/* This file is part of solidity. solidity is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. solidity is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with solidity. If not, see . */ // SPDX-License-Identifier: GPL-3.0 /** * @author Christian * @date 2015 * Type analyzer and checker. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; using namespace solidity; using namespace solidity::util; using namespace solidity::langutil; using namespace solidity::frontend; bool TypeChecker::typeSupportedByOldABIEncoder(Type const& _type, bool _isLibraryCall) { if (_isLibraryCall && _type.dataStoredIn(DataLocation::Storage)) return true; if (_type.category() == Type::Category::Struct) return false; if (_type.category() == Type::Category::Array) { auto const& arrayType = dynamic_cast(_type); auto base = arrayType.baseType(); if (!typeSupportedByOldABIEncoder(*base, _isLibraryCall) || (base->category() == Type::Category::Array && base->isDynamicallySized())) return false; } return true; } bool TypeChecker::checkTypeRequirements(SourceUnit const& _source) { m_currentSourceUnit = &_source; _source.accept(*this); m_currentSourceUnit = nullptr; return Error::containsOnlyWarnings(m_errorReporter.errors()); } TypePointer const& TypeChecker::type(Expression const& _expression) const { solAssert(!!_expression.annotation().type, "Type requested but not present."); return _expression.annotation().type; } TypePointer const& TypeChecker::type(VariableDeclaration const& _variable) const { solAssert(!!_variable.annotation().type, "Type requested but not present."); return _variable.annotation().type; } bool TypeChecker::visit(ContractDefinition const& _contract) { m_currentContract = &_contract; ASTNode::listAccept(_contract.baseContracts(), *this); for (auto const& n: _contract.subNodes()) n->accept(*this); m_currentContract = nullptr; return false; } void TypeChecker::checkDoubleStorageAssignment(Assignment const& _assignment) { TupleType const& lhs = dynamic_cast(*type(_assignment.leftHandSide())); TupleType const& rhs = dynamic_cast(*type(_assignment.rightHandSide())); if (lhs.components().size() != rhs.components().size()) { solAssert(m_errorReporter.hasErrors(), ""); return; } size_t storageToStorageCopies = 0; size_t toStorageCopies = 0; for (size_t i = 0; i < lhs.components().size(); ++i) { ReferenceType const* ref = dynamic_cast(lhs.components()[i]); if (!ref || !ref->dataStoredIn(DataLocation::Storage) || ref->isPointer()) continue; toStorageCopies++; if (rhs.components()[i]->dataStoredIn(DataLocation::Storage)) storageToStorageCopies++; } if (storageToStorageCopies >= 1 && toStorageCopies >= 2) m_errorReporter.warning( 7238_error, _assignment.location(), "This assignment performs two copies to storage. Since storage copies do not first " "copy to a temporary location, one of them might be overwritten before the second " "is executed and thus may have unexpected effects. It is safer to perform the copies " "separately or assign to storage pointers first." ); } TypePointers TypeChecker::typeCheckABIDecodeAndRetrieveReturnType(FunctionCall const& _functionCall, bool _abiEncoderV2) { vector> arguments = _functionCall.arguments(); if (arguments.size() != 2) m_errorReporter.typeError( 5782_error, _functionCall.location(), "This function takes two arguments, but " + toString(arguments.size()) + " were provided." ); if (arguments.size() >= 1) if ( !type(*arguments.front())->isImplicitlyConvertibleTo(*TypeProvider::bytesMemory()) && !type(*arguments.front())->isImplicitlyConvertibleTo(*TypeProvider::bytesCalldata()) ) m_errorReporter.typeError( 1956_error, arguments.front()->location(), "The first argument to \"abi.decode\" must be implicitly convertible to " "bytes memory or bytes calldata, but is of type " + type(*arguments.front())->toString() + "." ); if (arguments.size() < 2) return {}; // 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(arguments[1].get()); if (!tupleExpression) { m_errorReporter.typeError( 6444_error, arguments[1]->location(), "The second argument to \"abi.decode\" has to be a tuple of types." ); return {}; } TypePointers components; for (auto const& typeArgument: tupleExpression->components()) { solAssert(typeArgument, ""); if (TypeType const* argTypeType = dynamic_cast(type(*typeArgument))) { 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 = TypeProvider::withLocationIfReference(DataLocation::Memory, actualType); // We force address payable for address types. if (actualType->category() == Type::Category::Address) actualType = TypeProvider::payableAddress(); solAssert( !actualType->dataStoredIn(DataLocation::CallData) && !actualType->dataStoredIn(DataLocation::Storage), "" ); if (!actualType->fullEncodingType(false, _abiEncoderV2, false)) m_errorReporter.typeError( 9611_error, typeArgument->location(), "Decoding type " + actualType->toString(false) + " not supported." ); if (auto referenceType = dynamic_cast(actualType)) { auto result = referenceType->validForLocation(referenceType->location()); if (!result) m_errorReporter.typeError( 6118_error, typeArgument->location(), result.message() ); } components.push_back(actualType); } else { m_errorReporter.typeError(1039_error, typeArgument->location(), "Argument has to be a type name."); components.push_back(TypeProvider::emptyTuple()); } } return components; } TypePointers TypeChecker::typeCheckMetaTypeFunctionAndRetrieveReturnType(FunctionCall const& _functionCall) { vector> arguments = _functionCall.arguments(); if (arguments.size() != 1) { m_errorReporter.typeError( 8885_error, _functionCall.location(), "This function takes one argument, but " + toString(arguments.size()) + " were provided." ); return {}; } TypePointer firstArgType = type(*arguments.front()); bool wrongType = false; if (firstArgType->category() == Type::Category::TypeType) { TypeType const* typeTypePtr = dynamic_cast(firstArgType); Type::Category typeCategory = typeTypePtr->actualType()->category(); if ( typeCategory != Type::Category::Contract && typeCategory != Type::Category::Integer ) wrongType = true; } else wrongType = true; if (wrongType) { m_errorReporter.typeError( 4259_error, arguments.front()->location(), "Invalid type for argument in the function call. " "A contract type or an integer type is required, but " + type(*arguments.front())->toString(true) + " provided." ); return {}; } return {TypeProvider::meta(dynamic_cast(*firstArgType).actualType())}; } void TypeChecker::endVisit(InheritanceSpecifier const& _inheritance) { auto base = dynamic_cast(&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."); if (base->isLibrary()) m_errorReporter.typeError(2571_error, _inheritance.location(), "Libraries cannot be inherited from."); auto const& arguments = _inheritance.arguments(); TypePointers parameterTypes; if (!base->isInterface()) // Interfaces do not have constructors, so there are zero parameters. parameterTypes = ContractType(*base).newExpressionType()->parameterTypes(); if (arguments) { if (parameterTypes.size() != arguments->size()) { m_errorReporter.typeError( 7927_error, _inheritance.location(), "Wrong argument count for constructor call: " + toString(arguments->size()) + " arguments given but expected " + toString(parameterTypes.size()) + ". Remove parentheses if you do not want to provide arguments here." ); } for (size_t i = 0; i < std::min(arguments->size(), parameterTypes.size()); ++i) { BoolResult result = type(*(*arguments)[i])->isImplicitlyConvertibleTo(*parameterTypes[i]); if (!result) m_errorReporter.typeErrorConcatenateDescriptions( 9827_error, (*arguments)[i]->location(), "Invalid type for argument in constructor call. " "Invalid implicit conversion from " + type(*(*arguments)[i])->toString() + " to " + parameterTypes[i]->toString() + " requested.", result.message() ); } } } void TypeChecker::endVisit(ModifierDefinition const& _modifier) { if (_modifier.virtualSemantics()) if (auto const* contractDef = dynamic_cast(_modifier.scope())) if (contractDef->isLibrary()) m_errorReporter.typeError( 3275_error, _modifier.location(), "Modifiers in a library cannot be virtual." ); if (!_modifier.isImplemented() && !_modifier.virtualSemantics()) m_errorReporter.typeError(8063_error, _modifier.location(), "Modifiers without implementation must be marked virtual."); } bool TypeChecker::visit(FunctionDefinition const& _function) { if (_function.markedVirtual()) { 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\""); else if (_function.visibility() == Visibility::Private) m_errorReporter.typeError(3942_error, _function.location(), "\"virtual\" and \"private\" cannot be used together."); 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."); 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."); } vector internalParametersInConstructor; auto checkArgumentAndReturnParameter = [&](VariableDeclaration const& _var) { if (type(_var)->containsNestedMapping()) if (_var.referenceLocation() == VariableDeclaration::Location::Storage) solAssert( _function.libraryFunction() || _function.isConstructor() || !_function.isPublic(), "Mapping types for parameters or return variables " "can only be used in internal or library functions." ); bool functionIsExternallyVisible = (!_function.isConstructor() && _function.isPublic()) || (_function.isConstructor() && !m_currentContract->abstract()); if ( _function.isConstructor() && _var.referenceLocation() == VariableDeclaration::Location::Storage && !m_currentContract->abstract() ) m_errorReporter.typeError( 3644_error, _var.location(), "This parameter has a type that can only be used internally. " "You can make the contract abstract to avoid this problem." ); else if (functionIsExternallyVisible) { auto iType = type(_var)->interfaceType(_function.libraryFunction()); if (!iType) { string message = iType.message(); solAssert(!message.empty(), "Expected detailed error message!"); if (_function.isConstructor()) message += " You can make the contract abstract to avoid this problem."; m_errorReporter.typeError(4103_error, _var.location(), message); } else if ( !experimentalFeatureActive(ExperimentalFeature::ABIEncoderV2) && !typeSupportedByOldABIEncoder(*type(_var), _function.libraryFunction()) ) { string message = "This type is only supported in ABIEncoderV2. " "Use \"pragma experimental ABIEncoderV2;\" to enable the feature."; if (_function.isConstructor()) message += " Alternatively, make the contract abstract and supply the " "constructor arguments from a derived contract."; m_errorReporter.typeError( 4957_error, _var.location(), message ); } } }; for (ASTPointer const& var: _function.parameters()) { checkArgumentAndReturnParameter(*var); var->accept(*this); } for (ASTPointer const& var: _function.returnParameters()) { checkArgumentAndReturnParameter(*var); var->accept(*this); } set modifiers; for (ASTPointer const& modifier: _function.modifiers()) { vector baseContracts; if (auto contract = dynamic_cast(_function.scope())) { baseContracts = contract->annotation().linearizedBaseContracts; // Delete first base which is just the main contract itself baseContracts.erase(baseContracts.begin()); } visitManually( *modifier, _function.isConstructor() ? baseContracts : vector() ); Declaration const* decl = &dereference(*modifier->name()); if (modifiers.count(decl)) { if (dynamic_cast(decl)) m_errorReporter.declarationError(1697_error, modifier->location(), "Base constructor already provided."); } else modifiers.insert(decl); } 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."); if (_function.isConstructor()) m_errorReporter.typeError(6482_error, _function.location(), "Constructor cannot be defined in interfaces."); else if (_function.visibility() != Visibility::External) m_errorReporter.typeError(1560_error, _function.location(), "Functions in interfaces must be declared external."); } 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()) m_errorReporter.typeError(5700_error, _function.location(), "Constructor must be implemented if declared."); else if (_function.libraryFunction()) m_errorReporter.typeError(9231_error, _function.location(), "Library functions must be implemented if declared."); else if (!_function.virtualSemantics()) { 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()) typeCheckFallbackFunction(_function); else if (_function.isReceive()) typeCheckReceiveFunction(_function); else if (_function.isConstructor()) typeCheckConstructor(_function); return false; } bool TypeChecker::visit(VariableDeclaration const& _variable) { _variable.typeName().accept(*this); // type is filled either by ReferencesResolver directly from the type name or by // TypeChecker at the VariableDeclarationStatement level. TypePointer varType = _variable.annotation().type; solAssert(!!varType, "Variable type not provided."); if (auto contractType = dynamic_cast(varType)) if (contractType->contractDefinition().isLibrary()) m_errorReporter.typeError(1273_error, _variable.location(), "The type of a variable cannot be a library."); if (_variable.value()) { if (_variable.isStateVariable() && varType->containsNestedMapping()) { m_errorReporter.typeError( 6280_error, _variable.location(), "Types in storage containing (nested) mappings cannot be assigned to." ); _variable.value()->accept(*this); } else expectType(*_variable.value(), *varType); } if (_variable.isConstant()) { if (!_variable.type()->isValueType()) { bool allowed = false; if (auto arrayType = dynamic_cast(_variable.type())) allowed = arrayType->isByteArray(); if (!allowed) m_errorReporter.typeError(9259_error, _variable.location(), "Constants of non-value type not yet implemented."); } if (!_variable.value()) m_errorReporter.typeError(4266_error, _variable.location(), "Uninitialized \"constant\" variable."); else if (!*_variable.value()->annotation().isPure) m_errorReporter.typeError( 8349_error, _variable.value()->location(), "Initial value for constant variable has to be compile-time constant." ); } else if (_variable.immutable()) { if (!_variable.type()->isValueType()) m_errorReporter.typeError(6377_error, _variable.location(), "Immutable variables cannot have a non-value type."); if ( auto const* functionType = dynamic_cast(_variable.type()); functionType && functionType->kind() == FunctionType::Kind::External ) m_errorReporter.typeError(3366_error, _variable.location(), "Immutable variables of external function type are not yet supported."); solAssert(_variable.type()->sizeOnStack() == 1 || m_errorReporter.hasErrors(), ""); } if (!_variable.isStateVariable()) { if ( _variable.referenceLocation() == VariableDeclaration::Location::CallData || _variable.referenceLocation() == VariableDeclaration::Location::Memory ) if (varType->containsNestedMapping()) m_errorReporter.fatalTypeError( 4061_error, _variable.location(), "Type " + varType->toString(true) + " is only valid in storage because it contains a (nested) mapping." ); } else if (_variable.visibility() >= Visibility::Public) { FunctionType getter(_variable); if (!experimentalFeatureActive(ExperimentalFeature::ABIEncoderV2)) { vector unsupportedTypes; for (auto const& param: getter.parameterTypes() + getter.returnParameterTypes()) if (!typeSupportedByOldABIEncoder(*param, false /* isLibrary */)) unsupportedTypes.emplace_back(param->toString()); if (!unsupportedTypes.empty()) m_errorReporter.typeError( 2763_error, _variable.location(), "The following types are only supported for getters in ABIEncoderV2: " + joinHumanReadable(unsupportedTypes) + ". Either remove \"public\" or use \"pragma experimental ABIEncoderV2;\" to enable the feature." ); } if (!getter.interfaceFunctionType()) m_errorReporter.typeError(6744_error, _variable.location(), "Internal or recursive type is not allowed for public state variables."); } bool isStructMemberDeclaration = dynamic_cast(_variable.scope()) != nullptr; if (isStructMemberDeclaration) return false; if (auto referenceType = dynamic_cast(varType)) { auto result = referenceType->validForLocation(referenceType->location()); if (result) { bool isLibraryStorageParameter = (_variable.isLibraryFunctionParameter() && referenceType->location() == DataLocation::Storage); bool callDataCheckRequired = ((_variable.isConstructorParameter() || _variable.isPublicCallableParameter()) && !isLibraryStorageParameter); if (callDataCheckRequired) result = referenceType->validForLocation(DataLocation::CallData); } if (!result) { solAssert(!result.message().empty(), "Expected detailed error message"); m_errorReporter.typeError(1534_error, _variable.location(), result.message()); return false; } } return false; } void TypeChecker::visitManually( ModifierInvocation const& _modifier, vector const& _bases ) { std::vector> const& arguments = _modifier.arguments() ? *_modifier.arguments() : std::vector>(); for (ASTPointer const& argument: arguments) argument->accept(*this); _modifier.name()->accept(*this); auto const* declaration = &dereference(*_modifier.name()); vector> emptyParameterList; vector> const* parameters = nullptr; if (auto modifierDecl = dynamic_cast(declaration)) parameters = &modifierDecl->parameters(); else // check parameters for Base constructors for (ContractDefinition const* base: _bases) if (declaration == base) { if (auto referencedConstructor = base->constructor()) parameters = &referencedConstructor->parameters(); else parameters = &emptyParameterList; break; } if (!parameters) { m_errorReporter.typeError(4659_error, _modifier.location(), "Referenced declaration is neither modifier nor base class."); return; } if (parameters->size() != arguments.size()) { m_errorReporter.typeError( 2973_error, _modifier.location(), "Wrong argument count for modifier invocation: " + toString(arguments.size()) + " arguments given but expected " + toString(parameters->size()) + "." ); return; } for (size_t i = 0; i < arguments.size(); ++i) { BoolResult result = type(*arguments[i])->isImplicitlyConvertibleTo(*type(*(*parameters)[i])); if (!result) m_errorReporter.typeErrorConcatenateDescriptions( 4649_error, arguments[i]->location(), "Invalid type for argument in modifier invocation. " "Invalid implicit conversion from " + type(*arguments[i])->toString() + " to " + type(*(*parameters)[i])->toString() + " requested.", result.message() ); } } bool TypeChecker::visit(EventDefinition const& _eventDef) { solAssert(_eventDef.visibility() > Visibility::Internal, ""); unsigned numIndexed = 0; for (ASTPointer const& var: _eventDef.parameters()) { if (var->isIndexed()) numIndexed++; if (type(*var)->containsNestedMapping()) m_errorReporter.typeError( 3448_error, var->location(), "Type containing a (nested) mapping is not allowed as event parameter type." ); if (!type(*var)->interfaceType(false)) m_errorReporter.typeError(3417_error, var->location(), "Internal or recursive type is not allowed as event parameter type."); if ( !experimentalFeatureActive(ExperimentalFeature::ABIEncoderV2) && !typeSupportedByOldABIEncoder(*type(*var), false /* isLibrary */) ) m_errorReporter.typeError( 3061_error, var->location(), "This type is only supported in ABIEncoderV2. " "Use \"pragma experimental ABIEncoderV2;\" to enable the feature." ); } if (_eventDef.isAnonymous() && numIndexed > 4) m_errorReporter.typeError(8598_error, _eventDef.location(), "More than 4 indexed arguments for anonymous event."); else if (!_eventDef.isAnonymous() && numIndexed > 3) m_errorReporter.typeError(7249_error, _eventDef.location(), "More than 3 indexed arguments for event."); return true; } void TypeChecker::endVisit(FunctionTypeName const& _funType) { FunctionType const& fun = dynamic_cast(*_funType.annotation().type); if (fun.kind() == FunctionType::Kind::External) { for (auto const& t: _funType.parameterTypes() + _funType.returnParameterTypes()) { solAssert(t->annotation().type, "Type not set for parameter."); if (!t->annotation().type->interfaceType(false).get()) m_errorReporter.typeError(2582_error, t->location(), "Internal type cannot be used for external function type."); } solAssert(fun.interfaceType(false), "External function type uses internal types."); } } bool TypeChecker::visit(InlineAssembly const& _inlineAssembly) { // External references have already been resolved in a prior stage and stored in the annotation. // We run the resolve step again regardless. yul::ExternalIdentifierAccess::Resolver identifierAccess = [&]( yul::Identifier const& _identifier, yul::IdentifierContext _context, bool ) { auto ref = _inlineAssembly.annotation().externalReferences.find(&_identifier); if (ref == _inlineAssembly.annotation().externalReferences.end()) return false; InlineAssemblyAnnotation::ExternalIdentifierInfo& identifierInfo = ref->second; Declaration const* declaration = identifierInfo.declaration; solAssert(!!declaration, ""); bool requiresStorage = identifierInfo.isSlot || identifierInfo.isOffset; if (auto var = dynamic_cast(declaration)) { solAssert(var->type(), "Expected variable type!"); if (var->immutable()) { m_errorReporter.typeError(3773_error, _identifier.location, "Assembly access to immutable variables is not supported."); return false; } if (var->isConstant()) { var = rootConstVariableDeclaration(*var); if (var && !var->value()) { m_errorReporter.typeError(3224_error, _identifier.location, "Constant has no value."); return false; } else if (_context == yul::IdentifierContext::LValue) { m_errorReporter.typeError(6252_error, _identifier.location, "Constant variables cannot be assigned to."); return false; } else if (requiresStorage) { m_errorReporter.typeError(6617_error, _identifier.location, "The suffixes .offset and .slot can only be used on non-constant storage variables."); return false; } else if (var && var->value() && !var->value()->annotation().type && !dynamic_cast(var->value().get())) { m_errorReporter.typeError( 2249_error, _identifier.location, "Constant variables with non-literal values cannot be forward referenced from inline assembly." ); return false; } else if (!var || !type(*var)->isValueType() || ( !dynamic_cast(var->value().get()) && type(*var->value())->category() != Type::Category::RationalNumber )) { m_errorReporter.typeError(7615_error, _identifier.location, "Only direct number constants and references to such constants are supported by inline assembly."); return false; } } solAssert(!dynamic_cast(var->type()), "FixedPointType not implemented."); if (requiresStorage) { if (!var->isStateVariable() && !var->type()->dataStoredIn(DataLocation::Storage)) { m_errorReporter.typeError(3622_error, _identifier.location, "The suffixes .offset and .slot can only be used on storage variables."); return false; } else if (_context == yul::IdentifierContext::LValue) { if (var->isStateVariable()) { m_errorReporter.typeError(4713_error, _identifier.location, "State variables cannot be assigned to - you have to use \"sstore()\"."); return false; } else if (identifierInfo.isOffset) { m_errorReporter.typeError(9739_error, _identifier.location, "Only .slot can be assigned to."); return false; } else solAssert(identifierInfo.isSlot, ""); } } else if (!var->isConstant() && var->isStateVariable()) { m_errorReporter.typeError(1408_error, _identifier.location, "Only local variables are supported. To access storage variables, use the .slot and .offset suffixes."); return false; } else if (var->type()->dataStoredIn(DataLocation::Storage)) { m_errorReporter.typeError(9068_error, _identifier.location, "You have to use the .slot or .offset suffix to access storage reference variables."); return false; } else if (var->type()->sizeOnStack() != 1) { if (var->type()->dataStoredIn(DataLocation::CallData)) m_errorReporter.typeError(2370_error, _identifier.location, "Call data elements cannot be accessed directly. Copy to a local variable first or use \"calldataload\" or \"calldatacopy\" with manually determined offsets and sizes."); else m_errorReporter.typeError(9857_error, _identifier.location, "Only types that use one stack slot are supported."); return false; } } else if (requiresStorage) { m_errorReporter.typeError(7944_error, _identifier.location, "The suffixes .offset and .slot can only be used on storage variables."); return false; } else if (_context == yul::IdentifierContext::LValue) { if (dynamic_cast(declaration)) return false; m_errorReporter.typeError(1990_error, _identifier.location, "Only local variables can be assigned to in inline assembly."); return false; } if (_context == yul::IdentifierContext::RValue) { solAssert(!!declaration->type(), "Type of declaration required but not yet determined."); if (dynamic_cast(declaration)) { m_errorReporter.declarationError(2025_error, _identifier.location, "Access to functions is not allowed in inline assembly."); return false; } else if (dynamic_cast(declaration)) { } else if (auto contract = dynamic_cast(declaration)) { if (!contract->isLibrary()) { m_errorReporter.typeError(4977_error, _identifier.location, "Expected a library."); return false; } } else return false; } identifierInfo.valueSize = 1; return true; }; solAssert(!_inlineAssembly.annotation().analysisInfo, ""); _inlineAssembly.annotation().analysisInfo = make_shared(); yul::AsmAnalyzer analyzer( *_inlineAssembly.annotation().analysisInfo, m_errorReporter, _inlineAssembly.dialect(), identifierAccess ); if (!analyzer.analyze(_inlineAssembly.operations())) return false; return true; } bool TypeChecker::visit(IfStatement const& _ifStatement) { expectType(_ifStatement.condition(), *TypeProvider::boolean()); _ifStatement.trueStatement().accept(*this); if (_ifStatement.falseStatement()) _ifStatement.falseStatement()->accept(*this); return false; } void TypeChecker::endVisit(TryStatement const& _tryStatement) { FunctionCall const* externalCall = dynamic_cast(&_tryStatement.externalCall()); if (!externalCall || *externalCall->annotation().kind != FunctionCallKind::FunctionCall) { m_errorReporter.typeError( 5347_error, _tryStatement.externalCall().location(), "Try can only be used with external function calls and contract creation calls." ); return; } FunctionType const& functionType = dynamic_cast(*externalCall->expression().annotation().type); if ( functionType.kind() != FunctionType::Kind::External && functionType.kind() != FunctionType::Kind::Creation && functionType.kind() != FunctionType::Kind::DelegateCall ) { m_errorReporter.typeError( 2536_error, _tryStatement.externalCall().location(), "Try can only be used with external function calls and contract creation calls." ); return; } externalCall->annotation().tryCall = true; solAssert(_tryStatement.clauses().size() >= 2, ""); solAssert(_tryStatement.clauses().front(), ""); TryCatchClause const& successClause = *_tryStatement.clauses().front(); if (successClause.parameters()) { TypePointers returnTypes = m_evmVersion.supportsReturndata() ? functionType.returnParameterTypes() : functionType.returnParameterTypesWithoutDynamicTypes(); std::vector> const& parameters = successClause.parameters()->parameters(); if (returnTypes.size() != parameters.size()) m_errorReporter.typeError( 2800_error, successClause.location(), "Function returns " + to_string(functionType.returnParameterTypes().size()) + " values, but returns clause has " + to_string(parameters.size()) + " variables." ); size_t len = min(returnTypes.size(), parameters.size()); for (size_t i = 0; i < len; ++i) { solAssert(returnTypes[i], ""); if (parameters[i] && *parameters[i]->annotation().type != *returnTypes[i]) m_errorReporter.typeError( 6509_error, parameters[i]->location(), "Invalid type, expected " + returnTypes[i]->toString(false) + " but got " + parameters[i]->annotation().type->toString() + "." ); } } TryCatchClause const* errorClause = nullptr; TryCatchClause const* lowLevelClause = nullptr; for (size_t i = 1; i < _tryStatement.clauses().size(); ++i) { TryCatchClause const& clause = *_tryStatement.clauses()[i]; if (clause.errorName() == "") { if (lowLevelClause) m_errorReporter.typeError( 5320_error, clause.location(), SecondarySourceLocation{}.append("The first clause is here:", lowLevelClause->location()), "This try statement already has a low-level catch clause." ); lowLevelClause = &clause; if (clause.parameters() && !clause.parameters()->parameters().empty()) { if ( clause.parameters()->parameters().size() != 1 || *clause.parameters()->parameters().front()->type() != *TypeProvider::bytesMemory() ) m_errorReporter.typeError(6231_error, clause.location(), "Expected `catch (bytes memory ...) { ... }` or `catch { ... }`."); if (!m_evmVersion.supportsReturndata()) m_errorReporter.typeError( 9908_error, clause.location(), "This catch clause type cannot be used on the selected EVM version (" + m_evmVersion.name() + "). You need at least a Byzantium-compatible EVM or use `catch { ... }`." ); } } else if (clause.errorName() == "Error") { if (!m_evmVersion.supportsReturndata()) m_errorReporter.typeError( 1812_error, clause.location(), "This catch clause type cannot be used on the selected EVM version (" + m_evmVersion.name() + "). You need at least a Byzantium-compatible EVM or use `catch { ... }`." ); if (errorClause) m_errorReporter.typeError( 1036_error, clause.location(), SecondarySourceLocation{}.append("The first clause is here:", errorClause->location()), "This try statement already has an \"Error\" catch clause." ); errorClause = &clause; if ( !clause.parameters() || clause.parameters()->parameters().size() != 1 || *clause.parameters()->parameters().front()->type() != *TypeProvider::stringMemory() ) m_errorReporter.typeError(2943_error, clause.location(), "Expected `catch Error(string memory ...) { ... }`."); } else m_errorReporter.typeError( 3542_error, clause.location(), "Invalid catch clause name. Expected either `catch (...)` or `catch Error(...)`." ); } } bool TypeChecker::visit(WhileStatement const& _whileStatement) { expectType(_whileStatement.condition(), *TypeProvider::boolean()); _whileStatement.body().accept(*this); return false; } bool TypeChecker::visit(ForStatement const& _forStatement) { if (_forStatement.initializationExpression()) _forStatement.initializationExpression()->accept(*this); if (_forStatement.condition()) expectType(*_forStatement.condition(), *TypeProvider::boolean()); if (_forStatement.loopExpression()) _forStatement.loopExpression()->accept(*this); _forStatement.body().accept(*this); return false; } void TypeChecker::endVisit(Return const& _return) { ParameterList const* params = _return.annotation().functionReturnParameters; if (!_return.expression()) { if (params && !params->parameters().empty()) m_errorReporter.typeError(6777_error, _return.location(), "Return arguments required."); return; } if (!params) { m_errorReporter.typeError(7552_error, _return.location(), "Return arguments not allowed."); return; } TypePointers returnTypes; for (auto const& var: params->parameters()) returnTypes.push_back(type(*var)); if (auto tupleType = dynamic_cast(type(*_return.expression()))) { if (tupleType->components().size() != params->parameters().size()) m_errorReporter.typeError(5132_error, _return.location(), "Different number of arguments in return statement than in returns declaration."); else { BoolResult result = tupleType->isImplicitlyConvertibleTo(TupleType(returnTypes)); if (!result) m_errorReporter.typeErrorConcatenateDescriptions( 5992_error, _return.expression()->location(), "Return argument type " + type(*_return.expression())->toString() + " is not implicitly convertible to expected type " + TupleType(returnTypes).toString(false) + ".", result.message() ); } } else if (params->parameters().size() != 1) m_errorReporter.typeError(8863_error, _return.location(), "Different number of arguments in return statement than in returns declaration."); else { TypePointer const& expected = type(*params->parameters().front()); BoolResult result = type(*_return.expression())->isImplicitlyConvertibleTo(*expected); if (!result) m_errorReporter.typeErrorConcatenateDescriptions( 6359_error, _return.expression()->location(), "Return argument type " + type(*_return.expression())->toString() + " is not implicitly convertible to expected type (type of first return variable) " + expected->toString() + ".", result.message() ); } } void TypeChecker::endVisit(EmitStatement const& _emit) { if ( *_emit.eventCall().annotation().kind != FunctionCallKind::FunctionCall || type(_emit.eventCall().expression())->category() != Type::Category::Function || dynamic_cast(*type(_emit.eventCall().expression())).kind() != FunctionType::Kind::Event ) m_errorReporter.typeError(9292_error, _emit.eventCall().expression().location(), "Expression has to be an event invocation."); } bool TypeChecker::visit(VariableDeclarationStatement const& _statement) { if (!_statement.initialValue()) { // No initial value is only permitted for single variables with specified type. // This usually already results in a parser error. if (_statement.declarations().size() != 1 || !_statement.declarations().front()) { solAssert(m_errorReporter.hasErrors(), ""); // It is okay to return here, as there are no named components on the // left-hand-side that could cause any damage later. return false; } VariableDeclaration const& varDecl = *_statement.declarations().front(); solAssert(varDecl.annotation().type, ""); if (dynamic_cast(type(varDecl))) m_errorReporter.typeError( 4182_error, varDecl.location(), "Uninitialized mapping. Mappings cannot be created dynamically, you have to assign them from a state variable." ); varDecl.accept(*this); return false; } // Here we have an initial value and might have to derive some types before we can visit // the variable declaration(s). _statement.initialValue()->accept(*this); TypePointers valueTypes; if (auto tupleType = dynamic_cast(type(*_statement.initialValue()))) valueTypes = tupleType->components(); else valueTypes = TypePointers{type(*_statement.initialValue())}; vector> const& variables = _statement.declarations(); if (variables.empty()) // We already have an error for this in the SyntaxChecker. solAssert(m_errorReporter.hasErrors(), ""); else if (valueTypes.size() != variables.size()) m_errorReporter.typeError( 7364_error, _statement.location(), "Different number of components on the left hand side (" + toString(variables.size()) + ") than on the right hand side (" + toString(valueTypes.size()) + ")." ); for (size_t i = 0; i < min(variables.size(), valueTypes.size()); ++i) { if (!variables[i]) continue; VariableDeclaration const& var = *variables[i]; solAssert(!var.value(), "Value has to be tied to statement."); TypePointer const& valueComponentType = valueTypes[i]; solAssert(!!valueComponentType, ""); solAssert(var.annotation().type, ""); var.accept(*this); BoolResult result = valueComponentType->isImplicitlyConvertibleTo(*var.annotation().type); if (!result) { auto errorMsg = "Type " + valueComponentType->toString() + " is not implicitly convertible to expected type " + var.annotation().type->toString(); if ( valueComponentType->category() == Type::Category::RationalNumber && dynamic_cast(*valueComponentType).isFractional() && valueComponentType->mobileType() ) { if (var.annotation().type->operator==(*valueComponentType->mobileType())) m_errorReporter.typeError( 5107_error, _statement.location(), errorMsg + ", but it can be explicitly converted." ); else m_errorReporter.typeError( 4486_error, _statement.location(), errorMsg + ". Try converting to type " + valueComponentType->mobileType()->toString() + " or use an explicit conversion." ); } else m_errorReporter.typeErrorConcatenateDescriptions( 9574_error, _statement.location(), errorMsg + ".", result.message() ); } } if (valueTypes.size() != variables.size()) { solAssert(m_errorReporter.hasErrors(), "Should have errors!"); for (auto const& var: variables) if (var && !var->annotation().type) BOOST_THROW_EXCEPTION(FatalError()); } return false; } void TypeChecker::endVisit(ExpressionStatement const& _statement) { if (type(_statement.expression())->category() == Type::Category::RationalNumber) if (!dynamic_cast(*type(_statement.expression())).mobileType()) m_errorReporter.typeError(3757_error, _statement.expression().location(), "Invalid rational number."); if (auto call = dynamic_cast(&_statement.expression())) { if (auto callType = dynamic_cast(type(call->expression()))) { auto kind = callType->kind(); if ( kind == FunctionType::Kind::BareCall || kind == FunctionType::Kind::BareCallCode || kind == FunctionType::Kind::BareDelegateCall || kind == FunctionType::Kind::BareStaticCall ) m_errorReporter.warning(9302_error, _statement.location(), "Return value of low-level calls not used."); else if (kind == FunctionType::Kind::Send) m_errorReporter.warning(5878_error, _statement.location(), "Failure condition of 'send' ignored. Consider using 'transfer' instead."); } } } bool TypeChecker::visit(Conditional const& _conditional) { expectType(_conditional.condition(), *TypeProvider::boolean()); _conditional.trueExpression().accept(*this); _conditional.falseExpression().accept(*this); TypePointer trueType = type(_conditional.trueExpression())->mobileType(); TypePointer falseType = type(_conditional.falseExpression())->mobileType(); TypePointer commonType = nullptr; if (!trueType) m_errorReporter.typeError(9717_error, _conditional.trueExpression().location(), "Invalid mobile type in true expression."); else commonType = trueType; if (!falseType) m_errorReporter.typeError(3703_error, _conditional.falseExpression().location(), "Invalid mobile type in false expression."); else commonType = falseType; if (!trueType && !falseType) BOOST_THROW_EXCEPTION(FatalError()); else if (trueType && falseType) { commonType = Type::commonType(trueType, falseType); if (!commonType) { m_errorReporter.typeError( 1080_error, _conditional.location(), "True expression's type " + trueType->toString() + " does not match false expression's type " + falseType->toString() + "." ); // even we can't find a common type, we have to set a type here, // otherwise the upper statement will not be able to check the type. commonType = trueType; } } _conditional.annotation().isConstant = false; _conditional.annotation().type = commonType; _conditional.annotation().isPure = *_conditional.condition().annotation().isPure && *_conditional.trueExpression().annotation().isPure && *_conditional.falseExpression().annotation().isPure; _conditional.annotation().isLValue = false; if (_conditional.annotation().willBeWrittenTo) m_errorReporter.typeError( 2212_error, _conditional.location(), "Conditional expression as left value is not supported yet." ); return false; } void TypeChecker::checkExpressionAssignment(Type const& _type, Expression const& _expression) { if (auto const* tupleExpression = dynamic_cast(&_expression)) { if (tupleExpression->components().empty()) m_errorReporter.typeError(5547_error, _expression.location(), "Empty tuple on the left hand side."); auto const* tupleType = dynamic_cast(&_type); auto const& types = tupleType && tupleExpression->components().size() != 1 ? tupleType->components() : vector { &_type }; solAssert( tupleExpression->components().size() == types.size() || m_errorReporter.hasErrors(), "Array sizes don't match and no errors generated." ); for (size_t i = 0; i < min(tupleExpression->components().size(), types.size()); i++) if (types[i]) { solAssert(!!tupleExpression->components()[i], ""); checkExpressionAssignment(*types[i], *tupleExpression->components()[i]); } } else if (_type.nameable() && _type.containsNestedMapping()) { bool isLocalOrReturn = false; if (auto const* identifier = dynamic_cast(&_expression)) if (auto const *variableDeclaration = dynamic_cast(identifier->annotation().referencedDeclaration)) if (variableDeclaration->isLocalOrReturn()) isLocalOrReturn = true; if (!isLocalOrReturn) m_errorReporter.typeError(9214_error, _expression.location(), "Types in storage containing (nested) mappings cannot be assigned to."); } } bool TypeChecker::visit(Assignment const& _assignment) { requireLValue( _assignment.leftHandSide(), _assignment.assignmentOperator() == Token::Assign ); TypePointer t = type(_assignment.leftHandSide()); _assignment.annotation().type = t; _assignment.annotation().isPure = false; _assignment.annotation().isLValue = false; _assignment.annotation().isConstant = false; checkExpressionAssignment(*t, _assignment.leftHandSide()); if (TupleType const* tupleType = dynamic_cast(t)) { if (_assignment.assignmentOperator() != Token::Assign) m_errorReporter.typeError( 4289_error, _assignment.location(), "Compound assignment is not allowed for tuple types." ); // Sequenced assignments of tuples is not valid, make the result a "void" type. _assignment.annotation().type = TypeProvider::emptyTuple(); expectType(_assignment.rightHandSide(), *tupleType); // expectType does not cause fatal errors, so we have to check again here. if (dynamic_cast(type(_assignment.rightHandSide()))) checkDoubleStorageAssignment(_assignment); } else if (_assignment.assignmentOperator() == Token::Assign) expectType(_assignment.rightHandSide(), *t); else { // compound assignment _assignment.rightHandSide().accept(*this); TypePointer resultType = t->binaryOperatorResult( TokenTraits::AssignmentToBinaryOp(_assignment.assignmentOperator()), type(_assignment.rightHandSide()) ); if (!resultType || *resultType != *t) m_errorReporter.typeError( 7366_error, _assignment.location(), "Operator " + string(TokenTraits::toString(_assignment.assignmentOperator())) + " not compatible with types " + t->toString() + " and " + type(_assignment.rightHandSide())->toString() ); } return false; } bool TypeChecker::visit(TupleExpression const& _tuple) { _tuple.annotation().isConstant = false; vector> const& components = _tuple.components(); TypePointers types; if (_tuple.annotation().willBeWrittenTo) { if (_tuple.isInlineArray()) m_errorReporter.fatalTypeError(3025_error, _tuple.location(), "Inline array type cannot be declared as LValue."); for (auto const& component: components) if (component) { requireLValue( *component, _tuple.annotation().lValueOfOrdinaryAssignment ); types.push_back(type(*component)); } else types.push_back(TypePointer()); if (components.size() == 1) _tuple.annotation().type = type(*components[0]); else _tuple.annotation().type = TypeProvider::tuple(move(types)); // If some of the components are not LValues, the error is reported above. _tuple.annotation().isLValue = true; _tuple.annotation().isPure = false; } else { bool isPure = true; TypePointer inlineArrayType = nullptr; for (size_t i = 0; i < components.size(); ++i) { if (!components[i]) m_errorReporter.fatalTypeError(8381_error, _tuple.location(), "Tuple component cannot be empty."); components[i]->accept(*this); types.push_back(type(*components[i])); if (types[i]->category() == Type::Category::Tuple) if (dynamic_cast(*types[i]).components().empty()) { if (_tuple.isInlineArray()) m_errorReporter.fatalTypeError(5604_error, components[i]->location(), "Array component cannot be empty."); m_errorReporter.typeError(6473_error, components[i]->location(), "Tuple component cannot be empty."); } // Note: code generation will visit each of the expression even if they are not assigned from. if (types[i]->category() == Type::Category::RationalNumber && components.size() > 1) if (!dynamic_cast(*types[i]).mobileType()) m_errorReporter.fatalTypeError(3390_error, components[i]->location(), "Invalid rational number."); if (_tuple.isInlineArray()) { solAssert(!!types[i], "Inline array cannot have empty components"); if ((i == 0 || inlineArrayType) && !types[i]->mobileType()) m_errorReporter.fatalTypeError(9563_error, components[i]->location(), "Invalid mobile type."); if (i == 0) inlineArrayType = types[i]->mobileType(); else if (inlineArrayType) inlineArrayType = Type::commonType(inlineArrayType, types[i]); } if (!*components[i]->annotation().isPure) isPure = false; } _tuple.annotation().isPure = isPure; if (_tuple.isInlineArray()) { if (!inlineArrayType) m_errorReporter.fatalTypeError(6378_error, _tuple.location(), "Unable to deduce common type for array elements."); else if (!inlineArrayType->nameable()) m_errorReporter.fatalTypeError( 9656_error, _tuple.location(), "Unable to deduce nameable type for array elements. Try adding explicit type conversion for the first element." ); else if (inlineArrayType->containsNestedMapping()) m_errorReporter.fatalTypeError( 1545_error, _tuple.location(), "Type " + inlineArrayType->toString(true) + " is only valid in storage." ); _tuple.annotation().type = TypeProvider::array(DataLocation::Memory, inlineArrayType, types.size()); } else { if (components.size() == 1) _tuple.annotation().type = type(*components[0]); else _tuple.annotation().type = TypeProvider::tuple(move(types)); } _tuple.annotation().isLValue = false; } return false; } bool TypeChecker::visit(UnaryOperation const& _operation) { // Inc, Dec, Add, Sub, Not, BitNot, Delete Token op = _operation.getOperator(); bool const modifying = (op == Token::Inc || op == Token::Dec || op == Token::Delete); if (modifying) requireLValue(_operation.subExpression(), false); else _operation.subExpression().accept(*this); TypePointer const& subExprType = type(_operation.subExpression()); TypePointer t = type(_operation.subExpression())->unaryOperatorResult(op); if (!t) { string description = "Unary operator " + string(TokenTraits::toString(op)) + " cannot be applied to type " + subExprType->toString(); if (modifying) // Cannot just report the error, ignore the unary operator, and continue, // because the sub-expression was already processed with requireLValue() m_errorReporter.fatalTypeError(9767_error, _operation.location(), description); else m_errorReporter.typeError(4907_error, _operation.location(), description); t = subExprType; } _operation.annotation().type = t; _operation.annotation().isConstant = false; _operation.annotation().isPure = !modifying && *_operation.subExpression().annotation().isPure; _operation.annotation().isLValue = false; return false; } void TypeChecker::endVisit(BinaryOperation const& _operation) { TypePointer const& leftType = type(_operation.leftExpression()); TypePointer const& rightType = type(_operation.rightExpression()); TypeResult result = leftType->binaryOperatorResult(_operation.getOperator(), rightType); TypePointer commonType = result.get(); if (!commonType) { m_errorReporter.typeError( 2271_error, _operation.location(), "Operator " + string(TokenTraits::toString(_operation.getOperator())) + " not compatible with types " + leftType->toString() + " and " + rightType->toString() + (!result.message().empty() ? ". " + result.message() : "") ); commonType = leftType; } _operation.annotation().commonType = commonType; _operation.annotation().type = TokenTraits::isCompareOp(_operation.getOperator()) ? TypeProvider::boolean() : commonType; _operation.annotation().isPure = *_operation.leftExpression().annotation().isPure && *_operation.rightExpression().annotation().isPure; _operation.annotation().isLValue = false; _operation.annotation().isConstant = false; if (_operation.getOperator() == Token::Exp || _operation.getOperator() == Token::SHL) { string operation = _operation.getOperator() == Token::Exp ? "exponentiation" : "shift"; if ( leftType->category() == Type::Category::RationalNumber && rightType->category() != Type::Category::RationalNumber ) if (( commonType->category() == Type::Category::Integer && dynamic_cast(*commonType).numBits() != 256 ) || ( commonType->category() == Type::Category::FixedPoint && dynamic_cast(*commonType).numBits() != 256 )) m_errorReporter.warning( 9085_error, _operation.location(), "Result of " + operation + " has type " + commonType->toString() + " and thus " "might overflow. Silence this warning by converting the literal to the " "expected type." ); if ( commonType->category() == Type::Category::Integer && rightType->category() == Type::Category::Integer && dynamic_cast(*commonType).numBits() < dynamic_cast(*rightType).numBits() ) m_errorReporter.warning( 3149_error, _operation.location(), "The result type of the " + operation + " operation is equal to the type of the first operand (" + commonType->toString() + ") ignoring the (larger) type of the second operand (" + rightType->toString() + ") which might be unexpected. Silence this warning by either converting " "the first or the second operand to the type of the other." ); } } TypePointer TypeChecker::typeCheckTypeConversionAndRetrieveReturnType( FunctionCall const& _functionCall ) { solAssert(*_functionCall.annotation().kind == FunctionCallKind::TypeConversion, ""); TypePointer const& expressionType = type(_functionCall.expression()); vector> const& arguments = _functionCall.arguments(); bool const isPositionalCall = _functionCall.names().empty(); TypePointer resultType = dynamic_cast(*expressionType).actualType(); if (arguments.size() != 1) m_errorReporter.typeError( 2558_error, _functionCall.location(), "Exactly one argument expected for explicit type conversion." ); else if (!isPositionalCall) m_errorReporter.typeError( 5153_error, _functionCall.location(), "Type conversion cannot allow named arguments." ); else { Type 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(argType)) dataLoc = argRefType->location(); if (auto type = dynamic_cast(resultType)) resultType = TypeProvider::withLocation(type, dataLoc, type->isPointer()); BoolResult result = argType->isExplicitlyConvertibleTo(*resultType); if (result) { if (auto argArrayType = dynamic_cast(argType)) { auto resultArrayType = dynamic_cast(resultType); solAssert(!!resultArrayType, ""); solAssert( argArrayType->location() != DataLocation::Storage || ( ( resultArrayType->isPointer() || (argArrayType->isByteArray() && resultArrayType->isByteArray()) ) && resultArrayType->location() == DataLocation::Storage ), "Invalid explicit conversion to storage type." ); } } else { if ( resultType->category() == Type::Category::Contract && argType->category() == Type::Category::Address ) { solAssert(dynamic_cast(resultType)->isPayable(), ""); solAssert( dynamic_cast(argType)->stateMutability() < StateMutability::Payable, "" ); SecondarySourceLocation ssl; if ( auto const* identifier = dynamic_cast(arguments.front().get()) ) if ( auto const* variableDeclaration = dynamic_cast( identifier->annotation().referencedDeclaration ) ) ssl.append( "Did you mean to declare this variable as \"address payable\"?", variableDeclaration->location() ); m_errorReporter.typeError( 7398_error, _functionCall.location(), ssl, "Explicit type conversion not allowed from non-payable \"address\" to \"" + resultType->toString() + "\", which has a payable fallback function." ); } else if ( auto const* functionType = dynamic_cast(argType); functionType && functionType->kind() == FunctionType::Kind::External && resultType->category() == Type::Category::Address ) m_errorReporter.typeError( 5030_error, _functionCall.location(), "Explicit type conversion not allowed from \"" + argType->toString() + "\" to \"" + resultType->toString() + "\". To obtain the address of the contract of the function, " + "you can use the .address member of the function." ); else m_errorReporter.typeErrorConcatenateDescriptions( 9640_error, _functionCall.location(), "Explicit type conversion not allowed from \"" + argType->toString() + "\" to \"" + resultType->toString() + "\".", result.message() ); } if (auto addressType = dynamic_cast(resultType)) if (addressType->stateMutability() != StateMutability::Payable) { bool payable = false; if (argType->category() != Type::Category::Address) payable = argType->isExplicitlyConvertibleTo(*TypeProvider::payableAddress()); resultType = payable ? TypeProvider::payableAddress() : TypeProvider::address(); } } return resultType; } void TypeChecker::typeCheckFunctionCall( FunctionCall const& _functionCall, FunctionTypePointer _functionType ) { // Actual function call or struct constructor call. solAssert(!!_functionType, ""); solAssert(_functionType->kind() != FunctionType::Kind::ABIDecode, ""); if (_functionType->kind() == FunctionType::Kind::Declaration) { solAssert(_functionType->declaration().annotation().contract, ""); if ( m_currentContract && m_currentContract->derivesFrom(*_functionType->declaration().annotation().contract) && !dynamic_cast(_functionType->declaration()).isImplemented() ) m_errorReporter.typeError( 7501_error, _functionCall.location(), "Cannot call unimplemented base function." ); else m_errorReporter.typeError( 3419_error, _functionCall.location(), "Cannot call function via contract type name." ); return; } // Check for unsupported use of bare static call if ( _functionType->kind() == FunctionType::Kind::BareStaticCall && !m_evmVersion.hasStaticCall() ) m_errorReporter.typeError( 5052_error, _functionCall.location(), "\"staticcall\" is not supported by the VM version." ); // Perform standard function call type checking typeCheckFunctionGeneralChecks(_functionCall, _functionType); } void TypeChecker::typeCheckFallbackFunction(FunctionDefinition const& _function) { solAssert(_function.isFallback(), ""); if (_function.libraryFunction()) m_errorReporter.typeError(5982_error, _function.location(), "Libraries cannot have fallback functions."); if (_function.stateMutability() != StateMutability::NonPayable && _function.stateMutability() != StateMutability::Payable) m_errorReporter.typeError( 4575_error, _function.location(), "Fallback function must be payable or non-payable, but is \"" + stateMutabilityToString(_function.stateMutability()) + "\"." ); if (_function.visibility() != Visibility::External) m_errorReporter.typeError(1159_error, _function.location(), "Fallback function must be defined as \"external\"."); if (!_function.returnParameters().empty()) { if (_function.returnParameters().size() > 1 || *type(*_function.returnParameters().front()) != *TypeProvider::bytesMemory()) m_errorReporter.typeError(5570_error, _function.returnParameterList()->location(), "Fallback function can only have a single \"bytes memory\" return value."); else m_errorReporter.typeError(6151_error, _function.returnParameterList()->location(), "Return values for fallback functions are not yet implemented."); } if (!_function.parameters().empty()) m_errorReporter.typeError(3978_error, _function.parameterList().location(), "Fallback function cannot take parameters."); } void TypeChecker::typeCheckReceiveFunction(FunctionDefinition const& _function) { solAssert(_function.isReceive(), ""); if (_function.libraryFunction()) m_errorReporter.typeError(4549_error, _function.location(), "Libraries cannot have receive ether functions."); if (_function.stateMutability() != StateMutability::Payable) m_errorReporter.typeError( 7793_error, _function.location(), "Receive ether function must be payable, but is \"" + stateMutabilityToString(_function.stateMutability()) + "\"." ); if (_function.visibility() != Visibility::External) m_errorReporter.typeError(4095_error, _function.location(), "Receive ether function must be defined as \"external\"."); if (!_function.returnParameters().empty()) m_errorReporter.typeError(6899_error, _function.returnParameterList()->location(), "Receive ether function cannot return values."); if (!_function.parameters().empty()) m_errorReporter.typeError(6857_error, _function.parameterList().location(), "Receive ether function cannot take parameters."); } void TypeChecker::typeCheckConstructor(FunctionDefinition const& _function) { solAssert(_function.isConstructor(), ""); if (_function.overrides()) m_errorReporter.typeError(1209_error, _function.location(), "Constructors cannot override."); if (!_function.returnParameters().empty()) m_errorReporter.typeError(9712_error, _function.returnParameterList()->location(), "Non-empty \"returns\" directive for constructor."); if (_function.stateMutability() != StateMutability::NonPayable && _function.stateMutability() != StateMutability::Payable) m_errorReporter.typeError( 1558_error, _function.location(), "Constructor must be payable or non-payable, but is \"" + stateMutabilityToString(_function.stateMutability()) + "\"." ); if (!_function.noVisibilitySpecified()) { auto const& contract = dynamic_cast(*_function.scope()); if (_function.visibility() != Visibility::Public && _function.visibility() != Visibility::Internal) m_errorReporter.typeError(9239_error, _function.location(), "Constructor cannot have visibility."); else if (_function.isPublic() && contract.abstract()) m_errorReporter.declarationError( 8295_error, _function.location(), "Abstract contracts cannot have public constructors. Remove the \"public\" keyword to fix this." ); else if (!_function.isPublic() && !contract.abstract()) m_errorReporter.declarationError( 1845_error, _function.location(), "Non-abstract contracts cannot have internal constructors. Remove the \"internal\" keyword and make the contract abstract to fix this." ); else m_errorReporter.warning( 2462_error, _function.location(), "Visibility for constructor is ignored. If you want the contract to be non-deployable, making it \"abstract\" is sufficient." ); } } void TypeChecker::typeCheckABIEncodeFunctions( FunctionCall const& _functionCall, FunctionTypePointer _functionType ) { solAssert(!!_functionType, ""); solAssert( _functionType->kind() == FunctionType::Kind::ABIEncode || _functionType->kind() == FunctionType::Kind::ABIEncodePacked || _functionType->kind() == FunctionType::Kind::ABIEncodeWithSelector || _functionType->kind() == FunctionType::Kind::ABIEncodeWithSignature, "ABI function has unexpected FunctionType::Kind." ); solAssert(_functionType->takesArbitraryParameters(), "ABI functions should be variadic."); bool const isPacked = _functionType->kind() == FunctionType::Kind::ABIEncodePacked; solAssert(_functionType->padArguments() != isPacked, "ABI function with unexpected padding"); bool const abiEncoderV2 = experimentalFeatureActive(ExperimentalFeature::ABIEncoderV2); // Check for named arguments if (!_functionCall.names().empty()) { m_errorReporter.typeError( 2627_error, _functionCall.location(), "Named arguments cannot be used for functions that take arbitrary parameters." ); return; } // Perform standard function call type checking typeCheckFunctionGeneralChecks(_functionCall, _functionType); // Check additional arguments for variadic functions vector> const& arguments = _functionCall.arguments(); for (size_t i = 0; i < arguments.size(); ++i) { auto const& argType = type(*arguments[i]); if (argType->category() == Type::Category::RationalNumber) { auto const& rationalType = dynamic_cast(*argType); if (rationalType.isFractional()) { m_errorReporter.typeError( 6090_error, arguments[i]->location(), "Fractional numbers cannot yet be encoded." ); continue; } else if (!argType->mobileType()) { m_errorReporter.typeError( 8009_error, arguments[i]->location(), "Invalid rational number (too large or division by zero)." ); continue; } else if (isPacked) { m_errorReporter.typeError( 7279_error, arguments[i]->location(), "Cannot perform packed encoding for a literal." " Please convert it to an explicit type first." ); continue; } } if (isPacked && !typeSupportedByOldABIEncoder(*argType, false /* isLibrary */)) { m_errorReporter.typeError( 9578_error, arguments[i]->location(), "Type not supported in packed mode." ); continue; } if (!argType->fullEncodingType(false, abiEncoderV2, !_functionType->padArguments())) m_errorReporter.typeError( 2056_error, arguments[i]->location(), "This type cannot be encoded." ); } } void TypeChecker::typeCheckFunctionGeneralChecks( FunctionCall const& _functionCall, FunctionTypePointer _functionType ) { // Actual function call or struct constructor call. solAssert(!!_functionType, ""); solAssert(_functionType->kind() != FunctionType::Kind::ABIDecode, ""); bool const isPositionalCall = _functionCall.names().empty(); bool const isVariadic = _functionType->takesArbitraryParameters(); auto functionCallKind = *_functionCall.annotation().kind; solAssert( !isVariadic || functionCallKind == FunctionCallKind::FunctionCall, "Struct constructor calls cannot be variadic." ); TypePointers const& parameterTypes = _functionType->parameterTypes(); vector> const& arguments = _functionCall.arguments(); vector> const& argumentNames = _functionCall.names(); // Check number of passed in arguments if ( arguments.size() < parameterTypes.size() || (!isVariadic && arguments.size() > parameterTypes.size()) ) { bool const isStructConstructorCall = functionCallKind == FunctionCallKind::StructConstructorCall; auto [errorId, description] = [&]() -> tuple { string msg = isVariadic ? "Need at least " + toString(parameterTypes.size()) + " arguments for " + string(isStructConstructorCall ? "struct constructor" : "function call") + ", but provided only " + toString(arguments.size()) + "." : "Wrong argument count for " + string(isStructConstructorCall ? "struct constructor" : "function call") + ": " + toString(arguments.size()) + " arguments given but " + string(isVariadic ? "need at least " : "expected ") + toString(parameterTypes.size()) + "."; if (isStructConstructorCall) return { isVariadic ? 1123_error : 9755_error, msg }; else if ( _functionType->kind() == FunctionType::Kind::BareCall || _functionType->kind() == FunctionType::Kind::BareCallCode || _functionType->kind() == FunctionType::Kind::BareDelegateCall || _functionType->kind() == FunctionType::Kind::BareStaticCall ) { if (arguments.empty()) return { isVariadic ? 7653_error : 6138_error, msg + " This function requires a single bytes argument." " Use \"\" as argument to provide empty calldata." }; else return { isVariadic ? 9390_error : 8922_error, 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 ( _functionType->kind() == FunctionType::Kind::KECCAK256 || _functionType->kind() == FunctionType::Kind::SHA256 || _functionType->kind() == FunctionType::Kind::RIPEMD160 ) return { isVariadic ? 1220_error : 4323_error, msg + " This function requires a single bytes argument." " Use abi.encodePacked(...) to obtain the pre-0.5.0" " behaviour or abi.encode(...) to use ABI encoding." }; else return { isVariadic ? 9308_error : 6160_error, msg }; }(); m_errorReporter.typeError(errorId, _functionCall.location(), description); return; } // Parameter to argument map std::vector paramArgMap(parameterTypes.size()); // Map parameters to arguments - trivially for positional calls, less so for named calls if (isPositionalCall) for (size_t i = 0; i < paramArgMap.size(); ++i) paramArgMap[i] = arguments[i].get(); else { auto const& parameterNames = _functionType->parameterNames(); solAssert( parameterNames.size() == argumentNames.size(), "Unexpected parameter length mismatch!" ); // Check for duplicate argument names { bool duplication = false; for (size_t i = 0; i < argumentNames.size(); i++) for (size_t j = i + 1; j < argumentNames.size(); j++) if (*argumentNames[i] == *argumentNames[j]) { duplication = true; m_errorReporter.typeError( 6995_error, arguments[i]->location(), "Duplicate named argument \"" + *argumentNames[i] + "\"." ); } if (duplication) return; } // map parameter names to argument names { bool not_all_mapped = false; for (size_t i = 0; i < argumentNames.size(); i++) { size_t j; for (j = 0; j < parameterNames.size(); j++) if (parameterNames[j] == *argumentNames[i]) break; if (j < parameterNames.size()) paramArgMap[j] = arguments[i].get(); else { not_all_mapped = true; m_errorReporter.typeError( 4974_error, _functionCall.location(), "Named argument \"" + *argumentNames[i] + "\" does not match function declaration." ); } } if (not_all_mapped) return; } } // Check for compatible types between arguments and parameters for (size_t i = 0; i < paramArgMap.size(); ++i) { solAssert(!!paramArgMap[i], "unmapped parameter"); if (!type(*paramArgMap[i])->isImplicitlyConvertibleTo(*parameterTypes[i])) { auto [errorId, description] = [&]() -> tuple { string msg = "Invalid type for argument in function call. " "Invalid implicit conversion from " + type(*paramArgMap[i])->toString() + " to " + parameterTypes[i]->toString() + " requested."; if ( _functionType->kind() == FunctionType::Kind::BareCall || _functionType->kind() == FunctionType::Kind::BareCallCode || _functionType->kind() == FunctionType::Kind::BareDelegateCall || _functionType->kind() == FunctionType::Kind::BareStaticCall ) return { 8051_error, 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 ( _functionType->kind() == FunctionType::Kind::KECCAK256 || _functionType->kind() == FunctionType::Kind::SHA256 || _functionType->kind() == FunctionType::Kind::RIPEMD160 ) return { 7556_error, msg + " This function requires a single bytes argument." " Use abi.encodePacked(...) to obtain the pre-0.5.0" " behaviour or abi.encode(...) to use ABI encoding." }; else return { 9553_error, msg }; }(); m_errorReporter.typeError(errorId, paramArgMap[i]->location(), description); } } TypePointers const& returnParameterTypes = _functionType->returnParameterTypes(); bool isLibraryCall = (_functionType->kind() == FunctionType::Kind::DelegateCall); bool callRequiresABIEncoding = // ABIEncode/ABIDecode calls not included because they should have been already validated // at this point and they have variadic arguments so they need special handling. _functionType->kind() == FunctionType::Kind::DelegateCall || _functionType->kind() == FunctionType::Kind::External || _functionType->kind() == FunctionType::Kind::Creation || _functionType->kind() == FunctionType::Kind::Event; if (callRequiresABIEncoding && !experimentalFeatureActive(ExperimentalFeature::ABIEncoderV2)) { solAssert(!isVariadic, ""); solAssert(parameterTypes.size() == arguments.size(), ""); solAssert(!_functionType->isBareCall(), ""); solAssert(*_functionCall.annotation().kind == FunctionCallKind::FunctionCall, ""); for (size_t i = 0; i < parameterTypes.size(); ++i) { solAssert(parameterTypes[i], ""); if (!typeSupportedByOldABIEncoder(*parameterTypes[i], isLibraryCall)) m_errorReporter.typeError( 2443_error, paramArgMap[i]->location(), "The type of this parameter, " + parameterTypes[i]->toString(true) + ", " "is only supported in ABIEncoderV2. " "Use \"pragma experimental ABIEncoderV2;\" to enable the feature." ); } for (size_t i = 0; i < returnParameterTypes.size(); ++i) { solAssert(returnParameterTypes[i], ""); if (!typeSupportedByOldABIEncoder(*returnParameterTypes[i], isLibraryCall)) m_errorReporter.typeError( 2428_error, _functionCall.location(), "The type of return parameter " + toString(i + 1) + ", " + returnParameterTypes[i]->toString(true) + ", " "is only supported in ABIEncoderV2. " "Use \"pragma experimental ABIEncoderV2;\" to enable the feature." ); } } } bool TypeChecker::visit(FunctionCall const& _functionCall) { vector> const& arguments = _functionCall.arguments(); bool argumentsArePure = true; // We need to check arguments' type first as they will be needed for overload resolution. for (ASTPointer const& argument: arguments) { argument->accept(*this); if (!*argument->annotation().isPure) argumentsArePure = false; } // Store argument types - and names if given - for overload resolution { FuncCallArguments funcCallArgs; funcCallArgs.names = _functionCall.names(); for (ASTPointer const& argument: arguments) funcCallArgs.types.push_back(type(*argument)); _functionCall.expression().annotation().arguments = std::move(funcCallArgs); } _functionCall.expression().accept(*this); Type const* expressionType = type(_functionCall.expression()); // Determine function call kind and function type for this FunctionCall node FunctionCallAnnotation& funcCallAnno = _functionCall.annotation(); FunctionTypePointer functionType = nullptr; funcCallAnno.isConstant = false; bool isLValue = false; // Determine and assign function call kind, lvalue, purity and function type for this FunctionCall node switch (expressionType->category()) { case Type::Category::Function: functionType = dynamic_cast(expressionType); funcCallAnno.kind = FunctionCallKind::FunctionCall; // Purity for function calls also depends upon the callee and its FunctionType funcCallAnno.isPure = argumentsArePure && *_functionCall.expression().annotation().isPure && functionType && functionType->isPure(); if ( functionType->kind() == FunctionType::Kind::ArrayPush || functionType->kind() == FunctionType::Kind::ByteArrayPush ) isLValue = functionType->parameterTypes().empty(); break; case Type::Category::TypeType: { // Determine type for type conversion or struct construction expressions TypePointer const& actualType = dynamic_cast(*expressionType).actualType(); solAssert(!!actualType, ""); if (actualType->category() == Type::Category::Struct) { if (actualType->containsNestedMapping()) m_errorReporter.fatalTypeError( 9515_error, _functionCall.location(), "Struct containing a (nested) mapping cannot be constructed." ); functionType = dynamic_cast(*actualType).constructorType(); funcCallAnno.kind = FunctionCallKind::StructConstructorCall; } else funcCallAnno.kind = FunctionCallKind::TypeConversion; funcCallAnno.isPure = argumentsArePure; break; } default: m_errorReporter.fatalTypeError(5704_error, _functionCall.location(), "Type is not callable"); // Unreachable, because fatalTypeError throws. We don't set kind, but that's okay because the switch below // is never reached. And, even if it was, SetOnce would trigger an assertion violation and not UB. funcCallAnno.isPure = argumentsArePure; break; } funcCallAnno.isLValue = isLValue; // Determine return types switch (*funcCallAnno.kind) { case FunctionCallKind::TypeConversion: funcCallAnno.type = typeCheckTypeConversionAndRetrieveReturnType(_functionCall); break; case FunctionCallKind::StructConstructorCall: // fall-through case FunctionCallKind::FunctionCall: { TypePointers returnTypes; switch (functionType->kind()) { case FunctionType::Kind::ABIDecode: { returnTypes = typeCheckABIDecodeAndRetrieveReturnType( _functionCall, experimentalFeatureActive(ExperimentalFeature::ABIEncoderV2) ); break; } case FunctionType::Kind::ABIEncode: case FunctionType::Kind::ABIEncodePacked: case FunctionType::Kind::ABIEncodeWithSelector: case FunctionType::Kind::ABIEncodeWithSignature: { typeCheckABIEncodeFunctions(_functionCall, functionType); returnTypes = functionType->returnParameterTypes(); break; } case FunctionType::Kind::MetaType: returnTypes = typeCheckMetaTypeFunctionAndRetrieveReturnType(_functionCall); break; default: { typeCheckFunctionCall(_functionCall, functionType); returnTypes = m_evmVersion.supportsReturndata() ? functionType->returnParameterTypes() : functionType->returnParameterTypesWithoutDynamicTypes(); break; } } funcCallAnno.type = returnTypes.size() == 1 ? move(returnTypes.front()) : TypeProvider::tuple(move(returnTypes)); break; } default: // for non-callables, ensure error reported and annotate node to void function solAssert(m_errorReporter.hasErrors(), ""); funcCallAnno.kind = FunctionCallKind::FunctionCall; funcCallAnno.type = TypeProvider::emptyTuple(); break; } return false; } bool TypeChecker::visit(FunctionCallOptions const& _functionCallOptions) { solAssert(_functionCallOptions.options().size() == _functionCallOptions.names().size(), "Lengths of name & value arrays differ!"); _functionCallOptions.expression().annotation().arguments = _functionCallOptions.annotation().arguments; _functionCallOptions.expression().accept(*this); _functionCallOptions.annotation().isPure = false; _functionCallOptions.annotation().isConstant = false; _functionCallOptions.annotation().isLValue = false; auto expressionFunctionType = dynamic_cast(type(_functionCallOptions.expression())); if (!expressionFunctionType) { m_errorReporter.fatalTypeError(2622_error, _functionCallOptions.location(), "Expected callable expression before call options."); return false; } bool setSalt = false; bool setValue = false; bool setGas = false; FunctionType::Kind kind = expressionFunctionType->kind(); if ( kind != FunctionType::Kind::Creation && kind != FunctionType::Kind::External && kind != FunctionType::Kind::BareCall && kind != FunctionType::Kind::BareCallCode && kind != FunctionType::Kind::BareDelegateCall && kind != FunctionType::Kind::BareStaticCall ) { m_errorReporter.fatalTypeError( 2193_error, _functionCallOptions.location(), "Function call options can only be set on external function calls or contract creations." ); return false; } auto setCheckOption = [&](bool& _option, string const&& _name, bool _alreadySet = false) { if (_option || _alreadySet) m_errorReporter.typeError( 9886_error, _functionCallOptions.location(), _alreadySet ? "Option \"" + std::move(_name) + "\" has already been set." : "Duplicate option \"" + std::move(_name) + "\"." ); _option = true; }; for (size_t i = 0; i < _functionCallOptions.names().size(); ++i) { string const& name = *(_functionCallOptions.names()[i]); if (name == "salt") { if (kind == FunctionType::Kind::Creation) { setCheckOption(setSalt, "salt", expressionFunctionType->saltSet()); expectType(*_functionCallOptions.options()[i], *TypeProvider::fixedBytes(32)); } else m_errorReporter.typeError( 2721_error, _functionCallOptions.location(), "Function call option \"salt\" can only be used with \"new\"." ); } else if (name == "value") { if (kind == FunctionType::Kind::BareDelegateCall) m_errorReporter.typeError( 6189_error, _functionCallOptions.location(), "Cannot set option \"value\" for delegatecall." ); else if (kind == FunctionType::Kind::BareStaticCall) m_errorReporter.typeError( 2842_error, _functionCallOptions.location(), "Cannot set option \"value\" for staticcall." ); else if (!expressionFunctionType->isPayable()) m_errorReporter.typeError( 7006_error, _functionCallOptions.location(), kind == FunctionType::Kind::Creation ? "Cannot set option \"value\", since the constructor of " + expressionFunctionType->returnParameterTypes().front()->toString() + " is not payable." : "Cannot set option \"value\" on a non-payable function type." ); else { expectType(*_functionCallOptions.options()[i], *TypeProvider::uint256()); setCheckOption(setValue, "value", expressionFunctionType->valueSet()); } } else if (name == "gas") { if (kind == FunctionType::Kind::Creation) m_errorReporter.typeError( 9903_error, _functionCallOptions.location(), "Function call option \"gas\" cannot be used with \"new\"." ); else { expectType(*_functionCallOptions.options()[i], *TypeProvider::uint256()); setCheckOption(setGas, "gas", expressionFunctionType->gasSet()); } } else m_errorReporter.typeError( 9318_error, _functionCallOptions.location(), "Unknown call option \"" + name + "\". Valid options are \"salt\", \"value\" and \"gas\"." ); } if (setSalt && !m_evmVersion.hasCreate2()) m_errorReporter.typeError( 5189_error, _functionCallOptions.location(), "Unsupported call option \"salt\" (requires Constantinople-compatible VMs)." ); _functionCallOptions.annotation().type = expressionFunctionType->copyAndSetCallOptions(setGas, setValue, setSalt); return false; } void TypeChecker::endVisit(NewExpression const& _newExpression) { TypePointer type = _newExpression.typeName().annotation().type; solAssert(!!type, "Type name not resolved."); _newExpression.annotation().isConstant = false; _newExpression.annotation().isLValue = false; if (auto contractName = dynamic_cast(&_newExpression.typeName())) { auto contract = dynamic_cast(&dereference(*contractName)); if (!contract) m_errorReporter.fatalTypeError(5540_error, _newExpression.location(), "Identifier is not a contract."); if (contract->isInterface()) m_errorReporter.fatalTypeError(2971_error, _newExpression.location(), "Cannot instantiate an interface."); if (contract->abstract()) m_errorReporter.typeError(4614_error, _newExpression.location(), "Cannot instantiate an abstract 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); _newExpression.annotation().isPure = false; } else if (type->category() == Type::Category::Array) { if (type->containsNestedMapping()) m_errorReporter.fatalTypeError( 1164_error, _newExpression.typeName().location(), "Array containing a (nested) mapping cannot be constructed in memory." ); if (!type->isDynamicallySized()) m_errorReporter.typeError( 3904_error, _newExpression.typeName().location(), "Length has to be placed in parentheses after the array type for new expression." ); type = TypeProvider::withLocationIfReference(DataLocation::Memory, type); _newExpression.annotation().type = TypeProvider::function( TypePointers{TypeProvider::uint256()}, TypePointers{type}, strings(1, ""), strings(1, ""), FunctionType::Kind::ObjectCreation, false, StateMutability::Pure ); _newExpression.annotation().isPure = true; } else { _newExpression.annotation().isPure = false; m_errorReporter.fatalTypeError(8807_error, _newExpression.location(), "Contract or array type expected."); } } bool TypeChecker::visit(MemberAccess const& _memberAccess) { _memberAccess.expression().accept(*this); TypePointer exprType = type(_memberAccess.expression()); ASTString const& memberName = _memberAccess.memberName(); auto& annotation = _memberAccess.annotation(); // Retrieve the types of the arguments if this is used to call a function. auto const& arguments = annotation.arguments; MemberList::MemberMap possibleMembers = exprType->members(currentDefinitionScope()).membersByName(memberName); size_t const initialMemberCount = possibleMembers.size(); if (initialMemberCount > 1 && arguments) { // do overload resolution for (auto it = possibleMembers.begin(); it != possibleMembers.end();) if ( it->type->category() == Type::Category::Function && !dynamic_cast(*it->type).canTakeArguments(*arguments, exprType) ) it = possibleMembers.erase(it); else ++it; } annotation.isConstant = false; if (possibleMembers.empty()) { if (initialMemberCount == 0 && !dynamic_cast(exprType)) { // Try to see if the member was removed because it is only available for storage types. auto storageType = TypeProvider::withLocationIfReference( DataLocation::Storage, exprType ); if (!storageType->members(currentDefinitionScope()).membersByName(memberName).empty()) m_errorReporter.fatalTypeError( 4994_error, _memberAccess.location(), "Member \"" + memberName + "\" is not available in " + exprType->toString() + " outside of storage." ); } auto [errorId, description] = [&]() -> tuple { string errorMsg = "Member \"" + memberName + "\" not found or not visible " "after argument-dependent lookup in " + exprType->toString() + "."; if (auto const* funType = dynamic_cast(exprType)) { TypePointers const& t = funType->returnParameterTypes(); if (memberName == "value") { if (funType->kind() == FunctionType::Kind::Creation) return { 8827_error, "Constructor for " + t.front()->toString() + " must be payable for member \"value\" to be available." }; else if ( funType->kind() == FunctionType::Kind::DelegateCall || funType->kind() == FunctionType::Kind::BareDelegateCall ) return { 8477_error, "Member \"value\" is not allowed in delegated calls due to \"msg.value\" persisting." }; else return { 8820_error, "Member \"value\" is only available for payable functions." }; } else if ( t.size() == 1 && ( t.front()->category() == Type::Category::Struct || t.front()->category() == Type::Category::Contract ) ) return { 6005_error, errorMsg + " Did you intend to call the function?" }; } else if (exprType->category() == Type::Category::Contract) { for (MemberList::Member const& addressMember: TypeProvider::payableAddress()->nativeMembers(nullptr)) if (addressMember.name == memberName) { auto const* var = dynamic_cast(&_memberAccess.expression()); string varName = var ? var->name() : "..."; errorMsg += " Use \"address(" + varName + ")." + memberName + "\" to access this address member."; return { 3125_error, errorMsg }; } } else if (auto const* addressType = dynamic_cast(exprType)) { // Trigger error when using send or transfer with a non-payable fallback function. if (memberName == "send" || memberName == "transfer") { solAssert( addressType->stateMutability() != StateMutability::Payable, "Expected address not-payable as members were not found" ); return { 9862_error, "\"send\" and \"transfer\" are only available for objects of type \"address payable\", not \"" + exprType->toString() + "\"." }; } } return { 9582_error, errorMsg }; }(); m_errorReporter.fatalTypeError( errorId, _memberAccess.location(), description ); } else if (possibleMembers.size() > 1) m_errorReporter.fatalTypeError( 6675_error, _memberAccess.location(), "Member \"" + memberName + "\" not unique " "after argument-dependent lookup in " + exprType->toString() + (memberName == "value" ? " - did you forget the \"payable\" modifier?" : ".") ); annotation.referencedDeclaration = possibleMembers.front().declaration; annotation.type = possibleMembers.front().type; VirtualLookup requiredLookup = VirtualLookup::Static; if (auto funType = dynamic_cast(annotation.type)) { solAssert( !funType->bound() || exprType->isImplicitlyConvertibleTo(*funType->selfType()), "Function \"" + memberName + "\" cannot be called on an object of type " + exprType->toString() + " (expected " + funType->selfType()->toString() + ")." ); if ( dynamic_cast(exprType) && !annotation.referencedDeclaration && (memberName == "value" || memberName == "gas") ) m_errorReporter.typeError( 1621_error, _memberAccess.location(), "Using \"." + memberName + "(...)\" is deprecated. Use \"{" + memberName + ": ...}\" instead." ); if ( funType->kind() == FunctionType::Kind::ArrayPush && arguments.value().numArguments() != 0 && exprType->containsNestedMapping() ) m_errorReporter.typeError( 8871_error, _memberAccess.location(), "Storage arrays with nested mappings do not support .push()." ); if (!funType->bound()) if (auto contractType = dynamic_cast(exprType)) requiredLookup = contractType->isSuper() ? VirtualLookup::Super : VirtualLookup::Virtual; } annotation.requiredLookup = requiredLookup; if (auto const* structType = dynamic_cast(exprType)) annotation.isLValue = !structType->dataStoredIn(DataLocation::CallData); else if (exprType->category() == Type::Category::Array) annotation.isLValue = false; else if (exprType->category() == Type::Category::FixedBytes) annotation.isLValue = false; else if (TypeType const* typeType = dynamic_cast(exprType)) { if (ContractType const* contractType = dynamic_cast(typeType->actualType())) { annotation.isLValue = annotation.referencedDeclaration->isLValue(); if ( auto const* functionType = dynamic_cast(annotation.type); functionType && functionType->kind() == FunctionType::Kind::Declaration ) annotation.isPure = *_memberAccess.expression().annotation().isPure; } else annotation.isLValue = false; } else if (exprType->category() == Type::Category::Module) { annotation.isPure = *_memberAccess.expression().annotation().isPure; annotation.isLValue = false; } else annotation.isLValue = false; // TODO some members might be pure, but for example `address(0x123).balance` is not pure // although every subexpression is, so leaving this limited for now. if (auto tt = dynamic_cast(exprType)) if (tt->actualType()->category() == Type::Category::Enum) annotation.isPure = true; if ( auto const* functionType = dynamic_cast(exprType); functionType && functionType->hasDeclaration() && dynamic_cast(&functionType->declaration()) && memberName == "selector" ) if (auto const* parentAccess = dynamic_cast(&_memberAccess.expression())) { bool isPure = *parentAccess->expression().annotation().isPure; if (auto const* exprInt = dynamic_cast(&parentAccess->expression())) if (exprInt->name() == "this" || exprInt->name() == "super") isPure = true; annotation.isPure = isPure; } if (auto magicType = dynamic_cast(exprType)) { if (magicType->kind() == MagicType::Kind::ABI) annotation.isPure = true; else if (magicType->kind() == MagicType::Kind::MetaType && ( memberName == "creationCode" || memberName == "runtimeCode" )) { annotation.isPure = true; ContractType const& accessedContractType = dynamic_cast(*magicType->typeArgument()); if ( memberName == "runtimeCode" && !accessedContractType.immutableVariables().empty() ) m_errorReporter.typeError( 9274_error, _memberAccess.location(), "\"runtimeCode\" is not available for contracts containing immutable variables." ); 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; else if (magicType->kind() == MagicType::Kind::MetaType && memberName == "interfaceId") annotation.isPure = true; else if ( magicType->kind() == MagicType::Kind::MetaType && (memberName == "min" || memberName == "max") ) annotation.isPure = true; } if (!annotation.isPure.set()) annotation.isPure = false; return false; } bool TypeChecker::visit(IndexAccess const& _access) { _access.annotation().isConstant = false; _access.baseExpression().accept(*this); TypePointer baseType = type(_access.baseExpression()); TypePointer resultType = nullptr; bool isLValue = false; bool isPure = *_access.baseExpression().annotation().isPure; Expression const* index = _access.indexExpression(); switch (baseType->category()) { case Type::Category::ArraySlice: { auto const& arrayType = dynamic_cast(*baseType).arrayType(); if (arrayType.location() != DataLocation::CallData || !arrayType.isDynamicallySized()) m_errorReporter.typeError(4802_error, _access.location(), "Index access is only implemented for slices of dynamic calldata arrays."); baseType = &arrayType; [[fallthrough]]; } case Type::Category::Array: { ArrayType const& actualType = dynamic_cast(*baseType); if (!index) m_errorReporter.typeError(9689_error, _access.location(), "Index expression cannot be omitted."); else if (actualType.isString()) { m_errorReporter.typeError(9961_error, _access.location(), "Index access for string is not possible."); index->accept(*this); } else { expectType(*index, *TypeProvider::uint256()); if (!m_errorReporter.hasErrors()) if (auto numberType = dynamic_cast(type(*index))) { solAssert(!numberType->isFractional(), ""); if (!actualType.isDynamicallySized() && actualType.length() <= numberType->literalValue(nullptr)) m_errorReporter.typeError(3383_error, _access.location(), "Out of bounds array access."); } } resultType = actualType.baseType(); isLValue = actualType.location() != DataLocation::CallData; break; } case Type::Category::Mapping: { MappingType const& actualType = dynamic_cast(*baseType); if (!index) m_errorReporter.typeError(1267_error, _access.location(), "Index expression cannot be omitted."); else expectType(*index, *actualType.keyType()); resultType = actualType.valueType(); isLValue = true; break; } case Type::Category::TypeType: { TypeType const& typeType = dynamic_cast(*baseType); if (dynamic_cast(typeType.actualType())) m_errorReporter.typeError(2876_error, _access.location(), "Index access for contracts or libraries is not possible."); if (!index) resultType = TypeProvider::typeType(TypeProvider::array(DataLocation::Memory, typeType.actualType())); else { u256 length = 1; if (expectType(*index, *TypeProvider::uint256())) { if (auto indexValue = dynamic_cast(type(*index))) length = indexValue->literalValue(nullptr); else m_errorReporter.fatalTypeError(3940_error, index->location(), "Integer constant expected."); } else solAssert(m_errorReporter.hasErrors(), "Expected errors as expectType returned false"); resultType = TypeProvider::typeType(TypeProvider::array( DataLocation::Memory, typeType.actualType(), length )); } break; } case Type::Category::FixedBytes: { FixedBytesType const& bytesType = dynamic_cast(*baseType); if (!index) m_errorReporter.typeError(8830_error, _access.location(), "Index expression cannot be omitted."); else { if (!expectType(*index, *TypeProvider::uint256())) m_errorReporter.fatalTypeError(6318_error, _access.location(), "Index expression cannot be represented as an unsigned integer."); if (auto integerType = dynamic_cast(type(*index))) if (bytesType.numBytes() <= integerType->literalValue(nullptr)) m_errorReporter.typeError(1859_error, _access.location(), "Out of bounds array access."); } resultType = TypeProvider::fixedBytes(1); isLValue = false; // @todo this heavily depends on how it is embedded break; } default: m_errorReporter.fatalTypeError( 2614_error, _access.baseExpression().location(), "Indexed expression has to be a type, mapping or array (is " + baseType->toString() + ")" ); } _access.annotation().type = resultType; _access.annotation().isLValue = isLValue; if (index && !*index->annotation().isPure) isPure = false; _access.annotation().isPure = isPure; return false; } bool TypeChecker::visit(IndexRangeAccess const& _access) { _access.annotation().isConstant = false; _access.baseExpression().accept(*this); bool isLValue = false; // TODO: set this correctly when implementing slices for memory and storage arrays bool isPure = *_access.baseExpression().annotation().isPure; if (Expression const* start = _access.startExpression()) { expectType(*start, *TypeProvider::uint256()); if (!*start->annotation().isPure) isPure = false; } if (Expression const* end = _access.endExpression()) { expectType(*end, *TypeProvider::uint256()); if (!*end->annotation().isPure) isPure = false; } _access.annotation().isLValue = isLValue; _access.annotation().isPure = isPure; TypePointer exprType = type(_access.baseExpression()); if (exprType->category() == Type::Category::TypeType) { m_errorReporter.typeError(1760_error, _access.location(), "Types cannot be sliced."); _access.annotation().type = exprType; return false; } ArrayType const* arrayType = nullptr; if (auto const* arraySlice = dynamic_cast(exprType)) arrayType = &arraySlice->arrayType(); else if (!(arrayType = dynamic_cast(exprType))) m_errorReporter.fatalTypeError(4781_error, _access.location(), "Index range access is only possible for arrays and array slices."); if (arrayType->location() != DataLocation::CallData || !arrayType->isDynamicallySized()) m_errorReporter.typeError(1227_error, _access.location(), "Index range access is only supported for dynamic calldata arrays."); else if (arrayType->baseType()->isDynamicallyEncoded()) m_errorReporter.typeError(2148_error, _access.location(), "Index range access is not supported for arrays with dynamically encoded base types."); _access.annotation().type = TypeProvider::arraySlice(*arrayType); return false; } vector TypeChecker::cleanOverloadedDeclarations( Identifier const& _identifier, vector const& _candidates ) { solAssert(_candidates.size() > 1, ""); vector uniqueDeclarations; for (Declaration const* declaration: _candidates) { solAssert(declaration, ""); // the declaration is functionDefinition, eventDefinition or a VariableDeclaration while declarations > 1 solAssert( dynamic_cast(declaration) || dynamic_cast(declaration) || dynamic_cast(declaration) || dynamic_cast(declaration), "Found overloading involving something not a function, event or a (magic) variable." ); FunctionTypePointer functionType {declaration->functionType(false)}; if (!functionType) functionType = declaration->functionType(true); solAssert(functionType, "Failed to determine the function type of the overloaded."); for (TypePointer parameter: functionType->parameterTypes() + functionType->returnParameterTypes()) if (!parameter) m_errorReporter.fatalDeclarationError(3893_error, _identifier.location(), "Function type can not be used in this context."); if (uniqueDeclarations.end() == find_if( uniqueDeclarations.begin(), uniqueDeclarations.end(), [&](Declaration const* d) { FunctionType const* newFunctionType = d->functionType(false); if (!newFunctionType) newFunctionType = d->functionType(true); return newFunctionType && functionType->hasEqualParameterTypes(*newFunctionType); } )) uniqueDeclarations.push_back(declaration); } return uniqueDeclarations; } bool TypeChecker::visit(Identifier const& _identifier) { IdentifierAnnotation& annotation = _identifier.annotation(); if (!annotation.referencedDeclaration) { annotation.overloadedDeclarations = cleanOverloadedDeclarations(_identifier, annotation.candidateDeclarations); if (annotation.overloadedDeclarations.empty()) m_errorReporter.fatalTypeError(7593_error, _identifier.location(), "No candidates for overload resolution found."); else if (annotation.overloadedDeclarations.size() == 1) annotation.referencedDeclaration = *annotation.overloadedDeclarations.begin(); else if (!annotation.arguments) { // The identifier should be a public state variable shadowing other functions vector candidates; for (Declaration const* declaration: annotation.overloadedDeclarations) { if (VariableDeclaration const* variableDeclaration = dynamic_cast(declaration)) candidates.push_back(declaration); } if (candidates.empty()) m_errorReporter.fatalTypeError(2144_error, _identifier.location(), "No matching declaration found after variable lookup."); else if (candidates.size() == 1) annotation.referencedDeclaration = candidates.front(); else m_errorReporter.fatalTypeError(7589_error, _identifier.location(), "No unique declaration found after variable lookup."); } else { vector candidates; for (Declaration const* declaration: annotation.overloadedDeclarations) { FunctionTypePointer functionType = declaration->functionType(true); solAssert(!!functionType, "Requested type not present."); if (functionType->canTakeArguments(*annotation.arguments)) candidates.push_back(declaration); } if (candidates.size() == 1) annotation.referencedDeclaration = candidates.front(); else { SecondarySourceLocation ssl; for (Declaration const* declaration: annotation.overloadedDeclarations) if (!declaration->location().isValid()) { // Try to re-construct function definition string description; for (auto const& param: declaration->functionType(true)->parameterTypes()) description += (description.empty() ? "" : ", ") + param->toString(false); description = "function " + _identifier.name() + "(" + description + ")"; ssl.append("Candidate: " + description, declaration->location()); } else ssl.append("Candidate:", declaration->location()); if (candidates.empty()) m_errorReporter.fatalTypeError(9322_error, _identifier.location(), ssl, "No matching declaration found after argument-dependent lookup."); else m_errorReporter.fatalTypeError(4487_error, _identifier.location(), ssl, "No unique declaration found after argument-dependent lookup."); } } } solAssert( !!annotation.referencedDeclaration, "Referenced declaration is null after overload resolution." ); bool isConstant = false; annotation.isLValue = annotation.referencedDeclaration->isLValue(); annotation.type = annotation.referencedDeclaration->type(); solAssert(annotation.type, "Declaration referenced before type could be determined."); if (auto variableDeclaration = dynamic_cast(annotation.referencedDeclaration)) annotation.isPure = isConstant = variableDeclaration->isConstant(); else if (dynamic_cast(annotation.referencedDeclaration)) annotation.isPure = dynamic_cast(annotation.type); else if (dynamic_cast(annotation.type)) annotation.isPure = true; else if (dynamic_cast(annotation.type)) annotation.isPure = true; else annotation.isPure = false; annotation.isConstant = isConstant; annotation.requiredLookup = dynamic_cast(annotation.referencedDeclaration) ? VirtualLookup::Virtual : VirtualLookup::Static; // Check for deprecated function names. // The check is done here for the case without an actual function call. if (FunctionType const* fType = dynamic_cast(_identifier.annotation().type)) { if (_identifier.name() == "sha3" && fType->kind() == FunctionType::Kind::KECCAK256) m_errorReporter.typeError( 3557_error, _identifier.location(), "\"sha3\" has been deprecated in favour of \"keccak256\"." ); else if (_identifier.name() == "suicide" && fType->kind() == FunctionType::Kind::Selfdestruct) m_errorReporter.typeError( 8050_error, _identifier.location(), "\"suicide\" has been deprecated in favour of \"selfdestruct\"." ); } if ( MagicVariableDeclaration const* magicVar = dynamic_cast(annotation.referencedDeclaration) ) if (magicVar->type()->category() == Type::Category::Integer) { solAssert(_identifier.name() == "now", ""); m_errorReporter.typeError( 7359_error, _identifier.location(), "\"now\" has been deprecated. Use \"block.timestamp\" instead." ); } return false; } void TypeChecker::endVisit(ElementaryTypeNameExpression const& _expr) { _expr.annotation().type = TypeProvider::typeType(TypeProvider::fromElementaryTypeName(_expr.type().typeName(), _expr.type().stateMutability())); _expr.annotation().isPure = true; _expr.annotation().isLValue = false; _expr.annotation().isConstant = false; } void TypeChecker::endVisit(Literal const& _literal) { if (_literal.looksLikeAddress()) { // Assign type here if it even looks like an address. This prevents double errors for invalid addresses _literal.annotation().type = TypeProvider::payableAddress(); string msg; if (_literal.valueWithoutUnderscores().length() != 42) // "0x" + 40 hex digits // looksLikeAddress enforces that it is a hex literal starting with "0x" msg = "This looks like an address but is not exactly 40 hex digits. It is " + to_string(_literal.valueWithoutUnderscores().length() - 2) + " hex digits."; else if (!_literal.passesAddressChecksum()) { msg = "This looks like an address but has an invalid checksum."; if (!_literal.getChecksummedAddress().empty()) msg += " Correct checksummed address: \"" + _literal.getChecksummedAddress() + "\"."; } if (!msg.empty()) m_errorReporter.syntaxError( 9429_error, _literal.location(), msg + " If this is not used as an address, please prepend '00'. " + "For more information please see https://solidity.readthedocs.io/en/develop/types.html#address-literals" ); } if (_literal.isHexNumber() && _literal.subDenomination() != Literal::SubDenomination::None) m_errorReporter.fatalTypeError( 5145_error, _literal.location(), "Hexadecimal numbers cannot be used with unit denominations. " "You can use an expression of the form \"0x1234 * 1 day\" instead." ); if (_literal.subDenomination() == Literal::SubDenomination::Year) m_errorReporter.typeError( 4820_error, _literal.location(), "Using \"years\" as a unit denomination is deprecated." ); if (!_literal.annotation().type) _literal.annotation().type = TypeProvider::forLiteral(_literal); if (!_literal.annotation().type) m_errorReporter.fatalTypeError(2826_error, _literal.location(), "Invalid literal value."); _literal.annotation().isPure = true; _literal.annotation().isLValue = false; _literal.annotation().isConstant = false; } void TypeChecker::endVisit(UsingForDirective const& _usingFor) { if (m_currentContract->isInterface()) m_errorReporter.typeError( 9088_error, _usingFor.location(), "The \"using for\" directive is not allowed inside interfaces." ); } bool TypeChecker::contractDependenciesAreCyclic( ContractDefinition const& _contract, std::set const& _seenContracts ) const { // Naive depth-first search that remembers nodes already seen. if (_seenContracts.count(&_contract)) return true; set seen(_seenContracts); seen.insert(&_contract); for (auto const* c: _contract.annotation().contractDependencies) if (contractDependenciesAreCyclic(*c, seen)) return true; return false; } Declaration const& TypeChecker::dereference(Identifier const& _identifier) const { solAssert(!!_identifier.annotation().referencedDeclaration, "Declaration not stored."); return *_identifier.annotation().referencedDeclaration; } Declaration const& TypeChecker::dereference(UserDefinedTypeName const& _typeName) const { solAssert(!!_typeName.annotation().referencedDeclaration, "Declaration not stored."); return *_typeName.annotation().referencedDeclaration; } bool TypeChecker::expectType(Expression const& _expression, Type const& _expectedType) { _expression.accept(*this); BoolResult result = type(_expression)->isImplicitlyConvertibleTo(_expectedType); if (!result) { auto errorMsg = "Type " + type(_expression)->toString() + " is not implicitly convertible to expected type " + _expectedType.toString(); if ( type(_expression)->category() == Type::Category::RationalNumber && dynamic_cast(type(_expression))->isFractional() && type(_expression)->mobileType() ) { if (_expectedType.operator==(*type(_expression)->mobileType())) m_errorReporter.typeError( 4426_error, _expression.location(), errorMsg + ", but it can be explicitly converted." ); else m_errorReporter.typeErrorConcatenateDescriptions( 2326_error, _expression.location(), errorMsg + ". Try converting to type " + type(_expression)->mobileType()->toString() + " or use an explicit conversion.", result.message() ); } else m_errorReporter.typeErrorConcatenateDescriptions( 7407_error, _expression.location(), errorMsg + ".", result.message() ); return false; } return true; } void TypeChecker::requireLValue(Expression const& _expression, bool _ordinaryAssignment) { _expression.annotation().willBeWrittenTo = true; _expression.annotation().lValueOfOrdinaryAssignment = _ordinaryAssignment; _expression.accept(*this); if (*_expression.annotation().isLValue) return; auto [errorId, description] = [&]() -> tuple { if (*_expression.annotation().isConstant) return { 6520_error, "Cannot assign to a constant variable." }; if (auto indexAccess = dynamic_cast(&_expression)) { if (type(indexAccess->baseExpression())->category() == Type::Category::FixedBytes) return { 4360_error, "Single bytes in fixed bytes arrays cannot be modified." }; else if (auto arrayType = dynamic_cast(type(indexAccess->baseExpression()))) if (arrayType->dataStoredIn(DataLocation::CallData)) return { 6182_error, "Calldata arrays are read-only." }; } if (auto memberAccess = dynamic_cast(&_expression)) { if (auto structType = dynamic_cast(type(memberAccess->expression()))) { if (structType->dataStoredIn(DataLocation::CallData)) return { 4156_error, "Calldata structs are read-only." }; } else if (dynamic_cast(type(memberAccess->expression()))) if (memberAccess->memberName() == "length") return { 7567_error, "Member \"length\" is read-only and cannot be used to resize arrays." }; } if (auto identifier = dynamic_cast(&_expression)) if (auto varDecl = dynamic_cast(identifier->annotation().referencedDeclaration)) if (varDecl->isExternalCallableParameter() && dynamic_cast(identifier->annotation().type)) return { 7128_error, "External function arguments of reference type are read-only." }; return { 4247_error, "Expression has to be an lvalue." }; }(); m_errorReporter.typeError(errorId, _expression.location(), description); } bool TypeChecker::experimentalFeatureActive(ExperimentalFeature _feature) const { solAssert(m_currentSourceUnit, ""); if (m_currentContract) solAssert(m_currentSourceUnit == &m_currentContract->sourceUnit(), ""); return m_currentSourceUnit->annotation().experimentalFeatures.count(_feature); }