/function_type_legacy.json b/test/libsolidity/ASTJSON/function_type_legacy.json
index 627ce45f0..cc02a7dd9 100644
--- a/test/libsolidity/ASTJSON/function_type_legacy.json
+++ b/test/libsolidity/ASTJSON/function_type_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "d6cd4974",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/long_type_name_binary_operation.json b/test/libsolidity/ASTJSON/long_type_name_binary_operation.json
index 7b598093b..dd9210e5f 100644
--- a/test/libsolidity/ASTJSON/long_type_name_binary_operation.json
+++ b/test/libsolidity/ASTJSON/long_type_name_binary_operation.json
@@ -134,6 +134,7 @@
               }
             ]
           },
+          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 10,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/long_type_name_binary_operation_legacy.json b/test/libsolidity/ASTJSON/long_type_name_binary_operation_legacy.json
index 46e5b0417..319b1e022 100644
--- a/test/libsolidity/ASTJSON/long_type_name_binary_operation_legacy.json
+++ b/test/libsolidity/ASTJSON/long_type_name_binary_operation_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/long_type_name_identifier.json b/test/libsolidity/ASTJSON/long_type_name_identifier.json
index 4293f6df4..6df967ea9 100644
--- a/test/libsolidity/ASTJSON/long_type_name_identifier.json
+++ b/test/libsolidity/ASTJSON/long_type_name_identifier.json
@@ -142,6 +142,7 @@
               }
             ]
           },
+          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 14,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/long_type_name_identifier_legacy.json b/test/libsolidity/ASTJSON/long_type_name_identifier_legacy.json
index ced331a6d..f6ee2b948 100644
--- a/test/libsolidity/ASTJSON/long_type_name_identifier_legacy.json
+++ b/test/libsolidity/ASTJSON/long_type_name_identifier_legacy.json
@@ -79,6 +79,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/modifier_definition.json b/test/libsolidity/ASTJSON/modifier_definition.json
index 198afe454..d1355a51f 100644
--- a/test/libsolidity/ASTJSON/modifier_definition.json
+++ b/test/libsolidity/ASTJSON/modifier_definition.json
@@ -94,6 +94,7 @@
             "src": "64:2:1",
             "statements": []
           },
+          "freeFunction": false,
           "functionSelector": "28811f59",
           "id": 13,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/modifier_definition_legacy.json b/test/libsolidity/ASTJSON/modifier_definition_legacy.json
index cc3089395..a48e02104 100644
--- a/test/libsolidity/ASTJSON/modifier_definition_legacy.json
+++ b/test/libsolidity/ASTJSON/modifier_definition_legacy.json
@@ -102,6 +102,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "28811f59",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/modifier_invocation.json b/test/libsolidity/ASTJSON/modifier_invocation.json
index 198afe454..d1355a51f 100644
--- a/test/libsolidity/ASTJSON/modifier_invocation.json
+++ b/test/libsolidity/ASTJSON/modifier_invocation.json
@@ -94,6 +94,7 @@
             "src": "64:2:1",
             "statements": []
           },
+          "freeFunction": false,
           "functionSelector": "28811f59",
           "id": 13,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/modifier_invocation_legacy.json b/test/libsolidity/ASTJSON/modifier_invocation_legacy.json
index cc3089395..a48e02104 100644
--- a/test/libsolidity/ASTJSON/modifier_invocation_legacy.json
+++ b/test/libsolidity/ASTJSON/modifier_invocation_legacy.json
@@ -102,6 +102,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "28811f59",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/non_utf8.json b/test/libsolidity/ASTJSON/non_utf8.json
index 98db4273f..22d95bf28 100644
--- a/test/libsolidity/ASTJSON/non_utf8.json
+++ b/test/libsolidity/ASTJSON/non_utf8.json
@@ -94,6 +94,7 @@
               }
             ]
           },
+          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 8,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/non_utf8_legacy.json b/test/libsolidity/ASTJSON/non_utf8_legacy.json
index d9430c82d..c8d5c312f 100644
--- a/test/libsolidity/ASTJSON/non_utf8_legacy.json
+++ b/test/libsolidity/ASTJSON/non_utf8_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/override.json b/test/libsolidity/ASTJSON/override.json
index 49f85144e..e38305bf1 100644
--- a/test/libsolidity/ASTJSON/override.json
+++ b/test/libsolidity/ASTJSON/override.json
@@ -42,6 +42,7 @@
             "src": "36:2:1",
             "statements": []
           },
+          "freeFunction": false,
           "functionSelector": "a399b6a2",
           "id": 4,
           "implemented": true,
@@ -113,6 +114,7 @@
       "nodes":
       [
         {
+          "freeFunction": false,
           "functionSelector": "c2985578",
           "id": 10,
           "implemented": false,
@@ -152,6 +154,7 @@
             "src": "115:2:1",
             "statements": []
           },
+          "freeFunction": false,
           "functionSelector": "a399b6a2",
           "id": 15,
           "implemented": true,
@@ -243,6 +246,7 @@
             "src": "170:3:1",
             "statements": []
           },
+          "freeFunction": false,
           "functionSelector": "c2985578",
           "id": 23,
           "implemented": true,
@@ -289,6 +293,7 @@
             "src": "212:2:1",
             "statements": []
           },
+          "freeFunction": false,
           "functionSelector": "a399b6a2",
           "id": 30,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/override_legacy.json b/test/libsolidity/ASTJSON/override_legacy.json
index 5cdc2f364..bbd03937f 100644
--- a/test/libsolidity/ASTJSON/override_legacy.json
+++ b/test/libsolidity/ASTJSON/override_legacy.json
@@ -46,6 +46,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "a399b6a2",
             "implemented": true,
             "isConstructor": false,
@@ -154,6 +155,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "c2985578",
             "implemented": false,
             "isConstructor": false,
@@ -208,6 +210,7 @@
             [
               4
             ],
+            "freeFunction": false,
             "functionSelector": "a399b6a2",
             "implemented": true,
             "isConstructor": false,
@@ -334,6 +337,7 @@
             [
               10
             ],
+            "freeFunction": false,
             "functionSelector": "c2985578",
             "implemented": true,
             "isConstructor": false,
@@ -413,6 +417,7 @@
             [
               15
             ],
+            "freeFunction": false,
             "functionSelector": "a399b6a2",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/receive_ether.json b/test/libsolidity/ASTJSON/receive_ether.json
index 8a1f0ac9a..8b678a593 100644
--- a/test/libsolidity/ASTJSON/receive_ether.json
+++ b/test/libsolidity/ASTJSON/receive_ether.json
@@ -34,6 +34,7 @@
             "src": "42:5:1",
             "statements": []
           },
+          "freeFunction": false,
           "id": 4,
           "implemented": true,
           "kind": "receive",
diff --git a/test/libsolidity/ASTJSON/receive_ether_legacy.json b/test/libsolidity/ASTJSON/receive_ether_legacy.json
index d9544f138..1155129d4 100644
--- a/test/libsolidity/ASTJSON/receive_ether_legacy.json
+++ b/test/libsolidity/ASTJSON/receive_ether_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "implemented": true,
             "isConstructor": false,
             "kind": "receive",
diff --git a/test/libsolidity/ASTJSON/short_type_name.json b/test/libsolidity/ASTJSON/short_type_name.json
index 882fcfe24..f569f59af 100644
--- a/test/libsolidity/ASTJSON/short_type_name.json
+++ b/test/libsolidity/ASTJSON/short_type_name.json
@@ -88,6 +88,7 @@
               }
             ]
           },
+          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 10,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/short_type_name_legacy.json b/test/libsolidity/ASTJSON/short_type_name_legacy.json
index 8e255954d..b7912f585 100644
--- a/test/libsolidity/ASTJSON/short_type_name_legacy.json
+++ b/test/libsolidity/ASTJSON/short_type_name_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/short_type_name_ref.json b/test/libsolidity/ASTJSON/short_type_name_ref.json
index 2d07a9c60..e8845981f 100644
--- a/test/libsolidity/ASTJSON/short_type_name_ref.json
+++ b/test/libsolidity/ASTJSON/short_type_name_ref.json
@@ -99,6 +99,7 @@
               }
             ]
           },
+          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 11,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/short_type_name_ref_legacy.json b/test/libsolidity/ASTJSON/short_type_name_ref_legacy.json
index 5316c56ac..f6cd04ed3 100644
--- a/test/libsolidity/ASTJSON/short_type_name_ref_legacy.json
+++ b/test/libsolidity/ASTJSON/short_type_name_ref_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/source_location.json b/test/libsolidity/ASTJSON/source_location.json
index f56231ed7..fa95c0e4a 100644
--- a/test/libsolidity/ASTJSON/source_location.json
+++ b/test/libsolidity/ASTJSON/source_location.json
@@ -131,6 +131,7 @@
               }
             ]
           },
+          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 11,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/source_location_legacy.json b/test/libsolidity/ASTJSON/source_location_legacy.json
index bf3dfaedd..529ca4444 100644
--- a/test/libsolidity/ASTJSON/source_location_legacy.json
+++ b/test/libsolidity/ASTJSON/source_location_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/string.json b/test/libsolidity/ASTJSON/string.json
index f47b41e47..41fe9fa00 100644
--- a/test/libsolidity/ASTJSON/string.json
+++ b/test/libsolidity/ASTJSON/string.json
@@ -95,6 +95,7 @@
               }
             ]
           },
+          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 8,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/string_legacy.json b/test/libsolidity/ASTJSON/string_legacy.json
index 96c984209..89c9a5e55 100644
--- a/test/libsolidity/ASTJSON/string_legacy.json
+++ b/test/libsolidity/ASTJSON/string_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/two_base_functions.json b/test/libsolidity/ASTJSON/two_base_functions.json
index 769e5c3f8..7e6526316 100644
--- a/test/libsolidity/ASTJSON/two_base_functions.json
+++ b/test/libsolidity/ASTJSON/two_base_functions.json
@@ -42,6 +42,7 @@
             "src": "45:2:1",
             "statements": []
           },
+          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 4,
           "implemented": true,
@@ -96,6 +97,7 @@
             "src": "95:2:1",
             "statements": []
           },
+          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 9,
           "implemented": true,
@@ -199,6 +201,7 @@
             "src": "160:2:1",
             "statements": []
           },
+          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 21,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/two_base_functions_legacy.json b/test/libsolidity/ASTJSON/two_base_functions_legacy.json
index a5bd2d725..405576ab6 100644
--- a/test/libsolidity/ASTJSON/two_base_functions_legacy.json
+++ b/test/libsolidity/ASTJSON/two_base_functions_legacy.json
@@ -46,6 +46,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
@@ -137,6 +138,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
@@ -272,6 +274,7 @@
               4,
               9
             ],
+            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/unicode.json b/test/libsolidity/ASTJSON/unicode.json
index 81c8ad0da..99f9eb619 100644
--- a/test/libsolidity/ASTJSON/unicode.json
+++ b/test/libsolidity/ASTJSON/unicode.json
@@ -95,6 +95,7 @@
               }
             ]
           },
+          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 8,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/unicode_legacy.json b/test/libsolidity/ASTJSON/unicode_legacy.json
index 22976f6f9..826c3ce44 100644
--- a/test/libsolidity/ASTJSON/unicode_legacy.json
+++ b/test/libsolidity/ASTJSON/unicode_legacy.json
@@ -38,6 +38,7 @@
         {
           "attributes":
           {
+            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/syntaxTests/unexpected.sol b/test/libsolidity/syntaxTests/unexpected.sol
index 79ee1b6cb..971c78000 100644
--- a/test/libsolidity/syntaxTests/unexpected.sol
+++ b/test/libsolidity/syntaxTests/unexpected.sol
@@ -1,3 +1,3 @@
 unexpected
 // ----
-// ParserError 7858: (0-10): Expected pragma, import directive or contract/interface/library/struct/enum definition.
+// ParserError 7858: (0-10): Expected pragma, import directive or contract/interface/library/struct/enum/function definition.

From cf5aa450bdbf2188a83e80221eb4a9f67b630bda Mon Sep 17 00:00:00 2001
From: chriseth <chris@ethereum.org>
Date: Tue, 16 Jun 2020 18:20:37 +0200
Subject: [PATCH 3/5] Documentation.

---
 Changelog.md                          |  1 +
 docs/Solidity.g4                      |  2 +-
 docs/contracts/function-modifiers.rst |  2 +-
 docs/contracts/functions.rst          | 28 +++++++++++++++++++++++++++
 docs/layout-of-source-files.rst       |  2 +-
 docs/structure-of-a-contract.rst      | 11 +++++++++--
 6 files changed, 41 insertions(+), 5 deletions(-)

diff --git a/Changelog.md b/Changelog.md
index 9235faf6e..4b47af706 100644
--- a/Changelog.md
+++ b/Changelog.md
@@ -1,6 +1,7 @@
 ### 0.7.1 (unreleased)
 
 Language Features:
+ * Allow function definitions outside of contracts, behaving much like internal library functions.
 
 
 Compiler Features:
diff --git a/docs/Solidity.g4 b/docs/Solidity.g4
index 91f59d78c..dee054492 100644
--- a/docs/Solidity.g4
+++ b/docs/Solidity.g4
@@ -8,7 +8,7 @@
 grammar Solidity;
 
 sourceUnit
-  : (pragmaDirective | importDirective | structDefinition | enumDefinition | contractDefinition)* EOF ;
+  : (pragmaDirective | importDirective | structDefinition | enumDefinition | functionDefinition | contractDefinition)* EOF ;
 
 pragmaDirective
   : 'pragma' pragmaName ( ~';' )* ';' ;
diff --git a/docs/contracts/function-modifiers.rst b/docs/contracts/function-modifiers.rst
index 823e6e6ac..881b8f787 100644
--- a/docs/contracts/function-modifiers.rst
+++ b/docs/contracts/function-modifiers.rst
@@ -18,7 +18,7 @@ if they are marked ``virtual``. For details, please see
 ::
 
     // SPDX-License-Identifier: GPL-3.0
-    pragma solidity >0.6.99 <0.8.0;
+    pragma solidity >0.7.0 <0.8.0;
 
     contract owned {
         constructor() { owner = msg.sender; }
diff --git a/docs/contracts/functions.rst b/docs/contracts/functions.rst
index 41174c958..e7c97c33d 100644
--- a/docs/contracts/functions.rst
+++ b/docs/contracts/functions.rst
@@ -6,6 +6,34 @@
 Functions
 *********
 
+Functions can be defined inside and outside of contracts.
+
+Functions outside of a contract, also called "free functions", always have implicit ``internal``
+:ref:`visibility<visibility-and-getters>`. Their code is included in all contracts
+that call them, similar to internal library functions.
+
+::
+
+    // SPDX-License-Identifier: GPL-3.0
+    pragma solidity >0.7.0 <0.8.0;
+
+    function sum(uint[] memory _arr) pure returns (uint s) {
+        for (uint i = 0; i < _arr.length; i++)
+            s += _arr[i];
+    }
+
+    contract ArrayExample {
+        bool found;
+        function f(uint[] memory _arr) public {
+            // This calls the free function internally.
+            // The compiler will add its code to the contract.
+            uint s = sum(_arr);
+            require(s >= 10);
+            found = true;
+        }
+    }
+
+
 .. _function-parameters-return-variables:
 
 Function Parameters and Return Variables
diff --git a/docs/layout-of-source-files.rst b/docs/layout-of-source-files.rst
index d50ea06a3..d80af49f7 100644
--- a/docs/layout-of-source-files.rst
+++ b/docs/layout-of-source-files.rst
@@ -5,7 +5,7 @@ Layout of a Solidity Source File
 Source files can contain an arbitrary number of
 :ref:`contract definitions<contract_structure>`, import_ directives,
 :ref:`pragma directives<pragma>` and
-:ref:`struct<structs>` and :ref:`enum<enums>` definitions.
+:ref:`struct<structs>`, :ref:`enum<enums>` and :ref:`function<functions>` definitions.
 
 .. index:: ! license, spdx
 
diff --git a/docs/structure-of-a-contract.rst b/docs/structure-of-a-contract.rst
index 016130730..80cd5f617 100644
--- a/docs/structure-of-a-contract.rst
+++ b/docs/structure-of-a-contract.rst
@@ -43,12 +43,14 @@ visibility.
 Functions
 =========
 
-Functions are the executable units of code within a contract.
+Functions are the executable units of code. Functions are usually
+defined inside a contract, but they can also be defined outside of
+contracts.
 
 ::
 
     // SPDX-License-Identifier: GPL-3.0
-    pragma solidity >=0.4.0 <0.8.0;
+    pragma solidity >0.7.0 <0.8.0;
 
     contract SimpleAuction {
         function bid() public payable { // Function
@@ -56,6 +58,11 @@ Functions are the executable units of code within a contract.
         }
     }
 
+    // Helper function defined outside of a contract
+    function helper(uint x) pure returns (uint) {
+        return x * 2;
+    }
+
 :ref:`function-calls` can happen internally or externally
 and have different levels of :ref:`visibility<visibility-and-getters>`
 towards other contracts. :ref:`Functions<functions>` accept :ref:`parameters and return variables<function-parameters-return-variables>` to pass parameters

From 8d92fd1c041f850d6a8f5a8c00570ea73e9a81f1 Mon Sep 17 00:00:00 2001
From: chriseth <chris@ethereum.org>
Date: Tue, 4 Aug 2020 10:38:31 +0200
Subject: [PATCH 4/5] Use opportunistic visiting order for modifiers.

---
 libsolidity/analysis/ViewPureChecker.cpp | 42 ++++++++++++------------
 libsolidity/analysis/ViewPureChecker.h   |  4 ++-
 2 files changed, 24 insertions(+), 22 deletions(-)

diff --git a/libsolidity/analysis/ViewPureChecker.cpp b/libsolidity/analysis/ViewPureChecker.cpp
index 1bf6028e5..b75b4a240 100644
--- a/libsolidity/analysis/ViewPureChecker.cpp
+++ b/libsolidity/analysis/ViewPureChecker.cpp
@@ -128,12 +128,6 @@ private:
 
 bool ViewPureChecker::check()
 {
-	// Process modifiers first to infer their state mutability.
-	m_checkModifiers = true;
-	for (auto const& source: m_ast)
-		source->accept(*this);
-
-	m_checkModifiers = false;
 	for (auto const& source: m_ast)
 		source->accept(*this);
 
@@ -142,9 +136,6 @@ bool ViewPureChecker::check()
 
 bool ViewPureChecker::visit(FunctionDefinition const& _funDef)
 {
-	if (m_checkModifiers)
-		return false;
-
 	solAssert(!m_currentFunction, "");
 	m_currentFunction = &_funDef;
 	m_bestMutabilityAndLocation = {StateMutability::Pure, _funDef.location()};
@@ -153,9 +144,6 @@ bool ViewPureChecker::visit(FunctionDefinition const& _funDef)
 
 void ViewPureChecker::endVisit(FunctionDefinition const& _funDef)
 {
-	if (m_checkModifiers)
-		return;
-
 	solAssert(m_currentFunction == &_funDef, "");
 	if (
 		m_bestMutabilityAndLocation.mutability < _funDef.stateMutability() &&
@@ -177,9 +165,6 @@ void ViewPureChecker::endVisit(FunctionDefinition const& _funDef)
 
 bool ViewPureChecker::visit(ModifierDefinition const& _modifier)
 {
-	if (!m_checkModifiers)
-		return false;
-
 	solAssert(m_currentFunction == nullptr, "");
 	m_bestMutabilityAndLocation = {StateMutability::Pure, _modifier.location()};
 	return true;
@@ -187,9 +172,6 @@ bool ViewPureChecker::visit(ModifierDefinition const& _modifier)
 
 void ViewPureChecker::endVisit(ModifierDefinition const& _modifierDef)
 {
-	if (!m_checkModifiers)
-		return;
-
 	solAssert(m_currentFunction == nullptr, "");
 	m_inferredMutability[&_modifierDef] = std::move(m_bestMutabilityAndLocation);
 }
@@ -306,7 +288,26 @@ void ViewPureChecker::reportMutability(
 		m_currentFunction->stateMutability() == StateMutability::Pure ||
 		m_currentFunction->stateMutability() == StateMutability::NonPayable,
 		""
-	);
+				);
+}
+
+ViewPureChecker::MutabilityAndLocation const& ViewPureChecker::modifierMutability(
+	ModifierDefinition const& _modifier
+)
+{
+	if (!m_inferredMutability.count(&_modifier))
+	{
+		MutabilityAndLocation bestMutabilityAndLocation{};
+		FunctionDefinition const* currentFunction = nullptr;
+		swap(bestMutabilityAndLocation, m_bestMutabilityAndLocation);
+		swap(currentFunction, m_currentFunction);
+
+		_modifier.accept(*this);
+
+		swap(bestMutabilityAndLocation, m_bestMutabilityAndLocation);
+		swap(currentFunction, m_currentFunction);
+	}
+	return m_inferredMutability.at(&_modifier);
 }
 
 void ViewPureChecker::endVisit(FunctionCall const& _functionCall)
@@ -431,8 +432,7 @@ void ViewPureChecker::endVisit(ModifierInvocation const& _modifier)
 	solAssert(_modifier.name(), "");
 	if (ModifierDefinition const* mod = dynamic_cast<decltype(mod)>(_modifier.name()->annotation().referencedDeclaration))
 	{
-		solAssert(m_inferredMutability.count(mod), "");
-		auto const& mutAndLocation = m_inferredMutability.at(mod);
+		MutabilityAndLocation const& mutAndLocation = modifierMutability(*mod);
 		reportMutability(mutAndLocation.mutability, _modifier.location(), mutAndLocation.location);
 	}
 	else
diff --git a/libsolidity/analysis/ViewPureChecker.h b/libsolidity/analysis/ViewPureChecker.h
index 62444e086..dfbb2f747 100644
--- a/libsolidity/analysis/ViewPureChecker.h
+++ b/libsolidity/analysis/ViewPureChecker.h
@@ -71,11 +71,13 @@ private:
 		std::optional<langutil::SourceLocation> const& _nestedLocation = {}
 	);
 
+	/// Determines the mutability of modifier if not already cached.
+	MutabilityAndLocation const& modifierMutability(ModifierDefinition const& _modifier);
+
 	std::vector<std::shared_ptr<ASTNode>> const& m_ast;
 	langutil::ErrorReporter& m_errorReporter;
 
 	bool m_errors = false;
-	bool m_checkModifiers = false;
 	MutabilityAndLocation m_bestMutabilityAndLocation = MutabilityAndLocation{StateMutability::Payable, langutil::SourceLocation()};
 	FunctionDefinition const* m_currentFunction = nullptr;
 	std::map<ModifierDefinition const*, MutabilityAndLocation> m_inferredMutability;

From 2ff954ec2dd00adfe511e5e9951ce230335355d4 Mon Sep 17 00:00:00 2001
From: chriseth <chris@ethereum.org>
Date: Thu, 6 Aug 2020 14:10:42 +0200
Subject: [PATCH 5/5] Use kind in json AST for free function.

---
 libsolidity/ast/ASTJsonConverter.cpp            |  3 +--
 libsolidity/ast/ASTJsonImporter.cpp             | 17 +++++++----------
 .../recovery_ast_constructor/output             |  2 --
 .../standard_only_ast_requested/output.json     |  2 +-
 test/libsolidity/ASTJSON/abstract_contract.json |  1 -
 .../ASTJSON/abstract_contract_legacy.json       |  1 -
 test/libsolidity/ASTJSON/address_payable.json   |  1 -
 .../ASTJSON/address_payable_legacy.json         |  1 -
 test/libsolidity/ASTJSON/assembly/call.json     |  1 -
 .../ASTJSON/assembly/call_legacy.json           |  1 -
 .../ASTJSON/assembly/empty_block.json           |  1 -
 .../ASTJSON/assembly/empty_block_legacy.json    |  1 -
 test/libsolidity/ASTJSON/assembly/function.json |  1 -
 .../ASTJSON/assembly/function_legacy.json       |  1 -
 test/libsolidity/ASTJSON/assembly/leave.json    |  1 -
 .../ASTJSON/assembly/leave_legacy.json          |  1 -
 test/libsolidity/ASTJSON/assembly/loop.json     |  1 -
 .../ASTJSON/assembly/loop_legacy.json           |  1 -
 .../ASTJSON/assembly/nested_functions.json      |  1 -
 .../assembly/nested_functions_legacy.json       |  1 -
 .../ASTJSON/assembly/slot_offset.json           |  1 -
 .../ASTJSON/assembly/slot_offset_legacy.json    |  1 -
 .../libsolidity/ASTJSON/assembly/stringlit.json |  1 -
 .../ASTJSON/assembly/stringlit_legacy.json      |  1 -
 test/libsolidity/ASTJSON/assembly/switch.json   |  1 -
 .../ASTJSON/assembly/switch_default.json        |  1 -
 .../ASTJSON/assembly/switch_default_legacy.json |  1 -
 .../ASTJSON/assembly/switch_legacy.json         |  1 -
 .../ASTJSON/assembly/var_access.json            |  1 -
 .../ASTJSON/assembly/var_access_legacy.json     |  1 -
 test/libsolidity/ASTJSON/constructor.json       |  1 -
 .../libsolidity/ASTJSON/constructor_legacy.json |  1 -
 test/libsolidity/ASTJSON/documentation.json     |  1 -
 .../ASTJSON/documentation_legacy.json           |  1 -
 test/libsolidity/ASTJSON/fallback.json          |  1 -
 .../ASTJSON/fallback_and_reveice_ether.json     |  2 --
 .../fallback_and_reveice_ether_legacy.json      |  2 --
 test/libsolidity/ASTJSON/fallback_legacy.json   |  1 -
 test/libsolidity/ASTJSON/fallback_payable.json  |  1 -
 .../ASTJSON/fallback_payable_legacy.json        |  1 -
 test/libsolidity/ASTJSON/function_type.json     |  1 -
 .../ASTJSON/function_type_legacy.json           |  1 -
 .../long_type_name_binary_operation.json        |  1 -
 .../long_type_name_binary_operation_legacy.json |  1 -
 .../ASTJSON/long_type_name_identifier.json      |  1 -
 .../long_type_name_identifier_legacy.json       |  1 -
 .../ASTJSON/modifier_definition.json            |  1 -
 .../ASTJSON/modifier_definition_legacy.json     |  1 -
 .../ASTJSON/modifier_invocation.json            |  1 -
 .../ASTJSON/modifier_invocation_legacy.json     |  1 -
 test/libsolidity/ASTJSON/non_utf8.json          |  1 -
 test/libsolidity/ASTJSON/non_utf8_legacy.json   |  1 -
 test/libsolidity/ASTJSON/override.json          |  5 -----
 test/libsolidity/ASTJSON/override_legacy.json   |  5 -----
 test/libsolidity/ASTJSON/receive_ether.json     |  1 -
 .../ASTJSON/receive_ether_legacy.json           |  1 -
 test/libsolidity/ASTJSON/short_type_name.json   |  1 -
 .../ASTJSON/short_type_name_legacy.json         |  1 -
 .../ASTJSON/short_type_name_ref.json            |  1 -
 .../ASTJSON/short_type_name_ref_legacy.json     |  1 -
 test/libsolidity/ASTJSON/source_location.json   |  1 -
 .../ASTJSON/source_location_legacy.json         |  1 -
 test/libsolidity/ASTJSON/string.json            |  1 -
 test/libsolidity/ASTJSON/string_legacy.json     |  1 -
 .../libsolidity/ASTJSON/two_base_functions.json |  3 ---
 .../ASTJSON/two_base_functions_legacy.json      |  3 ---
 test/libsolidity/ASTJSON/unicode.json           |  1 -
 test/libsolidity/ASTJSON/unicode_legacy.json    |  1 -
 68 files changed, 9 insertions(+), 93 deletions(-)

diff --git a/libsolidity/ast/ASTJsonConverter.cpp b/libsolidity/ast/ASTJsonConverter.cpp
index 15ac0c620..04283cc34 100644
--- a/libsolidity/ast/ASTJsonConverter.cpp
+++ b/libsolidity/ast/ASTJsonConverter.cpp
@@ -360,8 +360,7 @@ bool ASTJsonConverter::visit(FunctionDefinition const& _node)
 	std::vector<pair<string, Json::Value>> attributes = {
 		make_pair("name", _node.name()),
 		make_pair("documentation", _node.documentation() ? toJson(*_node.documentation()) : Json::nullValue),
-		make_pair("kind", TokenTraits::toString(_node.kind())),
-		make_pair("freeFunction", _node.isFree()),
+		make_pair("kind", _node.isFree() ? "freeFunction" : TokenTraits::toString(_node.kind())),
 		make_pair("stateMutability", stateMutabilityToString(_node.stateMutability())),
 		make_pair("visibility", Declaration::visibilityToString(visibility)),
 		make_pair("virtual", _node.markedVirtual()),
diff --git a/libsolidity/ast/ASTJsonImporter.cpp b/libsolidity/ast/ASTJsonImporter.cpp
index 8bc657abf..5e44b8616 100644
--- a/libsolidity/ast/ASTJsonImporter.cpp
+++ b/libsolidity/ast/ASTJsonImporter.cpp
@@ -381,6 +381,7 @@ ASTPointer<FunctionDefinition> ASTJsonImporter::createFunctionDefinition(Json::V
 	astAssert(_node["kind"].isString(), "Expected 'kind' to be a string!");
 
 	Token kind;
+	bool freeFunction = false;
 	string kindStr = member(_node, "kind").asString();
 
 	if (kindStr == "constructor")
@@ -391,6 +392,11 @@ ASTPointer<FunctionDefinition> ASTJsonImporter::createFunctionDefinition(Json::V
 		kind = Token::Fallback;
 	else if (kindStr == "receive")
 		kind = Token::Receive;
+	else if (kindStr == "freeFunction")
+	{
+		kind = Token::Function;
+		freeFunction = true;
+	}
 	else
 		astAssert(false, "Expected 'kind' to be one of [constructor, function, fallback, receive]");
 
@@ -399,16 +405,7 @@ ASTPointer<FunctionDefinition> ASTJsonImporter::createFunctionDefinition(Json::V
 		modifiers.push_back(createModifierInvocation(mod));
 
 	Visibility vis = Visibility::Default;
-	bool const freeFunction = _node.isMember("freeFunction") ? _node["freeFunction"].asBool() : false;
-	if (kind == Token::Constructor)
-	{
-	}
-	else if (freeFunction)
-		astAssert(
-			vis == Visibility::Internal || vis == Visibility::Default,
-			"Expected internal or default visibility for free function."
-		);
-	else
+	if (!freeFunction)
 		vis = visibility(_node);
 	return createASTNode<FunctionDefinition>(
 		_node,
diff --git a/test/cmdlineTests/recovery_ast_constructor/output b/test/cmdlineTests/recovery_ast_constructor/output
index 319fb3c88..d4a7d0288 100644
--- a/test/cmdlineTests/recovery_ast_constructor/output
+++ b/test/cmdlineTests/recovery_ast_constructor/output
@@ -58,7 +58,6 @@ JSON AST:
         {
           "attributes":
           {
-            "freeFunction": false,
             "implemented": true,
             "isConstructor": true,
             "kind": "constructor",
@@ -121,7 +120,6 @@ JSON AST:
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "af11c34c",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/cmdlineTests/standard_only_ast_requested/output.json b/test/cmdlineTests/standard_only_ast_requested/output.json
index c164153ca..c1ffe5892 100644
--- a/test/cmdlineTests/standard_only_ast_requested/output.json
+++ b/test/cmdlineTests/standard_only_ast_requested/output.json
@@ -1 +1 @@
-{"sources":{"A":{"ast":{"absolutePath":"A","exportedSymbols":{"C":[6]},"id":7,"license":"GPL-3.0","nodeType":"SourceUnit","nodes":[{"id":1,"literals":["solidity",">=","0.0"],"nodeType":"PragmaDirective","src":"36:22:0"},{"abstract":false,"baseContracts":[],"contractDependencies":[],"contractKind":"contract","documentation":null,"fullyImplemented":true,"id":6,"linearizedBaseContracts":[6],"name":"C","nodeType":"ContractDefinition","nodes":[{"body":{"id":4,"nodeType":"Block","src":"97:2:0","statements":[]},"documentation":null,"freeFunction":false,"functionSelector":"26121ff0","id":5,"implemented":true,"kind":"function","modifiers":[],"name":"f","nodeType":"FunctionDefinition","overrides":null,"parameters":{"id":2,"nodeType":"ParameterList","parameters":[],"src":"82:2:0"},"returnParameters":{"id":3,"nodeType":"ParameterList","parameters":[],"src":"97:0:0"},"scope":6,"src":"72:27:0","stateMutability":"pure","virtual":false,"visibility":"public"}],"scope":7,"src":"59:42:0"}],"src":"36:65:0"},"id":0}}}
+{"sources":{"A":{"ast":{"absolutePath":"A","exportedSymbols":{"C":[6]},"id":7,"license":"GPL-3.0","nodeType":"SourceUnit","nodes":[{"id":1,"literals":["solidity",">=","0.0"],"nodeType":"PragmaDirective","src":"36:22:0"},{"abstract":false,"baseContracts":[],"contractDependencies":[],"contractKind":"contract","documentation":null,"fullyImplemented":true,"id":6,"linearizedBaseContracts":[6],"name":"C","nodeType":"ContractDefinition","nodes":[{"body":{"id":4,"nodeType":"Block","src":"97:2:0","statements":[]},"documentation":null,"functionSelector":"26121ff0","id":5,"implemented":true,"kind":"function","modifiers":[],"name":"f","nodeType":"FunctionDefinition","overrides":null,"parameters":{"id":2,"nodeType":"ParameterList","parameters":[],"src":"82:2:0"},"returnParameters":{"id":3,"nodeType":"ParameterList","parameters":[],"src":"97:0:0"},"scope":6,"src":"72:27:0","stateMutability":"pure","virtual":false,"visibility":"public"}],"scope":7,"src":"59:42:0"}],"src":"36:65:0"},"id":0}}}
diff --git a/test/libsolidity/ASTJSON/abstract_contract.json b/test/libsolidity/ASTJSON/abstract_contract.json
index 41cd1330f..08b1e6d95 100644
--- a/test/libsolidity/ASTJSON/abstract_contract.json
+++ b/test/libsolidity/ASTJSON/abstract_contract.json
@@ -34,7 +34,6 @@
             "src": "37:4:1",
             "statements": []
           },
-          "freeFunction": false,
           "id": 4,
           "implemented": true,
           "kind": "constructor",
diff --git a/test/libsolidity/ASTJSON/abstract_contract_legacy.json b/test/libsolidity/ASTJSON/abstract_contract_legacy.json
index f8da2425b..c13abca7f 100644
--- a/test/libsolidity/ASTJSON/abstract_contract_legacy.json
+++ b/test/libsolidity/ASTJSON/abstract_contract_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "implemented": true,
             "isConstructor": true,
             "kind": "constructor",
diff --git a/test/libsolidity/ASTJSON/address_payable.json b/test/libsolidity/ASTJSON/address_payable.json
index 8f7ca12be..3365ec436 100644
--- a/test/libsolidity/ASTJSON/address_payable.json
+++ b/test/libsolidity/ASTJSON/address_payable.json
@@ -462,7 +462,6 @@
               }
             ]
           },
-          "freeFunction": false,
           "functionSelector": "fc68521a",
           "id": 38,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/address_payable_legacy.json b/test/libsolidity/ASTJSON/address_payable_legacy.json
index 15567b5e5..bda50fc57 100644
--- a/test/libsolidity/ASTJSON/address_payable_legacy.json
+++ b/test/libsolidity/ASTJSON/address_payable_legacy.json
@@ -91,7 +91,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "fc68521a",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/call.json b/test/libsolidity/ASTJSON/assembly/call.json
index 5fe3e3f20..9538fe5cc 100644
--- a/test/libsolidity/ASTJSON/assembly/call.json
+++ b/test/libsolidity/ASTJSON/assembly/call.json
@@ -131,7 +131,6 @@
               }
             ]
           },
-          "freeFunction": false,
           "functionSelector": "b582ec5f",
           "id": 5,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/call_legacy.json b/test/libsolidity/ASTJSON/assembly/call_legacy.json
index fa9a9830b..2902873fa 100644
--- a/test/libsolidity/ASTJSON/assembly/call_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/call_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "b582ec5f",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/empty_block.json b/test/libsolidity/ASTJSON/assembly/empty_block.json
index 18180e76b..2d22cc035 100644
--- a/test/libsolidity/ASTJSON/assembly/empty_block.json
+++ b/test/libsolidity/ASTJSON/assembly/empty_block.json
@@ -56,7 +56,6 @@
               }
             ]
           },
-          "freeFunction": false,
           "functionSelector": "e2179b8e",
           "id": 5,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/empty_block_legacy.json b/test/libsolidity/ASTJSON/assembly/empty_block_legacy.json
index 8ab74c144..54811bf1a 100644
--- a/test/libsolidity/ASTJSON/assembly/empty_block_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/empty_block_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "e2179b8e",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/function.json b/test/libsolidity/ASTJSON/assembly/function.json
index 0fc33c271..ccbf3d853 100644
--- a/test/libsolidity/ASTJSON/assembly/function.json
+++ b/test/libsolidity/ASTJSON/assembly/function.json
@@ -118,7 +118,6 @@
               }
             ]
           },
-          "freeFunction": false,
           "functionSelector": "b8c9d365",
           "id": 5,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/function_legacy.json b/test/libsolidity/ASTJSON/assembly/function_legacy.json
index c7a928b54..940a4b6ac 100644
--- a/test/libsolidity/ASTJSON/assembly/function_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/function_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "b8c9d365",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/leave.json b/test/libsolidity/ASTJSON/assembly/leave.json
index 7edbfe11f..ba765146f 100644
--- a/test/libsolidity/ASTJSON/assembly/leave.json
+++ b/test/libsolidity/ASTJSON/assembly/leave.json
@@ -68,7 +68,6 @@
               }
             ]
           },
-          "freeFunction": false,
           "functionSelector": "ece866b9",
           "id": 5,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/leave_legacy.json b/test/libsolidity/ASTJSON/assembly/leave_legacy.json
index 02fba96c7..fa71bcba0 100644
--- a/test/libsolidity/ASTJSON/assembly/leave_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/leave_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "ece866b9",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/loop.json b/test/libsolidity/ASTJSON/assembly/loop.json
index f565915e8..9c99cf491 100644
--- a/test/libsolidity/ASTJSON/assembly/loop.json
+++ b/test/libsolidity/ASTJSON/assembly/loop.json
@@ -131,7 +131,6 @@
               }
             ]
           },
-          "freeFunction": false,
           "functionSelector": "e2179b8e",
           "id": 5,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/loop_legacy.json b/test/libsolidity/ASTJSON/assembly/loop_legacy.json
index 4f1051e03..84890475f 100644
--- a/test/libsolidity/ASTJSON/assembly/loop_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/loop_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "e2179b8e",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/nested_functions.json b/test/libsolidity/ASTJSON/assembly/nested_functions.json
index 8f9acb56f..f945494ba 100644
--- a/test/libsolidity/ASTJSON/assembly/nested_functions.json
+++ b/test/libsolidity/ASTJSON/assembly/nested_functions.json
@@ -95,7 +95,6 @@
               }
             ]
           },
-          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 7,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/nested_functions_legacy.json b/test/libsolidity/ASTJSON/assembly/nested_functions_legacy.json
index 2dd973e84..393646221 100644
--- a/test/libsolidity/ASTJSON/assembly/nested_functions_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/nested_functions_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/slot_offset.json b/test/libsolidity/ASTJSON/assembly/slot_offset.json
index 5a9b1489f..0858fe617 100644
--- a/test/libsolidity/ASTJSON/assembly/slot_offset.json
+++ b/test/libsolidity/ASTJSON/assembly/slot_offset.json
@@ -196,7 +196,6 @@
               }
             ]
           },
-          "freeFunction": false,
           "functionSelector": "ffae15ba",
           "id": 10,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/slot_offset_legacy.json b/test/libsolidity/ASTJSON/assembly/slot_offset_legacy.json
index d84497d1a..50747baaa 100644
--- a/test/libsolidity/ASTJSON/assembly/slot_offset_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/slot_offset_legacy.json
@@ -112,7 +112,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "ffae15ba",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/stringlit.json b/test/libsolidity/ASTJSON/assembly/stringlit.json
index 872e953ee..08e0ea4f6 100644
--- a/test/libsolidity/ASTJSON/assembly/stringlit.json
+++ b/test/libsolidity/ASTJSON/assembly/stringlit.json
@@ -72,7 +72,6 @@
               }
             ]
           },
-          "freeFunction": false,
           "functionSelector": "5a2ee019",
           "id": 5,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/stringlit_legacy.json b/test/libsolidity/ASTJSON/assembly/stringlit_legacy.json
index 87c79d107..325d25274 100644
--- a/test/libsolidity/ASTJSON/assembly/stringlit_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/stringlit_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "5a2ee019",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/switch.json b/test/libsolidity/ASTJSON/assembly/switch.json
index 7380897a0..9ae71f15c 100644
--- a/test/libsolidity/ASTJSON/assembly/switch.json
+++ b/test/libsolidity/ASTJSON/assembly/switch.json
@@ -180,7 +180,6 @@
               }
             ]
           },
-          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 5,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/switch_default.json b/test/libsolidity/ASTJSON/assembly/switch_default.json
index 2eb2cd9dc..4226a8ea3 100644
--- a/test/libsolidity/ASTJSON/assembly/switch_default.json
+++ b/test/libsolidity/ASTJSON/assembly/switch_default.json
@@ -95,7 +95,6 @@
               }
             ]
           },
-          "freeFunction": false,
           "functionSelector": "e2179b8e",
           "id": 5,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/switch_default_legacy.json b/test/libsolidity/ASTJSON/assembly/switch_default_legacy.json
index 5f0d10dfc..324330f86 100644
--- a/test/libsolidity/ASTJSON/assembly/switch_default_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/switch_default_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "e2179b8e",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/switch_legacy.json b/test/libsolidity/ASTJSON/assembly/switch_legacy.json
index 9f907e633..92e2e2c61 100644
--- a/test/libsolidity/ASTJSON/assembly/switch_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/switch_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/assembly/var_access.json b/test/libsolidity/ASTJSON/assembly/var_access.json
index bc0a9a3c7..f10c45cc4 100644
--- a/test/libsolidity/ASTJSON/assembly/var_access.json
+++ b/test/libsolidity/ASTJSON/assembly/var_access.json
@@ -121,7 +121,6 @@
               }
             ]
           },
-          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 8,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/assembly/var_access_legacy.json b/test/libsolidity/ASTJSON/assembly/var_access_legacy.json
index 2052a8aed..fcd798ad9 100644
--- a/test/libsolidity/ASTJSON/assembly/var_access_legacy.json
+++ b/test/libsolidity/ASTJSON/assembly/var_access_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/constructor.json b/test/libsolidity/ASTJSON/constructor.json
index c4b7e9f87..31747901e 100644
--- a/test/libsolidity/ASTJSON/constructor.json
+++ b/test/libsolidity/ASTJSON/constructor.json
@@ -34,7 +34,6 @@
             "src": "28:4:1",
             "statements": []
           },
-          "freeFunction": false,
           "id": 4,
           "implemented": true,
           "kind": "constructor",
diff --git a/test/libsolidity/ASTJSON/constructor_legacy.json b/test/libsolidity/ASTJSON/constructor_legacy.json
index ade4e5629..68a648bc9 100644
--- a/test/libsolidity/ASTJSON/constructor_legacy.json
+++ b/test/libsolidity/ASTJSON/constructor_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "implemented": true,
             "isConstructor": true,
             "kind": "constructor",
diff --git a/test/libsolidity/ASTJSON/documentation.json b/test/libsolidity/ASTJSON/documentation.json
index 8cf35a71e..f0beba98f 100644
--- a/test/libsolidity/ASTJSON/documentation.json
+++ b/test/libsolidity/ASTJSON/documentation.json
@@ -216,7 +216,6 @@
             "src": "162:25:3",
             "text": "Some comment on fn."
           },
-          "freeFunction": false,
           "functionSelector": "a4a2c40b",
           "id": 22,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/documentation_legacy.json b/test/libsolidity/ASTJSON/documentation_legacy.json
index 014b70fe9..4284c4f8f 100644
--- a/test/libsolidity/ASTJSON/documentation_legacy.json
+++ b/test/libsolidity/ASTJSON/documentation_legacy.json
@@ -161,7 +161,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "a4a2c40b",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/fallback.json b/test/libsolidity/ASTJSON/fallback.json
index cf706e4fe..7037b960a 100644
--- a/test/libsolidity/ASTJSON/fallback.json
+++ b/test/libsolidity/ASTJSON/fallback.json
@@ -34,7 +34,6 @@
             "src": "43:5:1",
             "statements": []
           },
-          "freeFunction": false,
           "id": 4,
           "implemented": true,
           "kind": "fallback",
diff --git a/test/libsolidity/ASTJSON/fallback_and_reveice_ether.json b/test/libsolidity/ASTJSON/fallback_and_reveice_ether.json
index e8219b6db..009363e98 100644
--- a/test/libsolidity/ASTJSON/fallback_and_reveice_ether.json
+++ b/test/libsolidity/ASTJSON/fallback_and_reveice_ether.json
@@ -34,7 +34,6 @@
             "src": "42:5:1",
             "statements": []
           },
-          "freeFunction": false,
           "id": 4,
           "implemented": true,
           "kind": "receive",
@@ -69,7 +68,6 @@
             "src": "78:5:1",
             "statements": []
           },
-          "freeFunction": false,
           "id": 8,
           "implemented": true,
           "kind": "fallback",
diff --git a/test/libsolidity/ASTJSON/fallback_and_reveice_ether_legacy.json b/test/libsolidity/ASTJSON/fallback_and_reveice_ether_legacy.json
index 1fa662d64..8ac17607e 100644
--- a/test/libsolidity/ASTJSON/fallback_and_reveice_ether_legacy.json
+++ b/test/libsolidity/ASTJSON/fallback_and_reveice_ether_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "implemented": true,
             "isConstructor": false,
             "kind": "receive",
@@ -101,7 +100,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "implemented": true,
             "isConstructor": false,
             "kind": "fallback",
diff --git a/test/libsolidity/ASTJSON/fallback_legacy.json b/test/libsolidity/ASTJSON/fallback_legacy.json
index 9f31a225e..1ee8bf6b3 100644
--- a/test/libsolidity/ASTJSON/fallback_legacy.json
+++ b/test/libsolidity/ASTJSON/fallback_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "implemented": true,
             "isConstructor": false,
             "kind": "fallback",
diff --git a/test/libsolidity/ASTJSON/fallback_payable.json b/test/libsolidity/ASTJSON/fallback_payable.json
index 883ba1bfd..2391f57bb 100644
--- a/test/libsolidity/ASTJSON/fallback_payable.json
+++ b/test/libsolidity/ASTJSON/fallback_payable.json
@@ -34,7 +34,6 @@
             "src": "34:2:1",
             "statements": []
           },
-          "freeFunction": false,
           "id": 4,
           "implemented": true,
           "kind": "fallback",
diff --git a/test/libsolidity/ASTJSON/fallback_payable_legacy.json b/test/libsolidity/ASTJSON/fallback_payable_legacy.json
index 2e4a69077..69e25ab6e 100644
--- a/test/libsolidity/ASTJSON/fallback_payable_legacy.json
+++ b/test/libsolidity/ASTJSON/fallback_payable_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "implemented": true,
             "isConstructor": false,
             "kind": "fallback",
diff --git a/test/libsolidity/ASTJSON/function_type.json b/test/libsolidity/ASTJSON/function_type.json
index fb706e5e8..c0d2efc68 100644
--- a/test/libsolidity/ASTJSON/function_type.json
+++ b/test/libsolidity/ASTJSON/function_type.json
@@ -34,7 +34,6 @@
             "src": "120:2:1",
             "statements": []
           },
-          "freeFunction": false,
           "functionSelector": "d6cd4974",
           "id": 16,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/function_type_legacy.json b/test/libsolidity/ASTJSON/function_type_legacy.json
index cc02a7dd9..627ce45f0 100644
--- a/test/libsolidity/ASTJSON/function_type_legacy.json
+++ b/test/libsolidity/ASTJSON/function_type_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "d6cd4974",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/long_type_name_binary_operation.json b/test/libsolidity/ASTJSON/long_type_name_binary_operation.json
index dd9210e5f..7b598093b 100644
--- a/test/libsolidity/ASTJSON/long_type_name_binary_operation.json
+++ b/test/libsolidity/ASTJSON/long_type_name_binary_operation.json
@@ -134,7 +134,6 @@
               }
             ]
           },
-          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 10,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/long_type_name_binary_operation_legacy.json b/test/libsolidity/ASTJSON/long_type_name_binary_operation_legacy.json
index 319b1e022..46e5b0417 100644
--- a/test/libsolidity/ASTJSON/long_type_name_binary_operation_legacy.json
+++ b/test/libsolidity/ASTJSON/long_type_name_binary_operation_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/long_type_name_identifier.json b/test/libsolidity/ASTJSON/long_type_name_identifier.json
index 6df967ea9..4293f6df4 100644
--- a/test/libsolidity/ASTJSON/long_type_name_identifier.json
+++ b/test/libsolidity/ASTJSON/long_type_name_identifier.json
@@ -142,7 +142,6 @@
               }
             ]
           },
-          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 14,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/long_type_name_identifier_legacy.json b/test/libsolidity/ASTJSON/long_type_name_identifier_legacy.json
index f6ee2b948..ced331a6d 100644
--- a/test/libsolidity/ASTJSON/long_type_name_identifier_legacy.json
+++ b/test/libsolidity/ASTJSON/long_type_name_identifier_legacy.json
@@ -79,7 +79,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/modifier_definition.json b/test/libsolidity/ASTJSON/modifier_definition.json
index d1355a51f..198afe454 100644
--- a/test/libsolidity/ASTJSON/modifier_definition.json
+++ b/test/libsolidity/ASTJSON/modifier_definition.json
@@ -94,7 +94,6 @@
             "src": "64:2:1",
             "statements": []
           },
-          "freeFunction": false,
           "functionSelector": "28811f59",
           "id": 13,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/modifier_definition_legacy.json b/test/libsolidity/ASTJSON/modifier_definition_legacy.json
index a48e02104..cc3089395 100644
--- a/test/libsolidity/ASTJSON/modifier_definition_legacy.json
+++ b/test/libsolidity/ASTJSON/modifier_definition_legacy.json
@@ -102,7 +102,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "28811f59",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/modifier_invocation.json b/test/libsolidity/ASTJSON/modifier_invocation.json
index d1355a51f..198afe454 100644
--- a/test/libsolidity/ASTJSON/modifier_invocation.json
+++ b/test/libsolidity/ASTJSON/modifier_invocation.json
@@ -94,7 +94,6 @@
             "src": "64:2:1",
             "statements": []
           },
-          "freeFunction": false,
           "functionSelector": "28811f59",
           "id": 13,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/modifier_invocation_legacy.json b/test/libsolidity/ASTJSON/modifier_invocation_legacy.json
index a48e02104..cc3089395 100644
--- a/test/libsolidity/ASTJSON/modifier_invocation_legacy.json
+++ b/test/libsolidity/ASTJSON/modifier_invocation_legacy.json
@@ -102,7 +102,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "28811f59",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/non_utf8.json b/test/libsolidity/ASTJSON/non_utf8.json
index 22d95bf28..98db4273f 100644
--- a/test/libsolidity/ASTJSON/non_utf8.json
+++ b/test/libsolidity/ASTJSON/non_utf8.json
@@ -94,7 +94,6 @@
               }
             ]
           },
-          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 8,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/non_utf8_legacy.json b/test/libsolidity/ASTJSON/non_utf8_legacy.json
index c8d5c312f..d9430c82d 100644
--- a/test/libsolidity/ASTJSON/non_utf8_legacy.json
+++ b/test/libsolidity/ASTJSON/non_utf8_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/override.json b/test/libsolidity/ASTJSON/override.json
index e38305bf1..49f85144e 100644
--- a/test/libsolidity/ASTJSON/override.json
+++ b/test/libsolidity/ASTJSON/override.json
@@ -42,7 +42,6 @@
             "src": "36:2:1",
             "statements": []
           },
-          "freeFunction": false,
           "functionSelector": "a399b6a2",
           "id": 4,
           "implemented": true,
@@ -114,7 +113,6 @@
       "nodes":
       [
         {
-          "freeFunction": false,
           "functionSelector": "c2985578",
           "id": 10,
           "implemented": false,
@@ -154,7 +152,6 @@
             "src": "115:2:1",
             "statements": []
           },
-          "freeFunction": false,
           "functionSelector": "a399b6a2",
           "id": 15,
           "implemented": true,
@@ -246,7 +243,6 @@
             "src": "170:3:1",
             "statements": []
           },
-          "freeFunction": false,
           "functionSelector": "c2985578",
           "id": 23,
           "implemented": true,
@@ -293,7 +289,6 @@
             "src": "212:2:1",
             "statements": []
           },
-          "freeFunction": false,
           "functionSelector": "a399b6a2",
           "id": 30,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/override_legacy.json b/test/libsolidity/ASTJSON/override_legacy.json
index bbd03937f..5cdc2f364 100644
--- a/test/libsolidity/ASTJSON/override_legacy.json
+++ b/test/libsolidity/ASTJSON/override_legacy.json
@@ -46,7 +46,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "a399b6a2",
             "implemented": true,
             "isConstructor": false,
@@ -155,7 +154,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "c2985578",
             "implemented": false,
             "isConstructor": false,
@@ -210,7 +208,6 @@
             [
               4
             ],
-            "freeFunction": false,
             "functionSelector": "a399b6a2",
             "implemented": true,
             "isConstructor": false,
@@ -337,7 +334,6 @@
             [
               10
             ],
-            "freeFunction": false,
             "functionSelector": "c2985578",
             "implemented": true,
             "isConstructor": false,
@@ -417,7 +413,6 @@
             [
               15
             ],
-            "freeFunction": false,
             "functionSelector": "a399b6a2",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/receive_ether.json b/test/libsolidity/ASTJSON/receive_ether.json
index 8b678a593..8a1f0ac9a 100644
--- a/test/libsolidity/ASTJSON/receive_ether.json
+++ b/test/libsolidity/ASTJSON/receive_ether.json
@@ -34,7 +34,6 @@
             "src": "42:5:1",
             "statements": []
           },
-          "freeFunction": false,
           "id": 4,
           "implemented": true,
           "kind": "receive",
diff --git a/test/libsolidity/ASTJSON/receive_ether_legacy.json b/test/libsolidity/ASTJSON/receive_ether_legacy.json
index 1155129d4..d9544f138 100644
--- a/test/libsolidity/ASTJSON/receive_ether_legacy.json
+++ b/test/libsolidity/ASTJSON/receive_ether_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "implemented": true,
             "isConstructor": false,
             "kind": "receive",
diff --git a/test/libsolidity/ASTJSON/short_type_name.json b/test/libsolidity/ASTJSON/short_type_name.json
index f569f59af..882fcfe24 100644
--- a/test/libsolidity/ASTJSON/short_type_name.json
+++ b/test/libsolidity/ASTJSON/short_type_name.json
@@ -88,7 +88,6 @@
               }
             ]
           },
-          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 10,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/short_type_name_legacy.json b/test/libsolidity/ASTJSON/short_type_name_legacy.json
index b7912f585..8e255954d 100644
--- a/test/libsolidity/ASTJSON/short_type_name_legacy.json
+++ b/test/libsolidity/ASTJSON/short_type_name_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/short_type_name_ref.json b/test/libsolidity/ASTJSON/short_type_name_ref.json
index e8845981f..2d07a9c60 100644
--- a/test/libsolidity/ASTJSON/short_type_name_ref.json
+++ b/test/libsolidity/ASTJSON/short_type_name_ref.json
@@ -99,7 +99,6 @@
               }
             ]
           },
-          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 11,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/short_type_name_ref_legacy.json b/test/libsolidity/ASTJSON/short_type_name_ref_legacy.json
index f6cd04ed3..5316c56ac 100644
--- a/test/libsolidity/ASTJSON/short_type_name_ref_legacy.json
+++ b/test/libsolidity/ASTJSON/short_type_name_ref_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/source_location.json b/test/libsolidity/ASTJSON/source_location.json
index fa95c0e4a..f56231ed7 100644
--- a/test/libsolidity/ASTJSON/source_location.json
+++ b/test/libsolidity/ASTJSON/source_location.json
@@ -131,7 +131,6 @@
               }
             ]
           },
-          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 11,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/source_location_legacy.json b/test/libsolidity/ASTJSON/source_location_legacy.json
index 529ca4444..bf3dfaedd 100644
--- a/test/libsolidity/ASTJSON/source_location_legacy.json
+++ b/test/libsolidity/ASTJSON/source_location_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/string.json b/test/libsolidity/ASTJSON/string.json
index 41fe9fa00..f47b41e47 100644
--- a/test/libsolidity/ASTJSON/string.json
+++ b/test/libsolidity/ASTJSON/string.json
@@ -95,7 +95,6 @@
               }
             ]
           },
-          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 8,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/string_legacy.json b/test/libsolidity/ASTJSON/string_legacy.json
index 89c9a5e55..96c984209 100644
--- a/test/libsolidity/ASTJSON/string_legacy.json
+++ b/test/libsolidity/ASTJSON/string_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/two_base_functions.json b/test/libsolidity/ASTJSON/two_base_functions.json
index 7e6526316..769e5c3f8 100644
--- a/test/libsolidity/ASTJSON/two_base_functions.json
+++ b/test/libsolidity/ASTJSON/two_base_functions.json
@@ -42,7 +42,6 @@
             "src": "45:2:1",
             "statements": []
           },
-          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 4,
           "implemented": true,
@@ -97,7 +96,6 @@
             "src": "95:2:1",
             "statements": []
           },
-          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 9,
           "implemented": true,
@@ -201,7 +199,6 @@
             "src": "160:2:1",
             "statements": []
           },
-          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 21,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/two_base_functions_legacy.json b/test/libsolidity/ASTJSON/two_base_functions_legacy.json
index 405576ab6..a5bd2d725 100644
--- a/test/libsolidity/ASTJSON/two_base_functions_legacy.json
+++ b/test/libsolidity/ASTJSON/two_base_functions_legacy.json
@@ -46,7 +46,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
@@ -138,7 +137,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
@@ -274,7 +272,6 @@
               4,
               9
             ],
-            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,
diff --git a/test/libsolidity/ASTJSON/unicode.json b/test/libsolidity/ASTJSON/unicode.json
index 99f9eb619..81c8ad0da 100644
--- a/test/libsolidity/ASTJSON/unicode.json
+++ b/test/libsolidity/ASTJSON/unicode.json
@@ -95,7 +95,6 @@
               }
             ]
           },
-          "freeFunction": false,
           "functionSelector": "26121ff0",
           "id": 8,
           "implemented": true,
diff --git a/test/libsolidity/ASTJSON/unicode_legacy.json b/test/libsolidity/ASTJSON/unicode_legacy.json
index 826c3ce44..22976f6f9 100644
--- a/test/libsolidity/ASTJSON/unicode_legacy.json
+++ b/test/libsolidity/ASTJSON/unicode_legacy.json
@@ -38,7 +38,6 @@
         {
           "attributes":
           {
-            "freeFunction": false,
             "functionSelector": "26121ff0",
             "implemented": true,
             "isConstructor": false,