Merge branch 'develop' into anurag_issue_3667

libsolidity/analysis/ControlFlowAnalyzer.cpp

@@ -75,7 +75,10 @@ void ControlFlowAnalyzer::checkUnassignedStorageReturnValues(
 	{
 		auto& unassignedAtFunctionEntry = unassigned[_functionEntry];
 		for (auto const& returnParameter: _function.returnParameterList()->parameters())
-			if (returnParameter->type()->dataStoredIn(DataLocation::Storage))
+			if (
+				returnParameter->type()->dataStoredIn(DataLocation::Storage) ||
+				returnParameter->type()->category() == Type::Category::Mapping
+			)
 				unassignedAtFunctionEntry.insert(returnParameter.get());
 	}
 

libsolidity/analysis/DeclarationContainer.cpp

@@ -138,19 +138,22 @@ vector<Declaration const*> DeclarationContainer::resolveName(ASTString const& _n
 vector<ASTString> DeclarationContainer::similarNames(ASTString const& _name) const
 {
 	static size_t const MAXIMUM_EDIT_DISTANCE = 2;
+	// because the function below has quadratic runtime - it will not magically improve once a better algorithm is discovered ;)
+	// since 80 is the suggested line length limit, we use 80^2 as length threshold
+	static size_t const MAXIMUM_LENGTH_THRESHOLD = 80 * 80;
 
 	vector<ASTString> similar;
 
 	for (auto const& declaration: m_declarations)
 	{
 		string const& declarationName = declaration.first;
-		if (stringWithinDistance(_name, declarationName, MAXIMUM_EDIT_DISTANCE))
+		if (stringWithinDistance(_name, declarationName, MAXIMUM_EDIT_DISTANCE, MAXIMUM_LENGTH_THRESHOLD))
 			similar.push_back(declarationName);
 	}
 	for (auto const& declaration: m_invisibleDeclarations)
 	{
 		string const& declarationName = declaration.first;
-		if (stringWithinDistance(_name, declarationName, MAXIMUM_EDIT_DISTANCE))
+		if (stringWithinDistance(_name, declarationName, MAXIMUM_EDIT_DISTANCE, MAXIMUM_LENGTH_THRESHOLD))
 			similar.push_back(declarationName);
 	}
 

libsolidity/analysis/DocStringAnalyser.cpp

@@ -48,7 +48,10 @@ bool DocStringAnalyser::visit(ContractDefinition const& _contract)
 
 bool DocStringAnalyser::visit(FunctionDefinition const& _function)
 {
-	handleCallable(_function, _function, _function.annotation());
+	if (_function.isConstructor())
+		handleConstructor(_function, _function, _function.annotation());
+	else
+		handleCallable(_function, _function, _function.annotation());
 	return true;
 }
 
@@ -66,15 +69,11 @@ bool DocStringAnalyser::visit(EventDefinition const& _event)
 	return true;
 }
 
-void DocStringAnalyser::handleCallable(
+void DocStringAnalyser::checkParameters(
 	CallableDeclaration const& _callable,
-	Documented const& _node,
 	DocumentedAnnotation& _annotation
 )
 {
-	static const set<string> validTags = set<string>{"author", "dev", "notice", "return", "param"};
-	parseDocStrings(_node, _annotation, validTags, "functions");
-
 	set<string> validParams;
 	for (auto const& p: _callable.parameters())
 		validParams.insert(p->name());
@@ -89,6 +88,29 @@ void DocStringAnalyser::handleCallable(
 				i->second.paramName +
 				"\" not found in the parameter list of the function."
 			);
+
+}
+
+void DocStringAnalyser::handleConstructor(
+	CallableDeclaration const& _callable,
+	Documented const& _node,
+	DocumentedAnnotation& _annotation
+)
+{
+	static const set<string> validTags = set<string>{"author", "dev", "notice", "param"};
+	parseDocStrings(_node, _annotation, validTags, "constructor");
+	checkParameters(_callable, _annotation);
+}
+
+void DocStringAnalyser::handleCallable(
+	CallableDeclaration const& _callable,
+	Documented const& _node,
+	DocumentedAnnotation& _annotation
+)
+{
+	static const set<string> validTags = set<string>{"author", "dev", "notice", "return", "param"};
+	parseDocStrings(_node, _annotation, validTags, "functions");
+	checkParameters(_callable, _annotation);
 }
 
 void DocStringAnalyser::parseDocStrings(

libsolidity/analysis/DocStringAnalyser.h

@@ -48,6 +48,17 @@ private:
 	virtual bool visit(ModifierDefinition const& _modifier) override;
 	virtual bool visit(EventDefinition const& _event) override;
 
+	void checkParameters(
+		CallableDeclaration const& _callable,
+		DocumentedAnnotation& _annotation
+	);
+
+	void handleConstructor(
+		CallableDeclaration const& _callable,
+		Documented const& _node,
+		DocumentedAnnotation& _annotation
+	);
+
 	void handleCallable(
 		CallableDeclaration const& _callable,
 		Documented const& _node,

libsolidity/analysis/NameAndTypeResolver.cpp

@@ -626,6 +626,17 @@ void DeclarationRegistrationHelper::endVisit(ModifierDefinition&)
 	closeCurrentScope();
 }
 
+bool DeclarationRegistrationHelper::visit(FunctionTypeName& _funTypeName)
+{
+	enterNewSubScope(_funTypeName);
+	return true;
+}
+
+void DeclarationRegistrationHelper::endVisit(FunctionTypeName&)
+{
+	closeCurrentScope();
+}
+
 bool DeclarationRegistrationHelper::visit(Block& _block)
 {
 	_block.setScope(m_currentScope);

libsolidity/analysis/NameAndTypeResolver.h

@@ -171,6 +171,8 @@ private:
 	void endVisit(FunctionDefinition& _function) override;
 	bool visit(ModifierDefinition& _modifier) override;
 	void endVisit(ModifierDefinition& _modifier) override;
+	bool visit(FunctionTypeName& _funTypeName) override;
+	void endVisit(FunctionTypeName& _funTypeName) override;
 	bool visit(Block& _block) override;
 	void endVisit(Block& _block) override;
 	bool visit(ForStatement& _forLoop) override;

libsolidity/analysis/ReferencesResolver.cpp

@@ -30,7 +30,10 @@
 #include <libsolidity/inlineasm/AsmData.h>
 #include <libsolidity/interface/ErrorReporter.h>
 
+#include <libdevcore/StringUtils.h>
+
 #include <boost/algorithm/string.hpp>
+#include <boost/range/adaptor/transformed.hpp>
 
 using namespace std;
 using namespace dev;
@@ -155,7 +158,10 @@ void ReferencesResolver::endVisit(UserDefinedTypeName const& _typeName)
 	else if (ContractDefinition const* contract = dynamic_cast<ContractDefinition const*>(declaration))
 		_typeName.annotation().type = make_shared<ContractType>(*contract);
 	else
+	{
+		_typeName.annotation().type = make_shared<TupleType>();
 		typeError(_typeName.location(), "Name has to refer to a struct, enum or contract.");
+	}
 }
 
 void ReferencesResolver::endVisit(FunctionTypeName const& _typeName)
@@ -166,13 +172,13 @@ void ReferencesResolver::endVisit(FunctionTypeName const& _typeName)
 	case VariableDeclaration::Visibility::External:
 		break;
 	default:
-		typeError(_typeName.location(), "Invalid visibility, can only be \"external\" or \"internal\".");
+		fatalTypeError(_typeName.location(), "Invalid visibility, can only be \"external\" or \"internal\".");
 		return;
 	}
 
 	if (_typeName.isPayable() && _typeName.visibility() != VariableDeclaration::Visibility::External)
 	{
-		typeError(_typeName.location(), "Only external function types can be payable.");
+		fatalTypeError(_typeName.location(), "Only external function types can be payable.");
 		return;
 	}
 
@@ -182,7 +188,7 @@ void ReferencesResolver::endVisit(FunctionTypeName const& _typeName)
 			solAssert(t->annotation().type, "Type not set for parameter.");
 			if (!t->annotation().type->canBeUsedExternally(false))
 			{
-				typeError(t->location(), "Internal type cannot be used for external function type.");
+				fatalTypeError(t->location(), "Internal type cannot be used for external function type.");
 				return;
 			}
 		}
@@ -300,6 +306,9 @@ void ReferencesResolver::endVisit(VariableDeclaration const& _variable)
 	if (_variable.annotation().type)
 		return;
 
+	if (_variable.isConstant() && !_variable.isStateVariable())
+		m_errorReporter.declarationError(_variable.location(), "The \"constant\" keyword can only be used for state variables.");
+
 	if (!_variable.typeName())
 	{
 		// This can still happen in very unusual cases where a developer uses constructs, such as
@@ -309,127 +318,92 @@ void ReferencesResolver::endVisit(VariableDeclaration const& _variable)
 		// after this step.
 		return;
 	}
-
-	TypePointer type;
-	type = _variable.typeName()->annotation().type;
 	using Location = VariableDeclaration::Location;
 	Location varLoc = _variable.referenceLocation();
 	DataLocation typeLoc = DataLocation::Memory;
-	// References are forced to calldata for external function parameters (not return)
-	// and memory for parameters (also return) of publicly visible functions.
-	// They default to memory for function parameters and storage for local variables.
-	// As an exception, "storage" is allowed for library functions.
-	if (auto ref = dynamic_cast<ReferenceType const*>(type.get()))
+
+	set<Location> allowedDataLocations = _variable.allowedDataLocations();
+	if (!allowedDataLocations.count(varLoc))
 	{
-		bool isPointer = true;
-		if (_variable.isExternalCallableParameter())
+		auto locationToString = [](VariableDeclaration::Location _location) -> string
 		{
-			auto const& contract = dynamic_cast<ContractDefinition const&>(
-				*dynamic_cast<Declaration const&>(*_variable.scope()).scope()
-			);
-			if (contract.isLibrary())
+			switch (_location)
 			{
-				if (varLoc == Location::Memory)
-					fatalTypeError(_variable.location(),
-						"Location has to be calldata or storage for external "
-						"library functions (remove the \"memory\" keyword)."
-					);
+			case Location::Memory: return "\"memory\"";
+			case Location::Storage: return "\"storage\"";
+			case Location::CallData: return "\"calldata\"";
+			case Location::Default: return "none";
 			}
-			else
-			{
-				// force location of external function parameters (not return) to calldata
-				if (varLoc != Location::CallData && varLoc != Location::Default)
-					fatalTypeError(_variable.location(),
-						"Location has to be calldata for external functions "
-						"(remove the \"memory\" or \"storage\" keyword)."
-					);
-			}
-			if (varLoc == Location::Default || varLoc == Location::CallData)
-				typeLoc = DataLocation::CallData;
-			else
-				typeLoc = varLoc == Location::Memory ? DataLocation::Memory : DataLocation::Storage;
-		}
-		else if (_variable.isCallableParameter() && dynamic_cast<Declaration const&>(*_variable.scope()).isPublic())
-		{
-			auto const& contract = dynamic_cast<ContractDefinition const&>(
-				*dynamic_cast<Declaration const&>(*_variable.scope()).scope()
-			);
-			// force locations of public or external function (return) parameters to memory
-			if (varLoc != Location::Memory && varLoc != Location::Default && !contract.isLibrary())
-				fatalTypeError(_variable.location(),
-					"Location has to be memory for publicly visible functions "
-					"(remove the \"storage\" or \"calldata\" keyword)."
-				);
-			if (varLoc == Location::Default || !contract.isLibrary())
-				typeLoc = DataLocation::Memory;
-			else
-			{
-				if (varLoc == Location::CallData)
-					fatalTypeError(_variable.location(),
-						"Location cannot be calldata for non-external functions "
-						"(remove the \"calldata\" keyword)."
-					);
-				typeLoc = varLoc == Location::Memory ? DataLocation::Memory : DataLocation::Storage;
-			}
-		}
+			return {};
+		};
+
+		string errorString;
+		if (!_variable.hasReferenceOrMappingType())
+			errorString = "Data location can only be specified for array, struct or mapping types";
 		else
 		{
-			if (_variable.isConstant())
-			{
-				if (varLoc != Location::Default && varLoc != Location::Memory)
-					fatalTypeError(
-						_variable.location(),
-						"Data location has to be \"memory\" (or unspecified) for constants."
-					);
-				typeLoc = DataLocation::Memory;
-			}
-			else if (varLoc == Location::Default)
-			{
-				if (_variable.isCallableParameter())
-					typeLoc = DataLocation::Memory;
-				else
-				{
-					typeLoc = DataLocation::Storage;
-					if (_variable.isLocalVariable())
-						typeError(
-							_variable.location(),
-							"Data location must be specified as either \"memory\" or \"storage\"."
-						);
-				}
-			}
+			errorString = "Data location must be " +
+			joinHumanReadable(
+				allowedDataLocations | boost::adaptors::transformed(locationToString),
+				", ",
+				" or "
+			);
+			if (_variable.isCallableParameter())
+				errorString +=
+					" for " +
+					string(_variable.isReturnParameter() ? "return " : "") +
+					"parameter in" +
+					string(_variable.isExternalCallableParameter() ? " external" : "") +
+					" function";
 			else
-			{
-				switch (varLoc)
-				{
-				case Location::Memory:
-					typeLoc = DataLocation::Memory;
-					break;
-				case Location::Storage:
-					typeLoc = DataLocation::Storage;
-					break;
-				case Location::CallData:
-					fatalTypeError(_variable.location(),
-						"Variable cannot be declared as \"calldata\" (remove the \"calldata\" keyword)."
-					);
-					break;
-				default:
-					solAssert(false, "Unknown data location");
-				}
-			}
-			isPointer = !_variable.isStateVariable();
+				errorString += " for variable";
 		}
+		errorString += ", but " + locationToString(varLoc) + " was given.";
+		typeError(_variable.location(), errorString);
+
+		solAssert(!allowedDataLocations.empty(), "");
+		varLoc = *allowedDataLocations.begin();
+	}
+
+	// Find correct data location.
+	if (_variable.isEventParameter())
+	{
+		solAssert(varLoc == Location::Default, "");
+		typeLoc = DataLocation::Memory;
+	}
+	else if (_variable.isStateVariable())
+	{
+		solAssert(varLoc == Location::Default, "");
+		typeLoc = _variable.isConstant() ? DataLocation::Memory : DataLocation::Storage;
+	}
+	else if (
+		dynamic_cast<StructDefinition const*>(_variable.scope()) ||
+		dynamic_cast<EnumDefinition const*>(_variable.scope())
+	)
+		// The actual location will later be changed depending on how the type is used.
+		typeLoc = DataLocation::Storage;
+	else
+		switch (varLoc)
+		{
+		case Location::Memory:
+			typeLoc = DataLocation::Memory;
+			break;
+		case Location::Storage:
+			typeLoc = DataLocation::Storage;
+			break;
+		case Location::CallData:
+			typeLoc = DataLocation::CallData;
+			break;
+		case Location::Default:
+			solAssert(!_variable.hasReferenceOrMappingType(), "Data location not properly set.");
+		}
+
+	TypePointer type = _variable.typeName()->annotation().type;
+	if (auto ref = dynamic_cast<ReferenceType const*>(type.get()))
+	{
+		bool isPointer = !_variable.isStateVariable();
 		type = ref->copyForLocation(typeLoc, isPointer);
 	}
-	else if (dynamic_cast<MappingType const*>(type.get()))
-	{
-		if (_variable.isLocalVariable() && varLoc != Location::Storage)
-			typeError(
-				_variable.location(),
-				"Data location for mappings must be specified as \"storage\"."
-			);
-	}
-	else if (varLoc != Location::Default && !ref)
-		typeError(_variable.location(), "Data location can only be given for array or struct types.");
 
 	_variable.annotation().type = type;
 }

libsolidity/analysis/TypeChecker.cpp

@@ -525,6 +525,75 @@ void TypeChecker::checkDoubleStorageAssignment(Assignment const& _assignment)
 		);
 }
 
+TypePointer TypeChecker::typeCheckABIDecodeAndRetrieveReturnType(FunctionCall const& _functionCall, bool _abiEncoderV2)
+{
+	vector<ASTPointer<Expression const>> arguments = _functionCall.arguments();
+	if (arguments.size() != 2)
+		m_errorReporter.typeError(
+			_functionCall.location(),
+			"This function takes two arguments, but " +
+			toString(arguments.size()) +
+			" were provided."
+		);
+	if (arguments.size() >= 1 && !type(*arguments.front())->isImplicitlyConvertibleTo(ArrayType(DataLocation::Memory)))
+		m_errorReporter.typeError(
+			arguments.front()->location(),
+			"Invalid type for argument in function call. "
+			"Invalid implicit conversion from " +
+			type(*arguments.front())->toString() +
+			" to bytes memory requested."
+		);
+
+	TypePointer returnType = make_shared<TupleType>();
+
+	if (arguments.size() < 2)
+		return returnType;
+
+	// The following is a rather syntactic restriction, but we check it here anyway:
+	// The second argument has to be a tuple expression containing type names.
+	TupleExpression const* tupleExpression = dynamic_cast<TupleExpression const*>(arguments[1].get());
+	if (!tupleExpression)
+	{
+		m_errorReporter.typeError(
+			arguments[1]->location(),
+			"The second argument to \"abi.decode\" has to be a tuple of types."
+		);
+		return returnType;
+	}
+
+	vector<TypePointer> components;
+	for (auto const& typeArgument: tupleExpression->components())
+	{
+		solAssert(typeArgument, "");
+		if (TypeType const* argTypeType = dynamic_cast<TypeType const*>(type(*typeArgument).get()))
+		{
+			TypePointer actualType = argTypeType->actualType();
+			solAssert(actualType, "");
+			// We force memory because the parser currently cannot handle
+			// data locations. Furthermore, storage can be a little dangerous and
+			// calldata is not really implemented anyway.
+			actualType = ReferenceType::copyForLocationIfReference(DataLocation::Memory, actualType);
+			solAssert(
+				!actualType->dataStoredIn(DataLocation::CallData) &&
+				!actualType->dataStoredIn(DataLocation::Storage),
+				""
+			);
+			if (!actualType->fullEncodingType(false, _abiEncoderV2, false))
+				m_errorReporter.typeError(
+					typeArgument->location(),
+					"Decoding type " + actualType->toString(false)  + " not supported."
+				);
+			components.push_back(actualType);
+		}
+		else
+		{
+			m_errorReporter.typeError(typeArgument->location(), "Argument has to be a type name.");
+			components.push_back(make_shared<TupleType>());
+		}
+	}
+	return make_shared<TupleType>(components);
+}
+
 void TypeChecker::endVisit(InheritanceSpecifier const& _inheritance)
 {
 	auto base = dynamic_cast<ContractDefinition const*>(&dereference(_inheritance.name()));
@@ -580,9 +649,6 @@ void TypeChecker::endVisit(UsingForDirective const& _usingFor)
 
 bool TypeChecker::visit(StructDefinition const& _struct)
 {
-	if (m_scope->contractKind() == ContractDefinition::ContractKind::Interface)
-		m_errorReporter.typeError(_struct.location(), "Structs cannot be defined in interfaces.");
-
 	for (ASTPointer<VariableDeclaration> const& member: _struct.members())
 		if (!type(*member)->canBeStored())
 			m_errorReporter.typeError(member->location(), "Type cannot be used in struct.");
@@ -610,7 +676,10 @@ bool TypeChecker::visit(StructDefinition const& _struct)
 	if (CycleDetector<StructDefinition>(visitor).run(_struct) != nullptr)
 		m_errorReporter.fatalTypeError(_struct.location(), "Recursive struct definition.");
 
+	bool insideStruct = true;
+	swap(insideStruct, m_insideStruct);
 	ASTNode::listAccept(_struct.members(), *this);
+	m_insideStruct = insideStruct;
 
 	return false;
 }
@@ -629,7 +698,15 @@ bool TypeChecker::visit(FunctionDefinition const& _function)
 	}
 	for (ASTPointer<VariableDeclaration> const& var: _function.parameters() + _function.returnParameters())
 	{
-		if (!type(*var)->canLiveOutsideStorage())
+		if (
+			type(*var)->category() == Type::Category::Mapping &&
+			!type(*var)->dataStoredIn(DataLocation::Storage)
+		)
+			m_errorReporter.typeError(var->location(), "Mapping types can only have a data location of \"storage\".");
+		else if (
+			!type(*var)->canLiveOutsideStorage() &&
+			_function.visibility() > FunctionDefinition::Visibility::Internal
+		)
 			m_errorReporter.typeError(var->location(), "Type is required to live outside storage.");
 		if (_function.visibility() >= FunctionDefinition::Visibility::Public && !(type(*var)->interfaceType(isLibraryFunction)))
 			m_errorReporter.fatalTypeError(var->location(), "Internal or recursive type is not allowed for public or external functions.");
@@ -690,10 +767,12 @@ bool TypeChecker::visit(FunctionDefinition const& _function)
 bool TypeChecker::visit(VariableDeclaration const& _variable)
 {
 	// Forbid any variable declarations inside interfaces unless they are part of
-	// a function's input/output parameters.
+	// * a function's input/output parameters,
+	// * or inside of a struct definition.
 	if (
 		m_scope->contractKind() == ContractDefinition::ContractKind::Interface
 		&& !_variable.isCallableParameter()
+		&& !m_insideStruct
 	)
 		m_errorReporter.typeError(_variable.location(), "Variables cannot be declared in interfaces.");
 
@@ -711,8 +790,6 @@ bool TypeChecker::visit(VariableDeclaration const& _variable)
 		expectType(*_variable.value(), *varType);
 	if (_variable.isConstant())
 	{
-		if (!_variable.isStateVariable())
-			m_errorReporter.typeError(_variable.location(), "Illegal use of \"constant\" specifier.");
 		if (!_variable.type()->isValueType())
 		{
 			bool allowed = false;
@@ -742,7 +819,9 @@ bool TypeChecker::visit(VariableDeclaration const& _variable)
 	)
 		m_errorReporter.typeError(_variable.location(), "Internal or recursive type is not allowed for public state variables.");
 
-	if (varType->category() == Type::Category::Array)
+	switch (varType->category())
+	{
+	case Type::Category::Array:
 		if (auto arrayType = dynamic_cast<ArrayType const*>(varType.get()))
 			if (
 				((arrayType->location() == DataLocation::Memory) ||
@@ -750,6 +829,18 @@ bool TypeChecker::visit(VariableDeclaration const& _variable)
 				!arrayType->validForCalldata()
 			)
 				m_errorReporter.typeError(_variable.location(), "Array is too large to be encoded.");
+		break;
+	case Type::Category::Mapping:
+		if (auto mappingType = dynamic_cast<MappingType const*>(varType.get()))
+			if (
+				mappingType->keyType()->isDynamicallySized() &&
+				_variable.visibility() == Declaration::Visibility::Public
+			)
+				m_errorReporter.typeError(_variable.location(), "Dynamically-sized keys for public mappings are not supported.");
+		break;
+	default:
+		break;
+	}
 
 	return false;
 }
@@ -818,7 +909,17 @@ bool TypeChecker::visit(EventDefinition const& _eventDef)
 	for (ASTPointer<VariableDeclaration> const& var: _eventDef.parameters())
 	{
 		if (var->isIndexed())
+		{
 			numIndexed++;
+			if (
+				_eventDef.sourceUnit().annotation().experimentalFeatures.count(ExperimentalFeature::ABIEncoderV2) &&
+				dynamic_cast<ReferenceType const*>(type(*var).get())
+			)
+				m_errorReporter.typeError(
+					var->location(),
+					"Indexed reference types cannot yet be used with ABIEncoderV2."
+				);
+		}
 		if (!type(*var)->canLiveOutsideStorage())
 			m_errorReporter.typeError(var->location(), "Type is required to live outside storage.");
 		if (!type(*var)->interfaceType(false))
@@ -1282,7 +1383,8 @@ void TypeChecker::endVisit(ExpressionStatement const& _statement)
 			if (
 				kind == FunctionType::Kind::BareCall ||
 				kind == FunctionType::Kind::BareCallCode ||
-				kind == FunctionType::Kind::BareDelegateCall
+				kind == FunctionType::Kind::BareDelegateCall ||
+				kind == FunctionType::Kind::BareStaticCall
 			)
 				m_errorReporter.warning(_statement.location(), "Return value of low-level calls not used.");
 			else if (kind == FunctionType::Kind::Send)
@@ -1626,10 +1728,13 @@ bool TypeChecker::visit(FunctionCall const& _functionCall)
 		else
 		{
 			TypePointer const& argType = type(*arguments.front());
+			// Resulting data location is memory unless we are converting from a reference
+			// type with a different data location.
+			// (data location cannot yet be specified for type conversions)
+			DataLocation dataLoc = DataLocation::Memory;
 			if (auto argRefType = dynamic_cast<ReferenceType const*>(argType.get()))
-				// do not change the data location when converting
-				// (data location cannot yet be specified for type conversions)
-				resultType = ReferenceType::copyForLocationIfReference(argRefType->location(), resultType);
+				dataLoc = argRefType->location();
+			resultType = ReferenceType::copyForLocationIfReference(dataLoc, resultType);
 			if (!argType->isExplicitlyConvertibleTo(*resultType))
 				m_errorReporter.typeError(
 					_functionCall.location(),
@@ -1674,6 +1779,9 @@ bool TypeChecker::visit(FunctionCall const& _functionCall)
 		return false;
 	}
 
+	if (functionType->kind() == FunctionType::Kind::BareStaticCall && !m_evmVersion.hasStaticCall())
+		m_errorReporter.typeError(_functionCall.location(), "\"staticcall\" is not supported by the VM version.");
+
 	auto returnTypes =
 		allowDynamicTypes ?
 		functionType->returnParameterTypes() :
@@ -1716,7 +1824,11 @@ bool TypeChecker::visit(FunctionCall const& _functionCall)
 		}
 	}
 
-	if (functionType->takesArbitraryParameters() && arguments.size() < parameterTypes.size())
+	bool const abiEncoderV2 = m_scope->sourceUnit().annotation().experimentalFeatures.count(ExperimentalFeature::ABIEncoderV2);
+
+	if (functionType->kind() == FunctionType::Kind::ABIDecode)
+		_functionCall.annotation().type = typeCheckABIDecodeAndRetrieveReturnType(_functionCall, abiEncoderV2);
+	else if (functionType->takesArbitraryParameters() && arguments.size() < parameterTypes.size())
 	{
 		solAssert(_functionCall.annotation().kind == FunctionCallKind::FunctionCall, "");
 		m_errorReporter.typeError(
@@ -1750,7 +1862,8 @@ bool TypeChecker::visit(FunctionCall const& _functionCall)
 		else if (
 			functionType->kind() == FunctionType::Kind::BareCall ||
 			functionType->kind() == FunctionType::Kind::BareCallCode ||
-			functionType->kind() == FunctionType::Kind::BareDelegateCall
+			functionType->kind() == FunctionType::Kind::BareDelegateCall ||
+			functionType->kind() == FunctionType::Kind::BareStaticCall
 		)
 		{
 			if (arguments.empty())
@@ -1771,8 +1884,6 @@ bool TypeChecker::visit(FunctionCall const& _functionCall)
 	}
 	else if (isPositionalCall)
 	{
-		bool const abiEncodeV2 = m_scope->sourceUnit().annotation().experimentalFeatures.count(ExperimentalFeature::ABIEncoderV2);
-
 		for (size_t i = 0; i < arguments.size(); ++i)
 		{
 			auto const& argType = type(*arguments[i]);
@@ -1785,7 +1896,7 @@ bool TypeChecker::visit(FunctionCall const& _functionCall)
 						m_errorReporter.typeError(arguments[i]->location(), "Invalid rational number (too large or division by zero).");
 						errored = true;
 					}
-				if (!errored && !argType->fullEncodingType(false, abiEncodeV2, !functionType->padArguments()))
+				if (!errored && !argType->fullEncodingType(false, abiEncoderV2, !functionType->padArguments()))
 					m_errorReporter.typeError(arguments[i]->location(), "This type cannot be encoded.");
 			}
 			else if (!type(*arguments[i])->isImplicitlyConvertibleTo(*parameterTypes[i]))
@@ -1800,7 +1911,8 @@ bool TypeChecker::visit(FunctionCall const& _functionCall)
 				if (
 					functionType->kind() == FunctionType::Kind::BareCall ||
 					functionType->kind() == FunctionType::Kind::BareCallCode ||
-					functionType->kind() == FunctionType::Kind::BareDelegateCall
+					functionType->kind() == FunctionType::Kind::BareDelegateCall ||
+					functionType->kind() == FunctionType::Kind::BareStaticCall
 				)
 					msg += " This function requires a single bytes argument. If all your arguments are value types, you can use abi.encode(...) to properly generate it.";
 				else if (
@@ -2348,22 +2460,6 @@ void TypeChecker::expectType(Expression const& _expression, Type const& _expecte
 				"."
 			);
 	}
-
-	if (
-		type(_expression)->category() == Type::Category::RationalNumber &&
-		_expectedType.category() == Type::Category::FixedBytes
-	)
-	{
-		auto literal = dynamic_cast<Literal const*>(&_expression);
-
-		if (literal && !literal->isHexNumber())
-			m_errorReporter.warning(
-				_expression.location(),
-				"Decimal literal assigned to bytesXX variable will be left-aligned. "
-				"Use an explicit conversion to silence this warning."
-			);
-	}
-
 }
 
 void TypeChecker::requireLValue(Expression const& _expression)

libsolidity/analysis/TypeChecker.h

@@ -91,6 +91,11 @@ private:
 	// and reports an error, if not.
 	void checkExpressionAssignment(Type const& _type, Expression const& _expression);
 
+	/// Performs type checks for ``abi.decode(bytes memory, (...))`` and returns the
+	/// return type (which is basically the second argument) if successful. It returns
+	/// the empty tuple type or error.
+	TypePointer typeCheckABIDecodeAndRetrieveReturnType(FunctionCall const& _functionCall, bool _abiEncoderV2);
+
 	virtual void endVisit(InheritanceSpecifier const& _inheritance) override;
 	virtual void endVisit(UsingForDirective const& _usingFor) override;
 	virtual bool visit(StructDefinition const& _struct) override;
@@ -149,6 +154,9 @@ private:
 	/// Flag indicating whether we are currently inside an EmitStatement.
 	bool m_insideEmitStatement = false;
 
+	/// Flag indicating whether we are currently inside a StructDefinition.
+	bool m_insideStruct = false;
+
 	ErrorReporter& m_errorReporter;
 };
 

libsolidity/analysis/ViewPureChecker.cpp

@@ -295,7 +295,7 @@ void ViewPureChecker::endVisit(MemberAccess const& _memberAccess)
 	{
 		// we can ignore the kind of magic and only look at the name of the member
 		set<string> static const pureMembers{
-			"encode", "encodePacked", "encodeWithSelector", "encodeWithSignature", "data", "sig", "blockhash"
+			"encode", "encodePacked", "encodeWithSelector", "encodeWithSignature", "decode", "data", "sig", "blockhash"
 		};
 		if (!pureMembers.count(member))
 			mutability = StateMutability::View;

libsolidity/ast/AST.cpp

@@ -397,7 +397,7 @@ SourceUnit const& Scopable::sourceUnit() const
 {
 	ASTNode const* s = scope();
 	solAssert(s, "");
-	// will not always be a declaratoion
+	// will not always be a declaration
 	while (dynamic_cast<Scopable const*>(s) && dynamic_cast<Scopable const*>(s)->scope())
 		s = dynamic_cast<Scopable const*>(s)->scope();
 	return dynamic_cast<SourceUnit const&>(*s);
@@ -418,6 +418,7 @@ bool VariableDeclaration::isLocalVariable() const
 {
 	auto s = scope();
 	return
+		dynamic_cast<FunctionTypeName const*>(s) ||
 		dynamic_cast<CallableDeclaration const*>(s) ||
 		dynamic_cast<Block const*>(s) ||
 		dynamic_cast<ForStatement const*>(s);
@@ -425,14 +426,18 @@ bool VariableDeclaration::isLocalVariable() const
 
 bool VariableDeclaration::isCallableParameter() const
 {
-	auto const* callable = dynamic_cast<CallableDeclaration const*>(scope());
-	if (!callable)
-		return false;
-	for (auto const& variable: callable->parameters())
-		if (variable.get() == this)
-			return true;
-	if (callable->returnParameterList())
-		for (auto const& variable: callable->returnParameterList()->parameters())
+	if (isReturnParameter())
+		return true;
+
+	vector<ASTPointer<VariableDeclaration>> const* parameters = nullptr;
+
+	if (auto const* funTypeName = dynamic_cast<FunctionTypeName const*>(scope()))
+		parameters = &funTypeName->parameterTypes();
+	else if (auto const* callable = dynamic_cast<CallableDeclaration const*>(scope()))
+		parameters = &callable->parameters();
+
+	if (parameters)
+		for (auto const& variable: *parameters)
 			if (variable.get() == this)
 				return true;
 	return false;
@@ -445,11 +450,16 @@ bool VariableDeclaration::isLocalOrReturn() const
 
 bool VariableDeclaration::isReturnParameter() const
 {
-	auto const* callable = dynamic_cast<CallableDeclaration const*>(scope());
-	if (!callable)
-		return false;
-	if (callable->returnParameterList())
-		for (auto const& variable: callable->returnParameterList()->parameters())
+	vector<ASTPointer<VariableDeclaration>> const* returnParameters = nullptr;
+
+	if (auto const* funTypeName = dynamic_cast<FunctionTypeName const*>(scope()))
+		returnParameters = &funTypeName->returnParameterTypes();
+	else if (auto const* callable = dynamic_cast<CallableDeclaration const*>(scope()))
+		if (callable->returnParameterList())
+			returnParameters = &callable->returnParameterList()->parameters();
+
+	if (returnParameters)
+		for (auto const& variable: *returnParameters)
 			if (variable.get() == this)
 				return true;
 	return false;
@@ -457,15 +467,88 @@ bool VariableDeclaration::isReturnParameter() const
 
 bool VariableDeclaration::isExternalCallableParameter() const
 {
-	auto const* callable = dynamic_cast<CallableDeclaration const*>(scope());
-	if (!callable || callable->visibility() != Declaration::Visibility::External)
+	if (!isCallableParameter())
 		return false;
-	for (auto const& variable: callable->parameters())
-		if (variable.get() == this)
-			return true;
+
+	if (auto const* callable = dynamic_cast<CallableDeclaration const*>(scope()))
+		if (callable->visibility() == Declaration::Visibility::External)
+			return !isReturnParameter();
+
 	return false;
 }
 
+bool VariableDeclaration::isInternalCallableParameter() const
+{
+	if (!isCallableParameter())
+		return false;
+
+	if (auto const* funTypeName = dynamic_cast<FunctionTypeName const*>(scope()))
+		return funTypeName->visibility() == Declaration::Visibility::Internal;
+	else if (auto const* callable = dynamic_cast<CallableDeclaration const*>(scope()))
+		return callable->visibility() <= Declaration::Visibility::Internal;
+	return false;
+}
+
+bool VariableDeclaration::isLibraryFunctionParameter() const
+{
+	if (!isCallableParameter())
+		return false;
+	if (auto const* funDef = dynamic_cast<FunctionDefinition const*>(scope()))
+		return dynamic_cast<ContractDefinition const&>(*funDef->scope()).isLibrary();
+	else
+		return false;
+}
+
+bool VariableDeclaration::isEventParameter() const
+{
+	return dynamic_cast<EventDefinition const*>(scope()) != nullptr;
+}
+
+bool VariableDeclaration::hasReferenceOrMappingType() const
+{
+	solAssert(typeName(), "");
+	solAssert(typeName()->annotation().type, "Can only be called after reference resolution");
+	TypePointer const& type = typeName()->annotation().type;
+	return type->category() == Type::Category::Mapping || dynamic_cast<ReferenceType const*>(type.get());
+}
+
+set<VariableDeclaration::Location> VariableDeclaration::allowedDataLocations() const
+{
+	using Location = VariableDeclaration::Location;
+
+	if (!hasReferenceOrMappingType() || isStateVariable() || isEventParameter())
+		return set<Location>{ Location::Default };
+	else if (isStateVariable() && isConstant())
+		return set<Location>{ Location::Memory };
+	else if (isExternalCallableParameter())
+	{
+		set<Location> locations{ Location::CallData };
+		if (isLibraryFunctionParameter())
+			locations.insert(Location::Storage);
+		return locations;
+	}
+	else if (isCallableParameter())
+	{
+		set<Location> locations{ Location::Memory };
+		if (isInternalCallableParameter() || isLibraryFunctionParameter())
+			locations.insert(Location::Storage);
+		return locations;
+	}
+	else if (isLocalVariable())
+	{
+		solAssert(typeName(), "");
+		solAssert(typeName()->annotation().type, "Can only be called after reference resolution");
+		if (typeName()->annotation().type->category() == Type::Category::Mapping)
+			return set<Location>{ Location::Storage };
+		else
+			//  TODO: add Location::Calldata once implemented for local variables.
+			return set<Location>{ Location::Memory, Location::Storage };
+	}
+	else
+		// Struct members etc.
+		return set<Location>{ Location::Default };
+}
+
 TypePointer VariableDeclaration::type() const
 {
 	return annotation().type;
@@ -580,7 +663,7 @@ bool Literal::passesAddressChecksum() const
 	return dev::passesAddressChecksum(value(), true);
 }
 
-std::string Literal::getChecksummedAddress() const
+string Literal::getChecksummedAddress() const
 {
 	solAssert(isHexNumber(), "Expected hex number");
 	/// Pad literal to be a proper hex address.

libsolidity/ast/AST.h

@@ -685,6 +685,8 @@ public:
 	virtual bool isLValue() const override;
 	virtual bool isPartOfExternalInterface() const override { return isPublic(); }
 
+	/// @returns true iff this variable is the parameter (or return parameter) of a function
+	/// (or function type name or event) or declared inside a function body.
 	bool isLocalVariable() const;
 	/// @returns true if this variable is a parameter or return parameter of a function.
 	bool isCallableParameter() const;
@@ -693,13 +695,27 @@ public:
 	/// @returns true if this variable is a local variable or return parameter.
 	bool isLocalOrReturn() const;
 	/// @returns true if this variable is a parameter (not return parameter) of an external function.
+	/// This excludes parameters of external function type names.
 	bool isExternalCallableParameter() const;
+	/// @returns true if this variable is a parameter or return parameter of an internal function
+	/// or a function type of internal visibility.
+	bool isInternalCallableParameter() const;
+	/// @returns true iff this variable is a parameter(or return parameter of a library function
+	bool isLibraryFunctionParameter() const;
 	/// @returns true if the type of the variable does not need to be specified, i.e. it is declared
 	/// in the body of a function or modifier.
+	/// @returns true if this variable is a parameter of an event.
+	bool isEventParameter() const;
+	/// @returns true if the type of the variable is a reference or mapping type, i.e.
+	/// array, struct or mapping. These types can take a data location (and often require it).
+	/// Can only be called after reference resolution.
+	bool hasReferenceOrMappingType() const;
 	bool isStateVariable() const { return m_isStateVariable; }
 	bool isIndexed() const { return m_isIndexed; }
 	bool isConstant() const { return m_isConstant; }
 	Location referenceLocation() const { return m_location; }
+	/// @returns a set of allowed storage locations for the variable.
+	std::set<Location> allowedDataLocations() const;
 
 	virtual TypePointer type() const override;
 

libsolidity/ast/Types.cpp

@@ -355,13 +355,7 @@ TypePointer Type::forLiteral(Literal const& _literal)
 	case Token::FalseLiteral:
 		return make_shared<BoolType>();
 	case Token::Number:
-	{
-		tuple<bool, rational> validLiteral = RationalNumberType::isValidLiteral(_literal);
-		if (get<0>(validLiteral) == true)
-			return make_shared<RationalNumberType>(get<1>(validLiteral));
-		else
-			return TypePointer();
-	}
+		return RationalNumberType::forLiteral(_literal);
 	case Token::StringLiteral:
 		return make_shared<StringLiteralType>(_literal);
 	default:
@@ -400,17 +394,17 @@ TypePointer Type::fullEncodingType(bool _inLibraryCall, bool _encoderV2, bool _p
 		encodingType = encodingType->interfaceType(_inLibraryCall);
 	if (encodingType)
 		encodingType = encodingType->encodingType();
-	if (auto structType = dynamic_cast<StructType const*>(encodingType.get()))
-	{
-		// Structs are fine in the following circumstances:
-		// - ABIv2 without packed encoding or,
-		// - storage struct for a library
-		if (!(
-			(_encoderV2 && !_packed) ||
-			(structType->location() == DataLocation::Storage && _inLibraryCall)
-		))
+	// Structs are fine in the following circumstances:
+	// - ABIv2 without packed encoding or,
+	// - storage struct for a library
+	if (_inLibraryCall && encodingType->dataStoredIn(DataLocation::Storage))
+		return encodingType;
+	TypePointer baseType = encodingType;
+	while (auto const* arrayType = dynamic_cast<ArrayType const*>(baseType.get()))
+		baseType = arrayType->baseType();
+	if (dynamic_cast<StructType const*>(baseType.get()))
+		if (!_encoderV2 || _packed)
 			return TypePointer();
-	}
 	return encodingType;
 }
 
@@ -627,6 +621,7 @@ MemberList::MemberMap IntegerType::nativeMembers(ContractDefinition const*) cons
 			{"callcode", make_shared<FunctionType>(strings{"bytes memory"}, strings{"bool"}, FunctionType::Kind::BareCallCode, false, StateMutability::Payable)},
 			{"delegatecall", make_shared<FunctionType>(strings{"bytes memory"}, strings{"bool"}, FunctionType::Kind::BareDelegateCall, false)},
 			{"send", make_shared<FunctionType>(strings{"uint"}, strings{"bool"}, FunctionType::Kind::Send)},
+			{"staticcall", make_shared<FunctionType>(strings{"bytes memory"}, strings{"bool"}, FunctionType::Kind::BareStaticCall, false, StateMutability::View)},
 			{"transfer", make_shared<FunctionType>(strings{"uint"}, strings(), FunctionType::Kind::Transfer)}
 		};
 	else
@@ -779,6 +774,30 @@ tuple<bool, rational> RationalNumberType::parseRational(string const& _value)
 	}
 }
 
+TypePointer RationalNumberType::forLiteral(Literal const& _literal)
+{
+	solAssert(_literal.token() == Token::Number, "");
+	tuple<bool, rational> validLiteral = isValidLiteral(_literal);
+	if (get<0>(validLiteral))
+	{
+		TypePointer compatibleBytesType;
+		if (_literal.isHexNumber())
+		{
+			size_t digitCount = count_if(
+				_literal.value().begin() + 2, // skip "0x"
+				_literal.value().end(),
+				[](unsigned char _c) -> bool { return isxdigit(_c); }
+			);
+			// require even number of digits
+			if (!(digitCount & 1))
+				compatibleBytesType = make_shared<FixedBytesType>(digitCount / 2);
+		}
+
+		return make_shared<RationalNumberType>(get<1>(validLiteral), compatibleBytesType);
+	}
+	return TypePointer();
+}
+
 tuple<bool, rational> RationalNumberType::isValidLiteral(Literal const& _literal)
 {
 	rational value;
@@ -918,14 +937,7 @@ bool RationalNumberType::isImplicitlyConvertibleTo(Type const& _convertTo) const
 		return false;
 	}
 	case Category::FixedBytes:
-	{
-		FixedBytesType const& fixedBytes = dynamic_cast<FixedBytesType const&>(_convertTo);
-		if (isFractional())
-			return false;
-		if (integerType())
-			return fixedBytes.numBytes() * 8 >= integerType()->numBits();
-		return false;
-	}
+		return (m_value == rational(0)) || (m_compatibleBytesType && *m_compatibleBytesType == _convertTo);
 	default:
 		return false;
 	}
@@ -933,11 +945,15 @@ bool RationalNumberType::isImplicitlyConvertibleTo(Type const& _convertTo) const
 
 bool RationalNumberType::isExplicitlyConvertibleTo(Type const& _convertTo) const
 {
-	TypePointer mobType = mobileType();
-	return
-		(mobType && mobType->isExplicitlyConvertibleTo(_convertTo)) ||
-		(!isFractional() && _convertTo.category() == Category::FixedBytes)
-	;
+	if (isImplicitlyConvertibleTo(_convertTo))
+		return true;
+	else if (_convertTo.category() != Category::FixedBytes)
+	{
+		TypePointer mobType = mobileType();
+		return (mobType && mobType->isExplicitlyConvertibleTo(_convertTo));
+	}
+	else
+		return false;
 }
 
 TypePointer RationalNumberType::unaryOperatorResult(Token::Value _operator) const
@@ -1263,7 +1279,8 @@ shared_ptr<FixedPointType const> RationalNumberType::fixedPointType() const
 		return shared_ptr<FixedPointType const>();
 	// This means we round towards zero for positive and negative values.
 	bigint v = value.numerator() / value.denominator();
-	if (negative)
+
+	if (negative && v != 0)
 		// modify value to satisfy bit requirements for negative numbers:
 		// add one bit for sign and decrement because negative numbers can be larger
 		v = (v - 1) << 1;
@@ -2502,6 +2519,7 @@ string FunctionType::richIdentifier() const
 	case Kind::BareCall: id += "barecall"; break;
 	case Kind::BareCallCode: id += "barecallcode"; break;
 	case Kind::BareDelegateCall: id += "baredelegatecall"; break;
+	case Kind::BareStaticCall: id += "barestaticcall"; break;
 	case Kind::Creation: id += "creation"; break;
 	case Kind::Send: id += "send"; break;
 	case Kind::Transfer: id += "transfer"; break;
@@ -2533,6 +2551,7 @@ string FunctionType::richIdentifier() const
 	case Kind::ABIEncodePacked: id += "abiencodepacked"; break;
 	case Kind::ABIEncodeWithSelector: id += "abiencodewithselector"; break;
 	case Kind::ABIEncodeWithSignature: id += "abiencodewithsignature"; break;
+	case Kind::ABIDecode: id += "abidecode"; break;
 	}
 	id += "_" + stateMutabilityToString(m_stateMutability);
 	id += identifierList(m_parameterTypes) + "returns" + identifierList(m_returnParameterTypes);
@@ -2549,28 +2568,10 @@ bool FunctionType::operator==(Type const& _other) const
 {
 	if (_other.category() != category())
 		return false;
-
 	FunctionType const& other = dynamic_cast<FunctionType const&>(_other);
-	if (
-		m_kind != other.m_kind ||
-		m_stateMutability != other.stateMutability() ||
-		m_parameterTypes.size() != other.m_parameterTypes.size() ||
-		m_returnParameterTypes.size() != other.m_returnParameterTypes.size()
-	)
+	if (!equalExcludingStateMutability(other))
 		return false;
-
-	auto typeCompare = [](TypePointer const& _a, TypePointer const& _b) -> bool { return *_a == *_b; };
-	if (
-		!equal(m_parameterTypes.cbegin(), m_parameterTypes.cend(), other.m_parameterTypes.cbegin(), typeCompare) ||
-		!equal(m_returnParameterTypes.cbegin(), m_returnParameterTypes.cend(), other.m_returnParameterTypes.cbegin(), typeCompare)
-	)
-		return false;
-	//@todo this is ugly, but cannot be prevented right now
-	if (m_gasSet != other.m_gasSet || m_valueSet != other.m_valueSet)
-		return false;
-	if (bound() != other.bound())
-		return false;
-	if (bound() && *selfType() != *other.selfType())
+	if (m_stateMutability != other.stateMutability())
 		return false;
 	return true;
 }
@@ -2586,6 +2587,31 @@ bool FunctionType::isExplicitlyConvertibleTo(Type const& _convertTo) const
 	return _convertTo.category() == category();
 }
 
+bool FunctionType::isImplicitlyConvertibleTo(Type const& _convertTo) const
+{
+	if (_convertTo.category() != category())
+		return false;
+
+	FunctionType const& convertTo = dynamic_cast<FunctionType const&>(_convertTo);
+
+	if (!equalExcludingStateMutability(convertTo))
+		return false;
+
+	// non-payable should not be convertible to payable
+	if (m_stateMutability != StateMutability::Payable && convertTo.stateMutability() == StateMutability::Payable)
+		return false;
+
+	// payable should be convertible to non-payable, because you are free to pay 0 ether
+	if (m_stateMutability == StateMutability::Payable && convertTo.stateMutability() == StateMutability::NonPayable)
+		return true;
+
+	// e.g. pure should be convertible to view, but not the other way around.
+	if (m_stateMutability > convertTo.stateMutability())
+		return false;
+
+	return true;
+}
+
 TypePointer FunctionType::unaryOperatorResult(Token::Value _operator) const
 {
 	if (_operator == Token::Value::Delete)
@@ -2676,6 +2702,7 @@ unsigned FunctionType::sizeOnStack() const
 	case Kind::BareCall:
 	case Kind::BareCallCode:
 	case Kind::BareDelegateCall:
+	case Kind::BareStaticCall:
 	case Kind::Internal:
 	case Kind::ArrayPush:
 	case Kind::ArrayPop:
@@ -2743,6 +2770,7 @@ MemberList::MemberMap FunctionType::nativeMembers(ContractDefinition const*) con
 	case Kind::BareCall:
 	case Kind::BareCallCode:
 	case Kind::BareDelegateCall:
+	case Kind::BareStaticCall:
 	{
 		MemberList::MemberMap members;
 		if (m_kind == Kind::External)
@@ -2843,6 +2871,38 @@ bool FunctionType::hasEqualParameterTypes(FunctionType const& _other) const
 	);
 }
 
+bool FunctionType::hasEqualReturnTypes(FunctionType const& _other) const
+{
+	if (m_returnParameterTypes.size() != _other.m_returnParameterTypes.size())
+		return false;
+	return equal(
+		m_returnParameterTypes.cbegin(),
+		m_returnParameterTypes.cend(),
+		_other.m_returnParameterTypes.cbegin(),
+		[](TypePointer const& _a, TypePointer const& _b) -> bool { return *_a == *_b; }
+	);
+}
+
+bool FunctionType::equalExcludingStateMutability(FunctionType const& _other) const
+{
+	if (m_kind != _other.m_kind)
+		return false;
+
+	if (!hasEqualParameterTypes(_other) || !hasEqualReturnTypes(_other))
+		return false;
+
+	//@todo this is ugly, but cannot be prevented right now
+	if (m_gasSet != _other.m_gasSet || m_valueSet != _other.m_valueSet)
+		return false;
+
+	if (bound() != _other.bound())
+		return false;
+
+	solAssert(!bound() || *selfType() == *_other.selfType(), "");
+
+	return true;
+}
+
 bool FunctionType::isBareCall() const
 {
 	switch (m_kind)
@@ -2850,6 +2910,7 @@ bool FunctionType::isBareCall() const
 	case Kind::BareCall:
 	case Kind::BareCallCode:
 	case Kind::BareDelegateCall:
+	case Kind::BareStaticCall:
 	case Kind::ECRecover:
 	case Kind::SHA256:
 	case Kind::RIPEMD160:
@@ -2863,6 +2924,17 @@ string FunctionType::externalSignature() const
 {
 	solAssert(m_declaration != nullptr, "External signature of function needs declaration");
 	solAssert(!m_declaration->name().empty(), "Fallback function has no signature.");
+	switch (kind())
+	{
+	case Kind::Internal:
+	case Kind::External:
+	case Kind::CallCode:
+	case Kind::DelegateCall:
+	case Kind::Event:
+		break;
+	default:
+		solAssert(false, "Invalid function type for requesting external signature.");
+	}
 
 	bool const inLibrary = dynamic_cast<ContractDefinition const&>(*m_declaration->scope()).isLibrary();
 	FunctionTypePointer external = interfaceFunctionType();
@@ -2899,7 +2971,8 @@ bool FunctionType::isPure() const
 		m_kind == Kind::ABIEncode ||
 		m_kind == Kind::ABIEncodePacked ||
 		m_kind == Kind::ABIEncodeWithSelector ||
-		m_kind == Kind::ABIEncodeWithSignature;
+		m_kind == Kind::ABIEncodeWithSignature ||
+		m_kind == Kind::ABIDecode;
 }
 
 TypePointers FunctionType::parseElementaryTypeVector(strings const& _types)
@@ -2992,6 +3065,7 @@ bool FunctionType::padArguments() const
 	case Kind::BareCall:
 	case Kind::BareCallCode:
 	case Kind::BareDelegateCall:
+	case Kind::BareStaticCall:
 	case Kind::SHA256:
 	case Kind::RIPEMD160:
 	case Kind::KECCAK256:
@@ -3253,6 +3327,15 @@ MemberList::MemberMap MagicType::nativeMembers(ContractDefinition const*) const
 				FunctionType::Kind::ABIEncodeWithSignature,
 				true,
 				StateMutability::Pure
+			)},
+			{"decode", make_shared<FunctionType>(
+				TypePointers(),
+				TypePointers(),
+				strings{},
+				strings{},
+				FunctionType::Kind::ABIDecode,
+				true,
+				StateMutability::Pure
 			)}
 		});
 	default:

libsolidity/ast/Types.h

@@ -423,12 +423,12 @@ public:
 
 	virtual Category category() const override { return Category::RationalNumber; }
 
-	/// @returns true if the literal is a valid integer.
-	static std::tuple<bool, rational> isValidLiteral(Literal const& _literal);
+	static TypePointer forLiteral(Literal const& _literal);
 
-	explicit RationalNumberType(rational const& _value):
-		m_value(_value)
+	explicit RationalNumberType(rational const& _value, TypePointer const& _compatibleBytesType = TypePointer()):
+		m_value(_value), m_compatibleBytesType(_compatibleBytesType)
 	{}
+
 	virtual bool isImplicitlyConvertibleTo(Type const& _convertTo) const override;
 	virtual bool isExplicitlyConvertibleTo(Type const& _convertTo) const override;
 	virtual TypePointer unaryOperatorResult(Token::Value _operator) const override;
@@ -446,7 +446,8 @@ public:
 
 	/// @returns the smallest integer type that can hold the value or an empty pointer if not possible.
 	std::shared_ptr<IntegerType const> integerType() const;
-	/// @returns the smallest fixed type that can  hold the value or incurs the least precision loss.
+	/// @returns the smallest fixed type that can  hold the value or incurs the least precision loss,
+	/// unless the value was truncated, then a suitable type will be chosen to indicate such event.
 	/// If the integer part does not fit, returns an empty pointer.
 	std::shared_ptr<FixedPointType const> fixedPointType() const;
 
@@ -462,6 +463,13 @@ public:
 private:
 	rational m_value;
 
+	/// Bytes type to which the rational can be explicitly converted.
+	/// Empty for all rationals that are not directly parsed from hex literals.
+	TypePointer m_compatibleBytesType;
+
+	/// @returns true if the literal is a valid integer.
+	static std::tuple<bool, rational> isValidLiteral(Literal const& _literal);
+
 	/// @returns true if the literal is a valid rational number.
 	static std::tuple<bool, rational> parseRational(std::string const& _value);
 
@@ -896,6 +904,7 @@ public:
 		BareCall, ///< CALL without function hash
 		BareCallCode, ///< CALLCODE without function hash
 		BareDelegateCall, ///< DELEGATECALL without function hash
+		BareStaticCall, ///< STATICCALL without function hash
 		Creation, ///< external call using CREATE
 		Send, ///< CALL, but without data and gas
 		Transfer, ///< CALL, but without data and throws on error
@@ -926,7 +935,8 @@ public:
 		ABIEncodePacked,
 		ABIEncodeWithSelector,
 		ABIEncodeWithSignature,
-		GasLeft ///< gasleft()
+		ABIDecode,
+		GasLeft, ///< gasleft()
 	};
 
 	virtual Category category() const override { return Category::Function; }
@@ -1005,6 +1015,7 @@ public:
 
 	virtual std::string richIdentifier() const override;
 	virtual bool operator==(Type const& _other) const override;
+	virtual bool isImplicitlyConvertibleTo(Type const& _convertTo) const override;
 	virtual bool isExplicitlyConvertibleTo(Type const& _convertTo) const override;
 	virtual TypePointer unaryOperatorResult(Token::Value _operator) const override;
 	virtual TypePointer binaryOperatorResult(Token::Value, TypePointer const&) const override;
@@ -1034,10 +1045,14 @@ public:
 	/// @param _selfType if the function is bound, this has to be supplied and is the type of the
 	/// expression the function is called on.
 	bool canTakeArguments(TypePointers const& _arguments, TypePointer const& _selfType = TypePointer()) const;
-	/// @returns true if the types of parameters are equal (doesn't check return parameter types)
+	/// @returns true if the types of parameters are equal (does not check return parameter types)
 	bool hasEqualParameterTypes(FunctionType const& _other) const;
+	/// @returns true iff the return types are equal (does not check parameter types)
+	bool hasEqualReturnTypes(FunctionType const& _other) const;
+	/// @returns true iff the function type is equal to the given type, ignoring state mutability differences.
+	bool equalExcludingStateMutability(FunctionType const& _other) const;
 
-	/// @returns true if the ABI is used for this call (only meaningful for external calls)
+	/// @returns true if the ABI is NOT used for this call (only meaningful for external calls)
 	bool isBareCall() const;
 	Kind const& kind() const { return m_kind; }
 	StateMutability stateMutability() const { return m_stateMutability; }
@@ -1076,6 +1091,7 @@ public:
 		case FunctionType::Kind::BareCall:
 		case FunctionType::Kind::BareCallCode:
 		case FunctionType::Kind::BareDelegateCall:
+		case FunctionType::Kind::BareStaticCall:
 			return true;
 		default:
 			return false;

libsolidity/codegen/ExpressionCompiler.cpp

@@ -571,6 +571,7 @@ bool ExpressionCompiler::visit(FunctionCall const& _functionCall)
 		case FunctionType::Kind::BareCall:
 		case FunctionType::Kind::BareCallCode:
 		case FunctionType::Kind::BareDelegateCall:
+		case FunctionType::Kind::BareStaticCall:
 			_functionCall.expression().accept(*this);
 			appendExternalFunctionCall(function, arguments);
 			break;
@@ -1070,6 +1071,27 @@ bool ExpressionCompiler::visit(FunctionCall const& _functionCall)
 			// stack now: <memory pointer>
 			break;
 		}
+		case FunctionType::Kind::ABIDecode:
+		{
+			arguments.front()->accept(*this);
+			TypePointer firstArgType = arguments.front()->annotation().type;
+			TypePointers const& targetTypes = dynamic_cast<TupleType const&>(*_functionCall.annotation().type).components();
+			if (
+				*firstArgType == ArrayType(DataLocation::CallData) ||
+				*firstArgType == ArrayType(DataLocation::CallData, true)
+			)
+				utils().abiDecode(targetTypes, false);
+			else
+			{
+				utils().convertType(*firstArgType, ArrayType(DataLocation::Memory));
+				m_context << Instruction::DUP1 << u256(32) << Instruction::ADD;
+				m_context << Instruction::SWAP1 << Instruction::MLOAD;
+				// stack now: <mem_pos> <length>
+
+				utils().abiDecode(targetTypes, true);
+			}
+			break;
+		}
 		case FunctionType::Kind::GasLeft:
 			m_context << Instruction::GAS;
 			break;
@@ -1143,18 +1165,19 @@ bool ExpressionCompiler::visit(MemberAccess const& _memberAccess)
 						solAssert(false, "event not found");
 					// no-op, because the parent node will do the job
 					break;
+				case FunctionType::Kind::DelegateCall:
+					_memberAccess.expression().accept(*this);
+					m_context << funType->externalIdentifier();
+					break;
+				case FunctionType::Kind::CallCode:
 				case FunctionType::Kind::External:
 				case FunctionType::Kind::Creation:
-				case FunctionType::Kind::DelegateCall:
-				case FunctionType::Kind::CallCode:
 				case FunctionType::Kind::Send:
 				case FunctionType::Kind::BareCall:
 				case FunctionType::Kind::BareCallCode:
 				case FunctionType::Kind::BareDelegateCall:
+				case FunctionType::Kind::BareStaticCall:
 				case FunctionType::Kind::Transfer:
-					_memberAccess.expression().accept(*this);
-					m_context << funType->externalIdentifier();
-					break;
 				case FunctionType::Kind::Log0:
 				case FunctionType::Kind::Log1:
 				case FunctionType::Kind::Log2:
@@ -1252,7 +1275,7 @@ bool ExpressionCompiler::visit(MemberAccess const& _memberAccess)
 			);
 			m_context << Instruction::BALANCE;
 		}
-		else if ((set<string>{"send", "transfer", "call", "callcode", "delegatecall"}).count(member))
+		else if ((set<string>{"send", "transfer", "call", "callcode", "delegatecall", "staticcall"}).count(member))
 			utils().convertType(
 				*_memberAccess.expression().annotation().type,
 				IntegerType(160, IntegerType::Modifier::Address),
@@ -1804,10 +1827,13 @@ void ExpressionCompiler::appendExternalFunctionCall(
 		utils().moveToStackTop(gasValueSize, _functionType.selfType()->sizeOnStack());
 
 	auto funKind = _functionType.kind();
-	bool returnSuccessCondition = funKind == FunctionType::Kind::BareCall || funKind == FunctionType::Kind::BareCallCode || funKind == FunctionType::Kind::BareDelegateCall;
+
+	solAssert(funKind != FunctionType::Kind::BareStaticCall || m_context.evmVersion().hasStaticCall(), "");
+	
+	bool returnSuccessCondition = funKind == FunctionType::Kind::BareCall || funKind == FunctionType::Kind::BareCallCode || funKind == FunctionType::Kind::BareDelegateCall || funKind == FunctionType::Kind::BareStaticCall;
 	bool isCallCode = funKind == FunctionType::Kind::BareCallCode || funKind == FunctionType::Kind::CallCode;
 	bool isDelegateCall = funKind == FunctionType::Kind::BareDelegateCall || funKind == FunctionType::Kind::DelegateCall;
-	bool useStaticCall = _functionType.stateMutability() <= StateMutability::View && m_context.evmVersion().hasStaticCall();
+	bool useStaticCall = funKind == FunctionType::Kind::BareStaticCall || (_functionType.stateMutability() <= StateMutability::View && m_context.evmVersion().hasStaticCall());
 
 	bool haveReturndatacopy = m_context.evmVersion().supportsReturndata();
 	unsigned retSize = 0;

libsolidity/interface/CompilerStack.cpp

@@ -58,22 +58,31 @@ using namespace std;
 using namespace dev;
 using namespace dev::solidity;
 
-void CompilerStack::setRemappings(vector<string> const& _remappings)
+boost::optional<CompilerStack::Remapping> CompilerStack::parseRemapping(string const& _remapping)
+{
+	auto eq = find(_remapping.begin(), _remapping.end(), '=');
+	if (eq == _remapping.end())
+		return {};
+
+	auto colon = find(_remapping.begin(), eq, ':');
+
+	Remapping r;
+
+	r.context = colon == eq ? string() : string(_remapping.begin(), colon);
+	r.prefix = colon == eq ? string(_remapping.begin(), eq) : string(colon + 1, eq);
+	r.target = string(eq + 1, _remapping.end());
+
+	if (r.prefix.empty())
+		return {};
+
+	return r;
+}
+
+void CompilerStack::setRemappings(vector<Remapping> const& _remappings)
 {
-	vector<Remapping> remappings;
 	for (auto const& remapping: _remappings)
-	{
-		auto eq = find(remapping.begin(), remapping.end(), '=');
-		if (eq == remapping.end())
-			continue; // ignore
-		auto colon = find(remapping.begin(), eq, ':');
-		Remapping r;
-		r.context = colon == eq ? string() : string(remapping.begin(), colon);
-		r.prefix = colon == eq ? string(remapping.begin(), eq) : string(colon + 1, eq);
-		r.target = string(eq + 1, remapping.end());
-		remappings.push_back(r);
-	}
-	swap(m_remappings, remappings);
+		solAssert(!remapping.prefix.empty(), "");
+	m_remappings = _remappings;
 }
 
 void CompilerStack::setEVMVersion(EVMVersion _version)

libsolidity/interface/CompilerStack.h

@@ -84,6 +84,13 @@ public:
 		CompilationSuccessful
 	};
 
+	struct Remapping
+	{
+		std::string context;
+		std::string prefix;
+		std::string target;
+	};
+
 	/// Creates a new compiler stack.
 	/// @param _readFile callback to used to read files for import statements. Must return
 	/// and must not emit exceptions.
@@ -103,8 +110,11 @@ public:
 	/// All settings, with the exception of remappings, are reset.
 	void reset(bool _keepSources = false);
 
-	/// Sets path remappings in the format "context:prefix=target"
-	void setRemappings(std::vector<std::string> const& _remappings);
+	// Parses a remapping of the format "context:prefix=target".
+	static boost::optional<Remapping> parseRemapping(std::string const& _remapping);
+
+	/// Sets path remappings.
+	void setRemappings(std::vector<Remapping> const& _remappings);
 
 	/// Sets library addresses. Addresses are cleared iff @a _libraries is missing.
 	/// Will not take effect before running compile.
@@ -319,13 +329,6 @@ private:
 		FunctionDefinition const& _function
 	) const;
 
-	struct Remapping
-	{
-		std::string context;
-		std::string prefix;
-		std::string target;
-	};
-
 	ReadCallback::Callback m_readFile;
 	ReadCallback::Callback m_smtQuery;
 	bool m_optimize = false;

libsolidity/interface/Natspec.cpp

@@ -36,6 +36,15 @@ Json::Value Natspec::userDocumentation(ContractDefinition const& _contractDef)
 	Json::Value doc;
 	Json::Value methods(Json::objectValue);
 
+	auto constructorDefinition(_contractDef.constructor());
+	if (constructorDefinition)
+	{
+		string value = extractDoc(constructorDefinition->annotation().docTags, "notice");
+		if (!value.empty())
+			// add the constructor, only if we have any documentation to add
+			methods["constructor"] = Json::Value(value);
+	}
+
 	string notice = extractDoc(_contractDef.annotation().docTags, "notice");
 	if (!notice.empty())
 		doc["notice"] = Json::Value(notice);
@@ -73,33 +82,21 @@ Json::Value Natspec::devDocumentation(ContractDefinition const& _contractDef)
 	if (!dev.empty())
 		doc["details"] = Json::Value(dev);
 
+	auto constructorDefinition(_contractDef.constructor());
+	if (constructorDefinition) {
+		Json::Value constructor(devDocumentation(constructorDefinition->annotation().docTags));
+		if (!constructor.empty())
+			// add the constructor, only if we have any documentation to add
+			methods["constructor"] = constructor;
+	}
+
 	for (auto const& it: _contractDef.interfaceFunctions())
 	{
 		if (!it.second->hasDeclaration())
 			continue;
-		Json::Value method;
 		if (auto fun = dynamic_cast<FunctionDefinition const*>(&it.second->declaration()))
 		{
-			auto dev = extractDoc(fun->annotation().docTags, "dev");
-			if (!dev.empty())
-				method["details"] = Json::Value(dev);
-
-			auto author = extractDoc(fun->annotation().docTags, "author");
-			if (!author.empty())
-				method["author"] = author;
-
-			auto ret = extractDoc(fun->annotation().docTags, "return");
-			if (!ret.empty())
-				method["return"] = ret;
-
-			Json::Value params(Json::objectValue);
-			auto paramRange = fun->annotation().docTags.equal_range("param");
-			for (auto i = paramRange.first; i != paramRange.second; ++i)
-				params[i->second.paramName] = Json::Value(i->second.content);
-
-			if (!params.empty())
-				method["params"] = params;
-
+			Json::Value method(devDocumentation(fun->annotation().docTags));
 			if (!method.empty())
 				// add the function, only if we have any documentation to add
 				methods[it.second->externalSignature()] = method;
@@ -118,3 +115,31 @@ string Natspec::extractDoc(multimap<string, DocTag> const& _tags, string const&
 		value += i->second.content;
 	return value;
 }
+
+Json::Value Natspec::devDocumentation(std::multimap<std::string, DocTag> const &_tags)
+{
+	Json::Value json(Json::objectValue);
+	auto dev = extractDoc(_tags, "dev");
+	if (!dev.empty())
+		json["details"] = Json::Value(dev);
+
+	auto author = extractDoc(_tags, "author");
+	if (!author.empty())
+		json["author"] = author;
+
+	// for constructors, the "return" node will never exist. invalid tags
+	// will already generate an error within dev::solidity::DocStringAnalyzer.
+	auto ret = extractDoc(_tags, "return");
+	if (!ret.empty())
+		json["return"] = ret;
+
+	Json::Value params(Json::objectValue);
+	auto paramRange = _tags.equal_range("param");
+	for (auto i = paramRange.first; i != paramRange.second; ++i)
+		params[i->second.paramName] = Json::Value(i->second.content);
+
+	if (!params.empty())
+		json["params"] = params;
+
+	return json;
+}

libsolidity/interface/Natspec.h

@@ -54,6 +54,12 @@ public:
 private:
 	/// @returns concatenation of all content under the given tag name.
 	static std::string extractDoc(std::multimap<std::string, DocTag> const& _tags, std::string const& _name);
+
+	/// Helper-function that will create a json object with dev specific annotations, if present.
+	/// @param _tags docTags that are used.
+	/// @return      A JSON representation
+	///              of the contract's developer documentation
+	static Json::Value devDocumentation(std::multimap<std::string, DocTag> const &_tags);
 };
 
 } //solidity NS

libsolidity/interface/StandardCompiler.cpp

@@ -326,9 +326,14 @@ Json::Value StandardCompiler::compileInternal(Json::Value const& _input)
 		m_compilerStack.setEVMVersion(*version);
 	}
 
-	vector<string> remappings;
+	vector<CompilerStack::Remapping> remappings;
 	for (auto const& remapping: settings.get("remappings", Json::Value()))
-		remappings.push_back(remapping.asString());
+	{
+		if (auto r = CompilerStack::parseRemapping(remapping.asString()))
+			remappings.emplace_back(std::move(*r));
+		else
+			return formatFatalError("JSONError", "Invalid remapping: \"" + remapping.asString() + "\"");
+	}
 	m_compilerStack.setRemappings(remappings);
 
 	Json::Value optimizerSettings = settings.get("optimizer", Json::Value());