solidity/libsolidity/analysis/TypeChecker.cpp

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/*
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 <http://www.gnu.org/licenses/>.
*/
/**
* @author Christian <c@ethdev.com>
* @date 2015
* Type analyzer and checker.
*/
#include <libsolidity/analysis/TypeChecker.h>
#include <memory>
#include <boost/algorithm/cxx11/all_of.hpp>
#include <boost/algorithm/string/predicate.hpp>
#include <boost/algorithm/string/join.hpp>
#include <boost/range/adaptor/reversed.hpp>
#include <libsolidity/ast/AST.h>
#include <libsolidity/inlineasm/AsmAnalysis.h>
#include <libsolidity/inlineasm/AsmAnalysisInfo.h>
#include <libsolidity/inlineasm/AsmData.h>
#include <libsolidity/interface/ErrorReporter.h>
#include <libdevcore/Algorithms.h>
using namespace std;
using namespace dev;
using namespace dev::solidity;
namespace
{
bool typeSupportedByOldABIEncoder(Type const& _type)
{
if (_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<ArrayType const&>(_type);
auto base = arrayType.baseType();
if (!typeSupportedByOldABIEncoder(*base) || (base->category() == Type::Category::Array && base->isDynamicallySized()))
return false;
}
return true;
}
}
bool TypeChecker::checkTypeRequirements(ASTNode const& _contract)
{
_contract.accept(*this);
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_scope = &_contract;
// We force our own visiting order here. The structs have to be excluded below.
set<ASTNode const*> visited;
for (auto const& s: _contract.definedStructs())
visited.insert(s);
ASTNode::listAccept(_contract.definedStructs(), *this);
ASTNode::listAccept(_contract.baseContracts(), *this);
checkContractDuplicateFunctions(_contract);
checkContractDuplicateEvents(_contract);
checkContractIllegalOverrides(_contract);
checkContractAbstractFunctions(_contract);
checkContractBaseConstructorArguments(_contract);
FunctionDefinition const* function = _contract.constructor();
if (function)
{
if (!function->returnParameters().empty())
m_errorReporter.typeError(function->returnParameterList()->location(), "Non-empty \"returns\" directive for constructor.");
if (function->stateMutability() != StateMutability::NonPayable && function->stateMutability() != StateMutability::Payable)
m_errorReporter.typeError(
function->location(),
"Constructor must be payable or non-payable, but is \"" +
stateMutabilityToString(function->stateMutability()) +
"\"."
);
if (function->visibility() != FunctionDefinition::Visibility::Public && function->visibility() != FunctionDefinition::Visibility::Internal)
m_errorReporter.typeError(function->location(), "Constructor must be public or internal.");
}
for (FunctionDefinition const* function: _contract.definedFunctions())
if (function->isFallback())
{
if (_contract.isLibrary())
m_errorReporter.typeError(function->location(), "Libraries cannot have fallback functions.");
if (function->stateMutability() != StateMutability::NonPayable && function->stateMutability() != StateMutability::Payable)
m_errorReporter.typeError(
function->location(),
"Fallback function must be payable or non-payable, but is \"" +
stateMutabilityToString(function->stateMutability()) +
"\"."
);
if (!function->parameters().empty())
m_errorReporter.typeError(function->parameterList().location(), "Fallback function cannot take parameters.");
if (!function->returnParameters().empty())
m_errorReporter.typeError(function->returnParameterList()->location(), "Fallback function cannot return values.");
if (function->visibility() != FunctionDefinition::Visibility::External)
m_errorReporter.typeError(function->location(), "Fallback function must be defined as \"external\".");
}
for (auto const& n: _contract.subNodes())
if (!visited.count(n.get()))
n->accept(*this);
checkContractExternalTypeClashes(_contract);
// check for hash collisions in function signatures
set<FixedHash<4>> hashes;
for (auto const& it: _contract.interfaceFunctionList())
{
FixedHash<4> const& hash = it.first;
if (hashes.count(hash))
m_errorReporter.typeError(
_contract.location(),
string("Function signature hash collision for ") + it.second->externalSignature()
);
hashes.insert(hash);
}
if (_contract.isLibrary())
checkLibraryRequirements(_contract);
return false;
}
void TypeChecker::checkContractDuplicateFunctions(ContractDefinition const& _contract)
{
/// Checks that two functions with the same name defined in this contract have different
/// argument types and that there is at most one constructor.
map<string, vector<FunctionDefinition const*>> functions;
FunctionDefinition const* constructor = nullptr;
FunctionDefinition const* fallback = nullptr;
for (FunctionDefinition const* function: _contract.definedFunctions())
if (function->isConstructor())
{
if (constructor)
m_errorReporter.declarationError(
function->location(),
SecondarySourceLocation().append("Another declaration is here:", constructor->location()),
"More than one constructor defined."
);
constructor = function;
}
else if (function->isFallback())
{
if (fallback)
m_errorReporter.declarationError(
function->location(),
SecondarySourceLocation().append("Another declaration is here:", fallback->location()),
"Only one fallback function is allowed."
);
fallback = function;
}
else
{
solAssert(!function->name().empty(), "");
functions[function->name()].push_back(function);
}
findDuplicateDefinitions(functions, "Function with same name and arguments defined twice.");
}
void TypeChecker::checkContractDuplicateEvents(ContractDefinition const& _contract)
{
/// Checks that two events with the same name defined in this contract have different
/// argument types
map<string, vector<EventDefinition const*>> events;
for (EventDefinition const* event: _contract.events())
events[event->name()].push_back(event);
findDuplicateDefinitions(events, "Event with same name and arguments defined twice.");
}
template <class T>
void TypeChecker::findDuplicateDefinitions(map<string, vector<T>> const& _definitions, string _message)
{
for (auto const& it: _definitions)
{
vector<T> const& overloads = it.second;
set<size_t> reported;
for (size_t i = 0; i < overloads.size() && !reported.count(i); ++i)
{
SecondarySourceLocation ssl;
for (size_t j = i + 1; j < overloads.size(); ++j)
if (FunctionType(*overloads[i]).hasEqualParameterTypes(FunctionType(*overloads[j])))
{
ssl.append("Other declaration is here:", overloads[j]->location());
reported.insert(j);
}
if (ssl.infos.size() > 0)
{
ssl.limitSize(_message);
m_errorReporter.declarationError(
overloads[i]->location(),
ssl,
_message
);
}
}
}
}
void TypeChecker::checkContractAbstractFunctions(ContractDefinition const& _contract)
{
// Mapping from name to function definition (exactly one per argument type equality class) and
// flag to indicate whether it is fully implemented.
using FunTypeAndFlag = std::pair<FunctionTypePointer, bool>;
map<string, vector<FunTypeAndFlag>> functions;
// Search from base to derived
for (ContractDefinition const* contract: boost::adaptors::reverse(_contract.annotation().linearizedBaseContracts))
for (FunctionDefinition const* function: contract->definedFunctions())
{
// Take constructors out of overload hierarchy
if (function->isConstructor())
continue;
auto& overloads = functions[function->name()];
FunctionTypePointer funType = make_shared<FunctionType>(*function);
auto it = find_if(overloads.begin(), overloads.end(), [&](FunTypeAndFlag const& _funAndFlag)
{
return funType->hasEqualParameterTypes(*_funAndFlag.first);
});
if (it == overloads.end())
overloads.push_back(make_pair(funType, function->isImplemented()));
else if (it->second)
{
if (!function->isImplemented())
m_errorReporter.typeError(function->location(), "Redeclaring an already implemented function as abstract");
}
else if (function->isImplemented())
it->second = true;
}
// Set to not fully implemented if at least one flag is false.
for (auto const& it: functions)
for (auto const& funAndFlag: it.second)
if (!funAndFlag.second)
{
FunctionDefinition const* function = dynamic_cast<FunctionDefinition const*>(&funAndFlag.first->declaration());
solAssert(function, "");
_contract.annotation().unimplementedFunctions.push_back(function);
break;
}
}
void TypeChecker::checkContractBaseConstructorArguments(ContractDefinition const& _contract)
{
vector<ContractDefinition const*> const& bases = _contract.annotation().linearizedBaseContracts;
// Determine the arguments that are used for the base constructors.
for (ContractDefinition const* contract: bases)
{
if (FunctionDefinition const* constructor = contract->constructor())
for (auto const& modifier: constructor->modifiers())
if (auto baseContract = dynamic_cast<ContractDefinition const*>(&dereference(*modifier->name())))
{
if (modifier->arguments())
{
if (baseContract->constructor())
annotateBaseConstructorArguments(_contract, baseContract->constructor(), modifier.get());
}
else
m_errorReporter.declarationError(
modifier->location(),
"Modifier-style base constructor call without arguments."
);
}
for (ASTPointer<InheritanceSpecifier> const& base: contract->baseContracts())
{
auto baseContract = dynamic_cast<ContractDefinition const*>(&dereference(base->name()));
solAssert(baseContract, "");
if (baseContract->constructor() && base->arguments() && !base->arguments()->empty())
annotateBaseConstructorArguments(_contract, baseContract->constructor(), base.get());
}
}
// check that we get arguments for all base constructors that need it.
// If not mark the contract as abstract (not fully implemented)
for (ContractDefinition const* contract: bases)
if (FunctionDefinition const* constructor = contract->constructor())
if (contract != &_contract && !constructor->parameters().empty())
if (!_contract.annotation().baseConstructorArguments.count(constructor))
_contract.annotation().unimplementedFunctions.push_back(constructor);
}
void TypeChecker::annotateBaseConstructorArguments(
ContractDefinition const& _currentContract,
FunctionDefinition const* _baseConstructor,
ASTNode const* _argumentNode
)
{
solAssert(_baseConstructor, "");
solAssert(_argumentNode, "");
auto insertionResult = _currentContract.annotation().baseConstructorArguments.insert(
std::make_pair(_baseConstructor, _argumentNode)
);
if (!insertionResult.second)
{
ASTNode const* previousNode = insertionResult.first->second;
SourceLocation const* mainLocation = nullptr;
SecondarySourceLocation ssl;
if (
_currentContract.location().contains(previousNode->location()) ||
_currentContract.location().contains(_argumentNode->location())
)
{
mainLocation = &previousNode->location();
ssl.append("Second constructor call is here:", _argumentNode->location());
}
else
{
mainLocation = &_currentContract.location();
ssl.append("First constructor call is here: ", _argumentNode->location());
ssl.append("Second constructor call is here: ", previousNode->location());
}
m_errorReporter.declarationError(
*mainLocation,
ssl,
"Base constructor arguments given twice."
);
}
}
void TypeChecker::checkContractIllegalOverrides(ContractDefinition const& _contract)
{
// TODO unify this at a later point. for this we need to put the constness and the access specifier
// into the types
map<string, vector<FunctionDefinition const*>> functions;
map<string, ModifierDefinition const*> modifiers;
// We search from derived to base, so the stored item causes the error.
for (ContractDefinition const* contract: _contract.annotation().linearizedBaseContracts)
{
for (FunctionDefinition const* function: contract->definedFunctions())
{
if (function->isConstructor())
continue; // constructors can neither be overridden nor override anything
string const& name = function->name();
if (modifiers.count(name))
m_errorReporter.typeError(modifiers[name]->location(), "Override changes function to modifier.");
for (FunctionDefinition const* overriding: functions[name])
checkFunctionOverride(*overriding, *function);
functions[name].push_back(function);
}
for (ModifierDefinition const* modifier: contract->functionModifiers())
{
string const& name = modifier->name();
ModifierDefinition const*& override = modifiers[name];
if (!override)
override = modifier;
else if (ModifierType(*override) != ModifierType(*modifier))
m_errorReporter.typeError(override->location(), "Override changes modifier signature.");
if (!functions[name].empty())
m_errorReporter.typeError(override->location(), "Override changes modifier to function.");
}
}
}
void TypeChecker::checkFunctionOverride(FunctionDefinition const& function, FunctionDefinition const& super)
{
FunctionType functionType(function);
FunctionType superType(super);
if (!functionType.hasEqualParameterTypes(superType))
return;
if (!function.annotation().superFunction)
function.annotation().superFunction = &super;
if (function.visibility() != super.visibility())
{
// visibility is enforced to be external in interfaces, but a contract can override that with public
if (
super.inContractKind() == ContractDefinition::ContractKind::Interface &&
function.inContractKind() != ContractDefinition::ContractKind::Interface &&
function.visibility() == FunctionDefinition::Visibility::Public
)
return;
overrideError(function, super, "Overriding function visibility differs.");
}
else if (function.stateMutability() != super.stateMutability())
overrideError(
function,
super,
"Overriding function changes state mutability from \"" +
stateMutabilityToString(super.stateMutability()) +
"\" to \"" +
stateMutabilityToString(function.stateMutability()) +
"\"."
);
else if (functionType != superType)
overrideError(function, super, "Overriding function return types differ.");
}
void TypeChecker::overrideError(FunctionDefinition const& function, FunctionDefinition const& super, string message)
{
m_errorReporter.typeError(
function.location(),
SecondarySourceLocation().append("Overridden function is here:", super.location()),
message
);
}
void TypeChecker::checkContractExternalTypeClashes(ContractDefinition const& _contract)
{
map<string, vector<pair<Declaration const*, FunctionTypePointer>>> externalDeclarations;
for (ContractDefinition const* contract: _contract.annotation().linearizedBaseContracts)
{
for (FunctionDefinition const* f: contract->definedFunctions())
if (f->isPartOfExternalInterface())
{
auto functionType = make_shared<FunctionType>(*f);
// under non error circumstances this should be true
if (functionType->interfaceFunctionType())
externalDeclarations[functionType->externalSignature()].push_back(
make_pair(f, functionType)
);
}
for (VariableDeclaration const* v: contract->stateVariables())
if (v->isPartOfExternalInterface())
{
auto functionType = make_shared<FunctionType>(*v);
// under non error circumstances this should be true
if (functionType->interfaceFunctionType())
externalDeclarations[functionType->externalSignature()].push_back(
make_pair(v, functionType)
);
}
}
for (auto const& it: externalDeclarations)
for (size_t i = 0; i < it.second.size(); ++i)
for (size_t j = i + 1; j < it.second.size(); ++j)
if (!it.second[i].second->hasEqualParameterTypes(*it.second[j].second))
m_errorReporter.typeError(
it.second[j].first->location(),
"Function overload clash during conversion to external types for arguments."
);
}
void TypeChecker::checkLibraryRequirements(ContractDefinition const& _contract)
{
solAssert(_contract.isLibrary(), "");
if (!_contract.baseContracts().empty())
m_errorReporter.typeError(_contract.location(), "Library is not allowed to inherit.");
for (auto const& var: _contract.stateVariables())
if (!var->isConstant())
m_errorReporter.typeError(var->location(), "Library cannot have non-constant state variables");
}
void TypeChecker::checkDoubleStorageAssignment(Assignment const& _assignment)
{
TupleType const& lhs = dynamic_cast<TupleType const&>(*type(_assignment.leftHandSide()));
TupleType const& rhs = dynamic_cast<TupleType const&>(*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<ReferenceType const*>(lhs.components()[i].get());
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(
_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."
);
}
TypePointer TypeChecker::typeCheckABIDecodeAndRetrieveReturnType(FunctionCall const& _functionCall, bool _abiEncoderV2)
{
vector<ASTPointer<Expression const>> arguments = _functionCall.arguments();
if (arguments.size() != 2)
m_errorReporter.typeError(
_functionCall.location(),
"This function takes two arguments, but " +
toString(arguments.size()) +
" were provided."
);
if (arguments.size() >= 1 && !type(*arguments.front())->isImplicitlyConvertibleTo(ArrayType(DataLocation::Memory)))
m_errorReporter.typeError(
arguments.front()->location(),
"Invalid type for argument in function call. "
"Invalid implicit conversion from " +
type(*arguments.front())->toString() +
" to bytes memory requested."
);
TypePointer returnType = make_shared<TupleType>();
if (arguments.size() < 2)
return returnType;
// The following is a rather syntactic restriction, but we check it here anyway:
// The second argument has to be a tuple expression containing type names.
TupleExpression const* tupleExpression = dynamic_cast<TupleExpression const*>(arguments[1].get());
if (!tupleExpression)
{
m_errorReporter.typeError(
arguments[1]->location(),
"The second argument to \"abi.decode\" has to be a tuple of types."
);
return returnType;
}
vector<TypePointer> components;
for (auto const& typeArgument: tupleExpression->components())
{
solAssert(typeArgument, "");
if (TypeType const* argTypeType = dynamic_cast<TypeType const*>(type(*typeArgument).get()))
{
TypePointer actualType = argTypeType->actualType();
solAssert(actualType, "");
// We force memory because the parser currently cannot handle
// data locations. Furthermore, storage can be a little dangerous and
// calldata is not really implemented anyway.
actualType = ReferenceType::copyForLocationIfReference(DataLocation::Memory, actualType);
solAssert(
!actualType->dataStoredIn(DataLocation::CallData) &&
!actualType->dataStoredIn(DataLocation::Storage),
""
);
if (!actualType->fullEncodingType(false, _abiEncoderV2, false))
m_errorReporter.typeError(
typeArgument->location(),
"Decoding type " + actualType->toString(false) + " not supported."
);
components.push_back(actualType);
}
else
{
m_errorReporter.typeError(typeArgument->location(), "Argument has to be a type name.");
components.push_back(make_shared<TupleType>());
}
}
return make_shared<TupleType>(components);
}
void TypeChecker::endVisit(InheritanceSpecifier const& _inheritance)
{
auto base = dynamic_cast<ContractDefinition const*>(&dereference(_inheritance.name()));
solAssert(base, "Base contract not available.");
if (m_scope->contractKind() == ContractDefinition::ContractKind::Interface)
m_errorReporter.typeError(_inheritance.location(), "Interfaces cannot inherit.");
if (base->isLibrary())
m_errorReporter.typeError(_inheritance.location(), "Libraries cannot be inherited from.");
auto const& arguments = _inheritance.arguments();
TypePointers parameterTypes;
if (base->contractKind() != ContractDefinition::ContractKind::Interface)
// 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(
_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)
if (!type(*(*arguments)[i])->isImplicitlyConvertibleTo(*parameterTypes[i]))
m_errorReporter.typeError(
(*arguments)[i]->location(),
"Invalid type for argument in constructor call. "
"Invalid implicit conversion from " +
type(*(*arguments)[i])->toString() +
" to " +
parameterTypes[i]->toString() +
" requested."
);
}
}
void TypeChecker::endVisit(UsingForDirective const& _usingFor)
{
ContractDefinition const* library = dynamic_cast<ContractDefinition const*>(
_usingFor.libraryName().annotation().referencedDeclaration
);
if (!library || !library->isLibrary())
m_errorReporter.fatalTypeError(_usingFor.libraryName().location(), "Library name expected.");
}
bool TypeChecker::visit(StructDefinition const& _struct)
{
for (ASTPointer<VariableDeclaration> const& member: _struct.members())
if (!type(*member)->canBeStored())
m_errorReporter.typeError(member->location(), "Type cannot be used in struct.");
// Check recursion, fatal error if detected.
auto visitor = [&](StructDefinition const& _struct, CycleDetector<StructDefinition>& _cycleDetector, size_t _depth)
{
if (_depth >= 256)
m_errorReporter.fatalDeclarationError(_struct.location(), "Struct definition exhausting cyclic dependency validator.");
for (ASTPointer<VariableDeclaration> const& member: _struct.members())
{
Type const* memberType = type(*member).get();
while (auto arrayType = dynamic_cast<ArrayType const*>(memberType))
{
if (arrayType->isDynamicallySized())
break;
memberType = arrayType->baseType().get();
}
if (auto structType = dynamic_cast<StructType const*>(memberType))
if (_cycleDetector.run(structType->structDefinition()))
return;
}
};
if (CycleDetector<StructDefinition>(visitor).run(_struct) != nullptr)
m_errorReporter.fatalTypeError(_struct.location(), "Recursive struct definition.");
bool insideStruct = true;
swap(insideStruct, m_insideStruct);
ASTNode::listAccept(_struct.members(), *this);
m_insideStruct = insideStruct;
return false;
}
bool TypeChecker::visit(FunctionDefinition const& _function)
{
bool isLibraryFunction =
dynamic_cast<ContractDefinition const*>(_function.scope()) &&
dynamic_cast<ContractDefinition const*>(_function.scope())->isLibrary();
if (_function.isPayable())
{
if (isLibraryFunction)
m_errorReporter.typeError(_function.location(), "Library functions cannot be payable.");
if (!_function.isConstructor() && !_function.isFallback() && !_function.isPartOfExternalInterface())
m_errorReporter.typeError(_function.location(), "Internal functions cannot be payable.");
}
for (ASTPointer<VariableDeclaration> const& var: _function.parameters() + _function.returnParameters())
{
if (
type(*var)->category() == Type::Category::Mapping &&
!type(*var)->dataStoredIn(DataLocation::Storage)
)
m_errorReporter.typeError(var->location(), "Mapping types can only have a data location of \"storage\".");
else if (
!type(*var)->canLiveOutsideStorage() &&
_function.visibility() > FunctionDefinition::Visibility::Internal
)
m_errorReporter.typeError(var->location(), "Type is required to live outside storage.");
if (_function.visibility() >= FunctionDefinition::Visibility::Public && !(type(*var)->interfaceType(isLibraryFunction)))
m_errorReporter.fatalTypeError(var->location(), "Internal or recursive type is not allowed for public or external functions.");
if (
_function.visibility() > FunctionDefinition::Visibility::Internal &&
!_function.sourceUnit().annotation().experimentalFeatures.count(ExperimentalFeature::ABIEncoderV2) &&
!typeSupportedByOldABIEncoder(*type(*var))
)
m_errorReporter.typeError(
var->location(),
"This type is only supported in the new experimental ABI encoder. "
"Use \"pragma experimental ABIEncoderV2;\" to enable the feature."
);
var->accept(*this);
}
set<Declaration const*> modifiers;
for (ASTPointer<ModifierInvocation> const& modifier: _function.modifiers())
{
visitManually(
*modifier,
_function.isConstructor() ?
dynamic_cast<ContractDefinition const&>(*_function.scope()).annotation().linearizedBaseContracts :
vector<ContractDefinition const*>()
);
Declaration const* decl = &dereference(*modifier->name());
if (modifiers.count(decl))
{
if (dynamic_cast<ContractDefinition const*>(decl))
m_errorReporter.declarationError(modifier->location(), "Base constructor already provided.");
}
else
modifiers.insert(decl);
}
if (m_scope->contractKind() == ContractDefinition::ContractKind::Interface)
{
if (_function.isImplemented())
m_errorReporter.typeError(_function.location(), "Functions in interfaces cannot have an implementation.");
if (_function.visibility() != FunctionDefinition::Visibility::External)
m_errorReporter.typeError(_function.location(), "Functions in interfaces must be declared external.");
if (_function.isConstructor())
m_errorReporter.typeError(_function.location(), "Constructor cannot be defined in interfaces.");
}
else if (m_scope->contractKind() == ContractDefinition::ContractKind::Library)
if (_function.isConstructor())
m_errorReporter.typeError(_function.location(), "Constructor cannot be defined in libraries.");
if (_function.isImplemented())
_function.body().accept(*this);
else if (_function.isConstructor())
m_errorReporter.typeError(_function.location(), "Constructor must be implemented if declared.");
else if (isLibraryFunction && _function.visibility() <= FunctionDefinition::Visibility::Internal)
m_errorReporter.typeError(_function.location(), "Internal library function must be implemented if declared.");
return false;
}
bool TypeChecker::visit(VariableDeclaration const& _variable)
{
// Forbid any variable declarations inside interfaces unless they are part of
// * a function's input/output parameters,
// * or inside of a struct definition.
if (
m_scope->contractKind() == ContractDefinition::ContractKind::Interface
&& !_variable.isCallableParameter()
&& !m_insideStruct
)
m_errorReporter.typeError(_variable.location(), "Variables cannot be declared in interfaces.");
// Variables can be declared without type (with "var"), in which case the first assignment
// sets the type.
// Note that assignments before the first declaration are legal because of the special scoping
// rules inherited from JavaScript.
// 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, "Failed to infer variable type.");
if (_variable.value())
expectType(*_variable.value(), *varType);
if (_variable.isConstant())
{
if (!_variable.type()->isValueType())
{
bool allowed = false;
if (auto arrayType = dynamic_cast<ArrayType const*>(_variable.type().get()))
allowed = arrayType->isByteArray();
if (!allowed)
m_errorReporter.typeError(_variable.location(), "Constants of non-value type not yet implemented.");
}
if (!_variable.value())
m_errorReporter.typeError(_variable.location(), "Uninitialized \"constant\" variable.");
else if (!_variable.value()->annotation().isPure)
m_errorReporter.typeError(
_variable.value()->location(),
"Initial value for constant variable has to be compile-time constant."
);
}
if (!_variable.isStateVariable())
{
if (varType->dataStoredIn(DataLocation::Memory) || varType->dataStoredIn(DataLocation::CallData))
if (!varType->canLiveOutsideStorage())
m_errorReporter.typeError(_variable.location(), "Type " + varType->toString() + " is only valid in storage.");
}
else if (
_variable.visibility() >= VariableDeclaration::Visibility::Public &&
!FunctionType(_variable).interfaceFunctionType()
)
m_errorReporter.typeError(_variable.location(), "Internal or recursive type is not allowed for public state variables.");
switch (varType->category())
{
case Type::Category::Array:
if (auto arrayType = dynamic_cast<ArrayType const*>(varType.get()))
if (
((arrayType->location() == DataLocation::Memory) ||
(arrayType->location() == DataLocation::CallData)) &&
!arrayType->validForCalldata()
)
m_errorReporter.typeError(_variable.location(), "Array is too large to be encoded.");
break;
case Type::Category::Mapping:
if (auto mappingType = dynamic_cast<MappingType const*>(varType.get()))
if (
mappingType->keyType()->isDynamicallySized() &&
_variable.visibility() == Declaration::Visibility::Public
)
m_errorReporter.typeError(_variable.location(), "Dynamically-sized keys for public mappings are not supported.");
break;
default:
break;
}
return false;
}
void TypeChecker::visitManually(
ModifierInvocation const& _modifier,
vector<ContractDefinition const*> const& _bases
)
{
std::vector<ASTPointer<Expression>> const& arguments =
_modifier.arguments() ? *_modifier.arguments() : std::vector<ASTPointer<Expression>>();
for (ASTPointer<Expression> const& argument: arguments)
argument->accept(*this);
_modifier.name()->accept(*this);
auto const* declaration = &dereference(*_modifier.name());
vector<ASTPointer<VariableDeclaration>> emptyParameterList;
vector<ASTPointer<VariableDeclaration>> const* parameters = nullptr;
if (auto modifierDecl = dynamic_cast<ModifierDefinition const*>(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(_modifier.location(), "Referenced declaration is neither modifier nor base class.");
return;
}
if (parameters->size() != arguments.size())
{
m_errorReporter.typeError(
_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)
if (!type(*arguments[i])->isImplicitlyConvertibleTo(*type(*(*parameters)[i])))
m_errorReporter.typeError(
arguments[i]->location(),
"Invalid type for argument in modifier invocation. "
"Invalid implicit conversion from " +
type(*arguments[i])->toString() +
" to " +
type(*(*parameters)[i])->toString() +
" requested."
);
}
bool TypeChecker::visit(EventDefinition const& _eventDef)
{
solAssert(_eventDef.visibility() > Declaration::Visibility::Internal, "");
unsigned numIndexed = 0;
for (ASTPointer<VariableDeclaration> const& var: _eventDef.parameters())
{
if (var->isIndexed())
{
numIndexed++;
if (
_eventDef.sourceUnit().annotation().experimentalFeatures.count(ExperimentalFeature::ABIEncoderV2) &&
dynamic_cast<ReferenceType const*>(type(*var).get())
)
m_errorReporter.typeError(
var->location(),
"Indexed reference types cannot yet be used with ABIEncoderV2."
);
}
if (!type(*var)->canLiveOutsideStorage())
m_errorReporter.typeError(var->location(), "Type is required to live outside storage.");
if (!type(*var)->interfaceType(false))
m_errorReporter.typeError(var->location(), "Internal or recursive type is not allowed as event parameter type.");
if (
!_eventDef.sourceUnit().annotation().experimentalFeatures.count(ExperimentalFeature::ABIEncoderV2) &&
!typeSupportedByOldABIEncoder(*type(*var))
)
m_errorReporter.typeError(
var->location(),
"This type is only supported in the new experimental ABI encoder. "
"Use \"pragma experimental ABIEncoderV2;\" to enable the feature."
);
}
if (_eventDef.isAnonymous() && numIndexed > 4)
m_errorReporter.typeError(_eventDef.location(), "More than 4 indexed arguments for anonymous event.");
else if (!_eventDef.isAnonymous() && numIndexed > 3)
m_errorReporter.typeError(_eventDef.location(), "More than 3 indexed arguments for event.");
return false;
}
void TypeChecker::endVisit(FunctionTypeName const& _funType)
{
FunctionType const& fun = dynamic_cast<FunctionType const&>(*_funType.annotation().type);
if (fun.kind() == FunctionType::Kind::External)
if (!fun.canBeUsedExternally(false))
m_errorReporter.typeError(_funType.location(), "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.
julia::ExternalIdentifierAccess::Resolver identifierAccess = [&](
assembly::Identifier const& _identifier,
julia::IdentifierContext _context,
bool
)
{
auto ref = _inlineAssembly.annotation().externalReferences.find(&_identifier);
if (ref == _inlineAssembly.annotation().externalReferences.end())
return size_t(-1);
Declaration const* declaration = ref->second.declaration;
solAssert(!!declaration, "");
bool requiresStorage = ref->second.isSlot || ref->second.isOffset;
if (auto var = dynamic_cast<VariableDeclaration const*>(declaration))
{
if (var->isConstant())
{
m_errorReporter.typeError(_identifier.location, "Constant variables not supported by inline assembly.");
return size_t(-1);
}
else if (requiresStorage)
{
if (!var->isStateVariable() && !var->type()->dataStoredIn(DataLocation::Storage))
{
m_errorReporter.typeError(_identifier.location, "The suffixes _offset and _slot can only be used on storage variables.");
return size_t(-1);
}
else if (_context != julia::IdentifierContext::RValue)
{
m_errorReporter.typeError(_identifier.location, "Storage variables cannot be assigned to.");
return size_t(-1);
}
}
else if (!var->isLocalVariable())
{
m_errorReporter.typeError(_identifier.location, "Only local variables are supported. To access storage variables, use the _slot and _offset suffixes.");
return size_t(-1);
}
else if (var->type()->dataStoredIn(DataLocation::Storage))
{
m_errorReporter.typeError(_identifier.location, "You have to use the _slot or _offset suffix to access storage reference variables.");
return size_t(-1);
}
else if (var->type()->sizeOnStack() != 1)
{
if (var->type()->dataStoredIn(DataLocation::CallData))
m_errorReporter.typeError(_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(_identifier.location, "Only types that use one stack slot are supported.");
return size_t(-1);
}
}
else if (requiresStorage)
{
m_errorReporter.typeError(_identifier.location, "The suffixes _offset and _slot can only be used on storage variables.");
return size_t(-1);
}
else if (_context == julia::IdentifierContext::LValue)
{
m_errorReporter.typeError(_identifier.location, "Only local variables can be assigned to in inline assembly.");
return size_t(-1);
}
if (_context == julia::IdentifierContext::RValue)
{
solAssert(!!declaration->type(), "Type of declaration required but not yet determined.");
if (dynamic_cast<FunctionDefinition const*>(declaration))
{
}
else if (dynamic_cast<VariableDeclaration const*>(declaration))
{
}
else if (auto contract = dynamic_cast<ContractDefinition const*>(declaration))
{
if (!contract->isLibrary())
{
m_errorReporter.typeError(_identifier.location, "Expected a library.");
return size_t(-1);
}
}
else
return size_t(-1);
}
ref->second.valueSize = 1;
return size_t(1);
};
solAssert(!_inlineAssembly.annotation().analysisInfo, "");
_inlineAssembly.annotation().analysisInfo = make_shared<assembly::AsmAnalysisInfo>();
assembly::AsmAnalyzer analyzer(
*_inlineAssembly.annotation().analysisInfo,
m_errorReporter,
m_evmVersion,
Error::Type::SyntaxError,
assembly::AsmFlavour::Loose,
identifierAccess
);
if (!analyzer.analyze(_inlineAssembly.operations()))
return false;
return true;
}
bool TypeChecker::visit(IfStatement const& _ifStatement)
{
expectType(_ifStatement.condition(), BoolType());
_ifStatement.trueStatement().accept(*this);
if (_ifStatement.falseStatement())
_ifStatement.falseStatement()->accept(*this);
return false;
}
bool TypeChecker::visit(WhileStatement const& _whileStatement)
{
expectType(_whileStatement.condition(), BoolType());
_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(), BoolType());
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(_return.location(), "Return arguments required.");
return;
}
if (!params)
{
m_errorReporter.typeError(_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<TupleType const*>(type(*_return.expression()).get()))
{
if (tupleType->components().size() != params->parameters().size())
m_errorReporter.typeError(_return.location(), "Different number of arguments in return statement than in returns declaration.");
else if (!tupleType->isImplicitlyConvertibleTo(TupleType(returnTypes)))
m_errorReporter.typeError(
_return.expression()->location(),
"Return argument type " +
type(*_return.expression())->toString() +
" is not implicitly convertible to expected type " +
TupleType(returnTypes).toString(false) +
"."
);
}
else if (params->parameters().size() != 1)
m_errorReporter.typeError(_return.location(), "Different number of arguments in return statement than in returns declaration.");
else
{
TypePointer const& expected = type(*params->parameters().front());
if (!type(*_return.expression())->isImplicitlyConvertibleTo(*expected))
m_errorReporter.typeError(
_return.expression()->location(),
"Return argument type " +
type(*_return.expression())->toString() +
" is not implicitly convertible to expected type (type of first return variable) " +
expected->toString() +
"."
);
}
}
void TypeChecker::endVisit(EmitStatement const& _emit)
{
if (
_emit.eventCall().annotation().kind != FunctionCallKind::FunctionCall ||
type(_emit.eventCall().expression())->category() != Type::Category::Function ||
dynamic_cast<FunctionType const&>(*type(_emit.eventCall().expression())).kind() != FunctionType::Kind::Event
)
m_errorReporter.typeError(_emit.eventCall().expression().location(), "Expression has to be an event invocation.");
m_insideEmitStatement = false;
}
namespace
{
/**
* @returns a suggested left-hand-side of a multi-variable declaration contairing
* the variable declarations given in @a _decls.
*/
string createTupleDecl(vector<ASTPointer<VariableDeclaration>> const& _decls)
{
vector<string> components;
for (ASTPointer<VariableDeclaration> const& decl: _decls)
if (decl)
{
solAssert(decl->annotation().type, "");
components.emplace_back(decl->annotation().type->toString(false) + " " + decl->name());
}
else
components.emplace_back();
if (_decls.size() == 1)
return components.front();
else
return "(" + boost::algorithm::join(components, ", ") + ")";
}
bool typeCanBeExpressed(vector<ASTPointer<VariableDeclaration>> const& decls)
{
for (ASTPointer<VariableDeclaration> const& decl: decls)
{
// skip empty tuples (they can be expressed of course)
if (!decl)
continue;
if (!decl->annotation().type)
return false;
if (auto functionType = dynamic_cast<FunctionType const*>(decl->annotation().type.get()))
if (
functionType->kind() != FunctionType::Kind::Internal &&
functionType->kind() != FunctionType::Kind::External
)
return false;
}
return true;
}
}
bool TypeChecker::visit(VariableDeclarationStatement const& _statement)
{
if (!_statement.initialValue())
{
// No initial value is only permitted for single variables with specified type.
if (_statement.declarations().size() != 1 || !_statement.declarations().front())
{
if (boost::algorithm::all_of_equal(_statement.declarations(), nullptr))
{
// The syntax checker has already generated an error for this case (empty LHS tuple).
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;
}
else
// Bailing out *fatal* here, as those (untyped) vars may be used later, and diagnostics wouldn't be helpful then.
m_errorReporter.fatalTypeError(_statement.location(), "Use of the \"var\" keyword is disallowed.");
}
VariableDeclaration const& varDecl = *_statement.declarations().front();
if (!varDecl.annotation().type)
m_errorReporter.fatalTypeError(_statement.location(), "Use of the \"var\" keyword is disallowed.");
if (auto ref = dynamic_cast<ReferenceType const*>(type(varDecl).get()))
{
if (ref->dataStoredIn(DataLocation::Storage))
{
string errorText{"Uninitialized storage pointer."};
if (varDecl.referenceLocation() == VariableDeclaration::Location::Default)
errorText += " Did you mean '<type> memory " + varDecl.name() + "'?";
solAssert(m_scope, "");
m_errorReporter.declarationError(varDecl.location(), errorText);
}
}
else if (dynamic_cast<MappingType const*>(type(varDecl).get()))
m_errorReporter.typeError(
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<TupleType const*>(type(*_statement.initialValue()).get()))
valueTypes = tupleType->components();
else
valueTypes = TypePointers{type(*_statement.initialValue())};
vector<ASTPointer<VariableDeclaration>> 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(
_statement.location(),
"Different number of components on the left hand side (" +
toString(variables.size()) +
") than on the right hand side (" +
toString(valueTypes.size()) +
")."
);
bool autoTypeDeductionNeeded = false;
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, "");
if (!var.annotation().type)
{
autoTypeDeductionNeeded = true;
// Infer type from value.
solAssert(!var.typeName(), "");
var.annotation().type = valueComponentType->mobileType();
if (!var.annotation().type)
{
if (valueComponentType->category() == Type::Category::RationalNumber)
m_errorReporter.fatalTypeError(
_statement.initialValue()->location(),
"Invalid rational " +
valueComponentType->toString() +
" (absolute value too large or division by zero)."
);
else
solAssert(false, "");
}
else if (*var.annotation().type == TupleType())
m_errorReporter.typeError(
var.location(),
"Cannot declare variable with void (empty tuple) type."
);
else if (valueComponentType->category() == Type::Category::RationalNumber)
{
string typeName = var.annotation().type->toString(true);
string extension;
if (auto type = dynamic_cast<IntegerType const*>(var.annotation().type.get()))
{
unsigned numBits = type->numBits();
bool isSigned = type->isSigned();
solAssert(numBits > 0, "");
string minValue;
string maxValue;
if (isSigned)
{
numBits--;
minValue = "-" + bigint(bigint(1) << numBits).str();
}
else
minValue = "0";
maxValue = bigint((bigint(1) << numBits) - 1).str();
extension = ", which can hold values between " + minValue + " and " + maxValue;
}
else
solAssert(dynamic_cast<FixedPointType const*>(var.annotation().type.get()), "Unknown type.");
}
var.accept(*this);
}
else
{
var.accept(*this);
if (!valueComponentType->isImplicitlyConvertibleTo(*var.annotation().type))
{
if (
valueComponentType->category() == Type::Category::RationalNumber &&
dynamic_cast<RationalNumberType const&>(*valueComponentType).isFractional() &&
valueComponentType->mobileType()
)
m_errorReporter.typeError(
_statement.location(),
"Type " +
valueComponentType->toString() +
" is not implicitly convertible to expected type " +
var.annotation().type->toString() +
". Try converting to type " +
valueComponentType->mobileType()->toString() +
" or use an explicit conversion."
);
else
m_errorReporter.typeError(
_statement.location(),
"Type " +
valueComponentType->toString() +
" is not implicitly convertible to expected type " +
var.annotation().type->toString() +
"."
);
}
}
}
if (autoTypeDeductionNeeded)
{
if (!typeCanBeExpressed(variables))
m_errorReporter.syntaxError(
_statement.location(),
"Use of the \"var\" keyword is disallowed. "
"Type cannot be expressed in syntax."
);
else
m_errorReporter.syntaxError(
_statement.location(),
"Use of the \"var\" keyword is disallowed. "
"Use explicit declaration `" + createTupleDecl(variables) + " = ...´ instead."
);
}
return false;
}
void TypeChecker::endVisit(ExpressionStatement const& _statement)
{
if (type(_statement.expression())->category() == Type::Category::RationalNumber)
if (!dynamic_cast<RationalNumberType const&>(*type(_statement.expression())).mobileType())
m_errorReporter.typeError(_statement.expression().location(), "Invalid rational number.");
if (auto call = dynamic_cast<FunctionCall const*>(&_statement.expression()))
{
if (auto callType = dynamic_cast<FunctionType const*>(type(call->expression()).get()))
{
auto kind = callType->kind();
if (
kind == FunctionType::Kind::BareCall ||
kind == FunctionType::Kind::BareCallCode ||
kind == FunctionType::Kind::BareDelegateCall ||
kind == FunctionType::Kind::BareStaticCall
)
m_errorReporter.warning(_statement.location(), "Return value of low-level calls not used.");
else if (kind == FunctionType::Kind::Send)
m_errorReporter.warning(_statement.location(), "Failure condition of 'send' ignored. Consider using 'transfer' instead.");
}
}
}
bool TypeChecker::visit(Conditional const& _conditional)
{
expectType(_conditional.condition(), BoolType());
_conditional.trueExpression().accept(*this);
_conditional.falseExpression().accept(*this);
TypePointer trueType = type(_conditional.trueExpression())->mobileType();
TypePointer falseType = type(_conditional.falseExpression())->mobileType();
if (!trueType)
m_errorReporter.fatalTypeError(_conditional.trueExpression().location(), "Invalid mobile type.");
if (!falseType)
m_errorReporter.fatalTypeError(_conditional.falseExpression().location(), "Invalid mobile type.");
TypePointer commonType = Type::commonType(trueType, falseType);
if (!commonType)
{
m_errorReporter.typeError(
_conditional.location(),
"True expression's type " +
trueType->toString() +
" doesn't 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().type = commonType;
_conditional.annotation().isPure =
_conditional.condition().annotation().isPure &&
_conditional.trueExpression().annotation().isPure &&
_conditional.falseExpression().annotation().isPure;
if (_conditional.annotation().lValueRequested)
m_errorReporter.typeError(
_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<TupleExpression const*>(&_expression))
{
auto const* tupleType = dynamic_cast<TupleType const*>(&_type);
auto const& types = tupleType ? tupleType->components() : vector<TypePointer> { _type.shared_from_this() };
solAssert(tupleExpression->components().size() == types.size(), "");
for (size_t i = 0; i < types.size(); i++)
if (types[i])
{
solAssert(!!tupleExpression->components()[i], "");
checkExpressionAssignment(*types[i], *tupleExpression->components()[i]);
}
}
else if (_type.category() == Type::Category::Mapping)
{
bool isLocalOrReturn = false;
if (auto const* identifier = dynamic_cast<Identifier const*>(&_expression))
if (auto const *variableDeclaration = dynamic_cast<VariableDeclaration const*>(identifier->annotation().referencedDeclaration))
if (variableDeclaration->isLocalOrReturn())
isLocalOrReturn = true;
if (!isLocalOrReturn)
m_errorReporter.typeError(_expression.location(), "Mappings cannot be assigned to.");
}
}
bool TypeChecker::visit(Assignment const& _assignment)
{
requireLValue(_assignment.leftHandSide());
TypePointer t = type(_assignment.leftHandSide());
_assignment.annotation().type = t;
checkExpressionAssignment(*t, _assignment.leftHandSide());
if (TupleType const* tupleType = dynamic_cast<TupleType const*>(t.get()))
{
if (_assignment.assignmentOperator() != Token::Assign)
m_errorReporter.typeError(
_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 = make_shared<TupleType>();
expectType(_assignment.rightHandSide(), *tupleType);
// expectType does not cause fatal errors, so we have to check again here.
if (dynamic_cast<TupleType const*>(type(_assignment.rightHandSide()).get()))
checkDoubleStorageAssignment(_assignment);
}
else if (_assignment.assignmentOperator() == Token::Assign)
expectType(_assignment.rightHandSide(), *t);
else
{
// compound assignment
_assignment.rightHandSide().accept(*this);
TypePointer resultType = t->binaryOperatorResult(
Token::AssignmentToBinaryOp(_assignment.assignmentOperator()),
type(_assignment.rightHandSide())
);
if (!resultType || *resultType != *t)
m_errorReporter.typeError(
_assignment.location(),
"Operator " +
string(Token::toString(_assignment.assignmentOperator())) +
" not compatible with types " +
t->toString() +
" and " +
type(_assignment.rightHandSide())->toString()
);
}
return false;
}
bool TypeChecker::visit(TupleExpression const& _tuple)
{
vector<ASTPointer<Expression>> const& components = _tuple.components();
TypePointers types;
if (_tuple.annotation().lValueRequested)
{
if (_tuple.isInlineArray())
m_errorReporter.fatalTypeError(_tuple.location(), "Inline array type cannot be declared as LValue.");
for (auto const& component: components)
if (component)
{
requireLValue(*component);
types.push_back(type(*component));
}
else
types.push_back(TypePointer());
if (components.size() == 1)
_tuple.annotation().type = type(*components[0]);
else
_tuple.annotation().type = make_shared<TupleType>(types);
// If some of the components are not LValues, the error is reported above.
_tuple.annotation().isLValue = true;
}
else
{
bool isPure = true;
TypePointer inlineArrayType;
for (size_t i = 0; i < components.size(); ++i)
{
if (!components[i])
m_errorReporter.fatalTypeError(_tuple.location(), "Tuple component cannot be empty.");
else if (components[i])
{
components[i]->accept(*this);
types.push_back(type(*components[i]));
if (types[i]->category() == Type::Category::Tuple)
if (dynamic_cast<TupleType const&>(*types[i]).components().empty())
{
if (_tuple.isInlineArray())
m_errorReporter.fatalTypeError(components[i]->location(), "Array component cannot be empty.");
m_errorReporter.typeError(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<RationalNumberType const&>(*types[i]).mobileType())
m_errorReporter.fatalTypeError(components[i]->location(), "Invalid rational number.");
if (_tuple.isInlineArray())
solAssert(!!types[i], "Inline array cannot have empty components");
if (_tuple.isInlineArray())
{
if ((i == 0 || inlineArrayType) && !types[i]->mobileType())
m_errorReporter.fatalTypeError(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;
}
else
types.push_back(TypePointer());
}
_tuple.annotation().isPure = isPure;
if (_tuple.isInlineArray())
{
if (!inlineArrayType)
m_errorReporter.fatalTypeError(_tuple.location(), "Unable to deduce common type for array elements.");
_tuple.annotation().type = make_shared<ArrayType>(DataLocation::Memory, inlineArrayType, types.size());
}
else
{
if (components.size() == 1)
_tuple.annotation().type = type(*components[0]);
else
_tuple.annotation().type = make_shared<TupleType>(types);
}
}
return false;
}
bool TypeChecker::visit(UnaryOperation const& _operation)
{
// Inc, Dec, Add, Sub, Not, BitNot, Delete
Token::Value op = _operation.getOperator();
bool const modifying = (op == Token::Value::Inc || op == Token::Value::Dec || op == Token::Value::Delete);
if (modifying)
requireLValue(_operation.subExpression());
else
_operation.subExpression().accept(*this);
TypePointer const& subExprType = type(_operation.subExpression());
TypePointer t = type(_operation.subExpression())->unaryOperatorResult(op);
if (!t)
{
m_errorReporter.typeError(
_operation.location(),
"Unary operator " +
string(Token::toString(op)) +
" cannot be applied to type " +
subExprType->toString()
);
t = subExprType;
}
_operation.annotation().type = t;
_operation.annotation().isPure = !modifying && _operation.subExpression().annotation().isPure;
return false;
}
void TypeChecker::endVisit(BinaryOperation const& _operation)
{
TypePointer const& leftType = type(_operation.leftExpression());
TypePointer const& rightType = type(_operation.rightExpression());
TypePointer commonType = leftType->binaryOperatorResult(_operation.getOperator(), rightType);
if (!commonType)
{
m_errorReporter.typeError(
_operation.location(),
"Operator " +
string(Token::toString(_operation.getOperator())) +
" not compatible with types " +
leftType->toString() +
" and " +
rightType->toString()
);
commonType = leftType;
}
_operation.annotation().commonType = commonType;
_operation.annotation().type =
Token::isCompareOp(_operation.getOperator()) ?
make_shared<BoolType>() :
commonType;
_operation.annotation().isPure =
_operation.leftExpression().annotation().isPure &&
_operation.rightExpression().annotation().isPure;
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<IntegerType const&>(*commonType).numBits() != 256
) || (
commonType->category() == Type::Category::FixedPoint &&
dynamic_cast<FixedPointType const&>(*commonType).numBits() != 256
))
m_errorReporter.warning(
_operation.location(),
"Result of " + operation + " has type " + commonType->toString() + " and thus "
"might overflow. Silence this warning by converting the literal to the "
"expected type."
);
}
}
bool TypeChecker::visit(FunctionCall const& _functionCall)
{
bool isPositionalCall = _functionCall.names().empty();
vector<ASTPointer<Expression const>> arguments = _functionCall.arguments();
vector<ASTPointer<ASTString>> const& argumentNames = _functionCall.names();
bool isPure = true;
// We need to check arguments' type first as they will be needed for overload resolution.
shared_ptr<TypePointers> argumentTypes;
if (isPositionalCall)
argumentTypes = make_shared<TypePointers>();
for (ASTPointer<Expression const> const& argument: arguments)
{
argument->accept(*this);
if (!argument->annotation().isPure)
isPure = false;
// only store them for positional calls
if (isPositionalCall)
argumentTypes->push_back(type(*argument));
}
if (isPositionalCall)
_functionCall.expression().annotation().argumentTypes = move(argumentTypes);
_functionCall.expression().accept(*this);
TypePointer expressionType = type(_functionCall.expression());
if (auto const* typeType = dynamic_cast<TypeType const*>(expressionType.get()))
{
if (typeType->actualType()->category() == Type::Category::Struct)
_functionCall.annotation().kind = FunctionCallKind::StructConstructorCall;
else
_functionCall.annotation().kind = FunctionCallKind::TypeConversion;
}
else
_functionCall.annotation().kind = FunctionCallKind::FunctionCall;
solAssert(_functionCall.annotation().kind != FunctionCallKind::Unset, "");
if (_functionCall.annotation().kind == FunctionCallKind::TypeConversion)
{
TypeType const& t = dynamic_cast<TypeType const&>(*expressionType);
TypePointer resultType = t.actualType();
if (arguments.size() != 1)
m_errorReporter.typeError(_functionCall.location(), "Exactly one argument expected for explicit type conversion.");
else if (!isPositionalCall)
m_errorReporter.typeError(_functionCall.location(), "Type conversion cannot allow named arguments.");
else
{
TypePointer const& argType = type(*arguments.front());
// Resulting data location is memory unless we are converting from a reference
// type with a different data location.
// (data location cannot yet be specified for type conversions)
DataLocation dataLoc = DataLocation::Memory;
if (auto argRefType = dynamic_cast<ReferenceType const*>(argType.get()))
dataLoc = argRefType->location();
resultType = ReferenceType::copyForLocationIfReference(dataLoc, resultType);
if (!argType->isExplicitlyConvertibleTo(*resultType))
m_errorReporter.typeError(
_functionCall.location(),
"Explicit type conversion not allowed from \"" +
argType->toString() +
"\" to \"" +
resultType->toString() +
"\"."
);
}
_functionCall.annotation().type = resultType;
_functionCall.annotation().isPure = isPure;
return false;
}
// Actual function call or struct constructor call.
FunctionTypePointer functionType;
/// For error message: Struct members that were removed during conversion to memory.
set<string> membersRemovedForStructConstructor;
if (_functionCall.annotation().kind == FunctionCallKind::StructConstructorCall)
{
TypeType const& t = dynamic_cast<TypeType const&>(*expressionType);
auto const& structType = dynamic_cast<StructType const&>(*t.actualType());
functionType = structType.constructorType();
membersRemovedForStructConstructor = structType.membersMissingInMemory();
_functionCall.annotation().isPure = isPure;
}
else if ((functionType = dynamic_pointer_cast<FunctionType const>(expressionType)))
_functionCall.annotation().isPure =
isPure &&
_functionCall.expression().annotation().isPure &&
functionType->isPure();
bool allowDynamicTypes = m_evmVersion.supportsReturndata();
if (!functionType)
{
m_errorReporter.typeError(_functionCall.location(), "Type is not callable");
_functionCall.annotation().type = make_shared<TupleType>();
return false;
}
if (functionType->kind() == FunctionType::Kind::BareStaticCall && !m_evmVersion.hasStaticCall())
m_errorReporter.typeError(_functionCall.location(), "\"staticcall\" is not supported by the VM version.");
auto returnTypes =
allowDynamicTypes ?
functionType->returnParameterTypes() :
functionType->returnParameterTypesWithoutDynamicTypes();
if (returnTypes.size() == 1)
_functionCall.annotation().type = returnTypes.front();
else
_functionCall.annotation().type = make_shared<TupleType>(returnTypes);
if (auto functionName = dynamic_cast<Identifier const*>(&_functionCall.expression()))
{
if (functionName->name() == "sha3" && functionType->kind() == FunctionType::Kind::KECCAK256)
m_errorReporter.typeError(_functionCall.location(), "\"sha3\" has been deprecated in favour of \"keccak256\"");
else if (functionName->name() == "suicide" && functionType->kind() == FunctionType::Kind::Selfdestruct)
m_errorReporter.typeError(_functionCall.location(), "\"suicide\" has been deprecated in favour of \"selfdestruct\"");
}
if (!m_insideEmitStatement && functionType->kind() == FunctionType::Kind::Event)
m_errorReporter.typeError(_functionCall.location(), "Event invocations have to be prefixed by \"emit\".");
TypePointers parameterTypes = functionType->parameterTypes();
if (!functionType->padArguments())
{
for (size_t i = 0; i < arguments.size(); ++i)
{
auto const& argType = type(*arguments[i]);
if (auto literal = dynamic_cast<RationalNumberType const*>(argType.get()))
{
if (literal->mobileType())
m_errorReporter.typeError(
arguments[i]->location(),
"Cannot perform packed encoding for a literal. Please convert it to an explicit type first."
);
else
{
/* If no mobile type is available an error will be raised elsewhere. */
solAssert(m_errorReporter.hasErrors(), "");
}
}
}
}
bool const abiEncoderV2 = m_scope->sourceUnit().annotation().experimentalFeatures.count(ExperimentalFeature::ABIEncoderV2);
if (functionType->kind() == FunctionType::Kind::ABIDecode)
_functionCall.annotation().type = typeCheckABIDecodeAndRetrieveReturnType(_functionCall, abiEncoderV2);
else if (functionType->takesArbitraryParameters() && arguments.size() < parameterTypes.size())
{
solAssert(_functionCall.annotation().kind == FunctionCallKind::FunctionCall, "");
m_errorReporter.typeError(
_functionCall.location(),
"Need at least " +
toString(parameterTypes.size()) +
" arguments for function call, but provided only " +
toString(arguments.size()) +
"."
);
}
else if (!functionType->takesArbitraryParameters() && parameterTypes.size() != arguments.size())
{
bool isStructConstructorCall = _functionCall.annotation().kind == FunctionCallKind::StructConstructorCall;
string msg =
"Wrong argument count for " +
string(isStructConstructorCall ? "struct constructor" : "function call") +
": " +
toString(arguments.size()) +
" arguments given but expected " +
toString(parameterTypes.size()) +
".";
// Extend error message in case we try to construct a struct with mapping member.
if (_functionCall.annotation().kind == FunctionCallKind::StructConstructorCall && !membersRemovedForStructConstructor.empty())
{
msg += " Members that have to be skipped in memory:";
for (auto const& member: membersRemovedForStructConstructor)
msg += " " + member;
}
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())
msg += " This function requires a single bytes argument. Use \"\" as argument to provide empty calldata.";
else
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
)
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.";
m_errorReporter.typeError(_functionCall.location(), msg);
}
else if (isPositionalCall)
{
for (size_t i = 0; i < arguments.size(); ++i)
{
auto const& argType = type(*arguments[i]);
if (functionType->takesArbitraryParameters() && i >= parameterTypes.size())
{
bool errored = false;
if (auto t = dynamic_cast<RationalNumberType const*>(argType.get()))
if (!t->mobileType())
{
m_errorReporter.typeError(arguments[i]->location(), "Invalid rational number (too large or division by zero).");
errored = true;
}
if (!errored && !argType->fullEncodingType(false, abiEncoderV2, !functionType->padArguments()))
m_errorReporter.typeError(arguments[i]->location(), "This type cannot be encoded.");
}
else if (!type(*arguments[i])->isImplicitlyConvertibleTo(*parameterTypes[i]))
{
string msg =
"Invalid type for argument in function call. "
"Invalid implicit conversion from " +
type(*arguments[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
)
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
)
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.";
m_errorReporter.typeError(arguments[i]->location(), msg);
}
}
}
else
{
// call by named arguments
auto const& parameterNames = functionType->parameterNames();
if (functionType->takesArbitraryParameters())
m_errorReporter.typeError(
_functionCall.location(),
"Named arguments cannot be used for functions that take arbitrary parameters."
);
else if (parameterNames.size() > argumentNames.size())
m_errorReporter.typeError(_functionCall.location(), "Some argument names are missing.");
else if (parameterNames.size() < argumentNames.size())
m_errorReporter.typeError(_functionCall.location(), "Too many arguments.");
else
{
// check duplicate 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(arguments[i]->location(), "Duplicate named argument.");
}
// check actual types
if (!duplication)
for (size_t i = 0; i < argumentNames.size(); i++)
{
bool found = false;
for (size_t j = 0; j < parameterNames.size(); j++)
if (parameterNames[j] == *argumentNames[i])
{
found = true;
// check type convertible
if (!type(*arguments[i])->isImplicitlyConvertibleTo(*parameterTypes[j]))
m_errorReporter.typeError(
arguments[i]->location(),
"Invalid type for argument in function call. "
"Invalid implicit conversion from " +
type(*arguments[i])->toString() +
" to " +
parameterTypes[i]->toString() +
" requested."
);
break;
}
if (!found)
m_errorReporter.typeError(
_functionCall.location(),
"Named argument \"" + *argumentNames[i] + "\" does not match function declaration."
);
}
}
}
return false;
}
void TypeChecker::endVisit(NewExpression const& _newExpression)
{
TypePointer type = _newExpression.typeName().annotation().type;
solAssert(!!type, "Type name not resolved.");
if (auto contractName = dynamic_cast<UserDefinedTypeName const*>(&_newExpression.typeName()))
{
auto contract = dynamic_cast<ContractDefinition const*>(&dereference(*contractName));
if (!contract)
m_errorReporter.fatalTypeError(_newExpression.location(), "Identifier is not a contract.");
if (contract->contractKind() == ContractDefinition::ContractKind::Interface)
m_errorReporter.fatalTypeError(_newExpression.location(), "Cannot instantiate an interface.");
if (!contract->annotation().unimplementedFunctions.empty())
{
SecondarySourceLocation ssl;
for (auto function: contract->annotation().unimplementedFunctions)
ssl.append("Missing implementation:", function->location());
string msg = "Trying to create an instance of an abstract contract.";
ssl.limitSize(msg);
m_errorReporter.typeError(
_newExpression.location(),
ssl,
msg
);
}
if (!contract->constructorIsPublic())
m_errorReporter.typeError(_newExpression.location(), "Contract with internal constructor cannot be created directly.");
solAssert(!!m_scope, "");
m_scope->annotation().contractDependencies.insert(contract);
solAssert(
!contract->annotation().linearizedBaseContracts.empty(),
"Linearized base contracts not yet available."
);
if (contractDependenciesAreCyclic(*m_scope))
m_errorReporter.typeError(
_newExpression.location(),
"Circular reference for contract creation (cannot create instance of derived or same contract)."
);
_newExpression.annotation().type = FunctionType::newExpressionType(*contract);
}
else if (type->category() == Type::Category::Array)
{
if (!type->canLiveOutsideStorage())
m_errorReporter.fatalTypeError(
_newExpression.typeName().location(),
"Type cannot live outside storage."
);
if (!type->isDynamicallySized())
m_errorReporter.typeError(
_newExpression.typeName().location(),
"Length has to be placed in parentheses after the array type for new expression."
);
type = ReferenceType::copyForLocationIfReference(DataLocation::Memory, type);
_newExpression.annotation().type = make_shared<FunctionType>(
TypePointers{make_shared<IntegerType>(256)},
TypePointers{type},
strings(),
strings(),
FunctionType::Kind::ObjectCreation,
false,
StateMutability::Pure
);
_newExpression.annotation().isPure = true;
}
else
m_errorReporter.fatalTypeError(_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();
// Retrieve the types of the arguments if this is used to call a function.
auto const& argumentTypes = _memberAccess.annotation().argumentTypes;
MemberList::MemberMap possibleMembers = exprType->members(m_scope).membersByName(memberName);
size_t const initialMemberCount = possibleMembers.size();
if (initialMemberCount > 1 && argumentTypes)
{
// do overload resolution
for (auto it = possibleMembers.begin(); it != possibleMembers.end();)
if (
it->type->category() == Type::Category::Function &&
!dynamic_cast<FunctionType const&>(*it->type).canTakeArguments(*argumentTypes, exprType)
)
it = possibleMembers.erase(it);
else
++it;
}
auto& annotation = _memberAccess.annotation();
if (possibleMembers.size() == 0)
{
if (initialMemberCount == 0)
{
// Try to see if the member was removed because it is only available for storage types.
auto storageType = ReferenceType::copyForLocationIfReference(
DataLocation::Storage,
exprType
);
if (!storageType->members(m_scope).membersByName(memberName).empty())
m_errorReporter.fatalTypeError(
_memberAccess.location(),
"Member \"" + memberName + "\" is not available in " +
exprType->toString() +
" outside of storage."
);
}
string errorMsg = "Member \"" + memberName + "\" not found or not visible "
"after argument-dependent lookup in " + exprType->toString() +
(memberName == "value" ? " - did you forget the \"payable\" modifier?" : ".");
if (exprType->category() == Type::Category::Contract)
for (auto const& addressMember: IntegerType(160, IntegerType::Modifier::Address).nativeMembers(nullptr))
if (addressMember.name == memberName)
{
Identifier const* var = dynamic_cast<Identifier const*>(&_memberAccess.expression());
string varName = var ? var->name() : "...";
errorMsg += " Use \"address(" + varName + ")." + memberName + "\" to access this address member.";
break;
}
m_errorReporter.fatalTypeError(
_memberAccess.location(),
errorMsg
);
}
else if (possibleMembers.size() > 1)
m_errorReporter.fatalTypeError(
_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;
if (auto funType = dynamic_cast<FunctionType const*>(annotation.type.get()))
if (funType->bound() && !exprType->isImplicitlyConvertibleTo(*funType->selfType()))
m_errorReporter.typeError(
_memberAccess.location(),
"Function \"" + memberName + "\" cannot be called on an object of type " +
exprType->toString() + " (expected " + funType->selfType()->toString() + ")."
);
if (exprType->category() == Type::Category::Struct)
annotation.isLValue = true;
else if (exprType->category() == Type::Category::Array)
{
auto const& arrayType(dynamic_cast<ArrayType const&>(*exprType));
annotation.isLValue = (
memberName == "length" &&
arrayType.location() == DataLocation::Storage &&
arrayType.isDynamicallySized()
);
}
else if (exprType->category() == Type::Category::FixedBytes)
annotation.isLValue = false;
else if (TypeType const* typeType = dynamic_cast<decltype(typeType)>(exprType.get()))
{
if (ContractType const* contractType = dynamic_cast<decltype(contractType)>(typeType->actualType().get()))
annotation.isLValue = annotation.referencedDeclaration->isLValue();
}
if (exprType->category() == Type::Category::Contract)
{
// Warn about using send or transfer with a non-payable fallback function.
if (auto callType = dynamic_cast<FunctionType const*>(type(_memberAccess).get()))
{
auto kind = callType->kind();
auto contractType = dynamic_cast<ContractType const*>(exprType.get());
solAssert(!!contractType, "Should be contract type.");
if (
(kind == FunctionType::Kind::Send || kind == FunctionType::Kind::Transfer) &&
!contractType->isPayable()
)
m_errorReporter.typeError(
_memberAccess.location(),
"Value transfer to a contract without a payable fallback function."
);
}
}
// 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<TypeType const*>(exprType.get()))
if (tt->actualType()->category() == Type::Category::Enum)
annotation.isPure = true;
if (auto magicType = dynamic_cast<MagicType const*>(exprType.get()))
if (magicType->kind() == MagicType::Kind::ABI)
annotation.isPure = true;
return false;
}
bool TypeChecker::visit(IndexAccess const& _access)
{
_access.baseExpression().accept(*this);
TypePointer baseType = type(_access.baseExpression());
TypePointer resultType;
bool isLValue = false;
bool isPure = _access.baseExpression().annotation().isPure;
Expression const* index = _access.indexExpression();
switch (baseType->category())
{
case Type::Category::Array:
{
ArrayType const& actualType = dynamic_cast<ArrayType const&>(*baseType);
if (!index)
m_errorReporter.typeError(_access.location(), "Index expression cannot be omitted.");
else if (actualType.isString())
{
m_errorReporter.typeError(_access.location(), "Index access for string is not possible.");
index->accept(*this);
}
else
{
expectType(*index, IntegerType(256));
if (auto numberType = dynamic_cast<RationalNumberType const*>(type(*index).get()))
{
if (!numberType->isFractional()) // error is reported above
if (!actualType.isDynamicallySized() && actualType.length() <= numberType->literalValue(nullptr))
m_errorReporter.typeError(_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<MappingType const&>(*baseType);
if (!index)
m_errorReporter.typeError(_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<TypeType const&>(*baseType);
if (!index)
resultType = make_shared<TypeType>(make_shared<ArrayType>(DataLocation::Memory, typeType.actualType()));
else
{
expectType(*index, IntegerType(256));
if (auto length = dynamic_cast<RationalNumberType const*>(type(*index).get()))
resultType = make_shared<TypeType>(make_shared<ArrayType>(
DataLocation::Memory,
typeType.actualType(),
length->literalValue(nullptr)
));
else
m_errorReporter.fatalTypeError(index->location(), "Integer constant expected.");
}
break;
}
case Type::Category::FixedBytes:
{
FixedBytesType const& bytesType = dynamic_cast<FixedBytesType const&>(*baseType);
if (!index)
m_errorReporter.typeError(_access.location(), "Index expression cannot be omitted.");
else
{
expectType(*index, IntegerType(256));
if (auto integerType = dynamic_cast<RationalNumberType const*>(type(*index).get()))
if (bytesType.numBytes() <= integerType->literalValue(nullptr))
m_errorReporter.typeError(_access.location(), "Out of bounds array access.");
}
resultType = make_shared<FixedBytesType>(1);
isLValue = false; // @todo this heavily depends on how it is embedded
break;
}
default:
m_errorReporter.fatalTypeError(
_access.baseExpression().location(),
"Indexed expression has to be a type, mapping or array (is " + baseType->toString() + ")"
);
}
_access.annotation().type = move(resultType);
_access.annotation().isLValue = isLValue;
if (index && !index->annotation().isPure)
isPure = false;
_access.annotation().isPure = isPure;
return false;
}
bool TypeChecker::visit(Identifier const& _identifier)
{
IdentifierAnnotation& annotation = _identifier.annotation();
if (!annotation.referencedDeclaration)
{
if (!annotation.argumentTypes)
{
// The identifier should be a public state variable shadowing other functions
vector<Declaration const*> candidates;
for (Declaration const* declaration: annotation.overloadedDeclarations)
{
if (VariableDeclaration const* variableDeclaration = dynamic_cast<decltype(variableDeclaration)>(declaration))
candidates.push_back(declaration);
}
if (candidates.empty())
m_errorReporter.fatalTypeError(_identifier.location(), "No matching declaration found after variable lookup.");
else if (candidates.size() == 1)
annotation.referencedDeclaration = candidates.front();
else
m_errorReporter.fatalTypeError(_identifier.location(), "No unique declaration found after variable lookup.");
}
else if (annotation.overloadedDeclarations.empty())
m_errorReporter.fatalTypeError(_identifier.location(), "No candidates for overload resolution found.");
else if (annotation.overloadedDeclarations.size() == 1)
annotation.referencedDeclaration = *annotation.overloadedDeclarations.begin();
else
{
vector<Declaration const*> candidates;
for (Declaration const* declaration: annotation.overloadedDeclarations)
{
FunctionTypePointer functionType = declaration->functionType(true);
solAssert(!!functionType, "Requested type not present.");
if (functionType->canTakeArguments(*annotation.argumentTypes))
candidates.push_back(declaration);
}
if (candidates.empty())
m_errorReporter.fatalTypeError(_identifier.location(), "No matching declaration found after argument-dependent lookup.");
else if (candidates.size() == 1)
annotation.referencedDeclaration = candidates.front();
else
m_errorReporter.fatalTypeError(_identifier.location(), "No unique declaration found after argument-dependent lookup.");
}
}
solAssert(
!!annotation.referencedDeclaration,
"Referenced declaration is null after overload resolution."
);
annotation.isLValue = annotation.referencedDeclaration->isLValue();
annotation.type = annotation.referencedDeclaration->type();
if (!annotation.type)
m_errorReporter.fatalTypeError(_identifier.location(), "Declaration referenced before type could be determined.");
if (auto variableDeclaration = dynamic_cast<VariableDeclaration const*>(annotation.referencedDeclaration))
annotation.isPure = annotation.isConstant = variableDeclaration->isConstant();
else if (dynamic_cast<MagicVariableDeclaration const*>(annotation.referencedDeclaration))
if (dynamic_cast<FunctionType const*>(annotation.type.get()))
annotation.isPure = true;
return false;
}
void TypeChecker::endVisit(ElementaryTypeNameExpression const& _expr)
{
_expr.annotation().type = make_shared<TypeType>(Type::fromElementaryTypeName(_expr.typeName()));
_expr.annotation().isPure = true;
}
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 = make_shared<IntegerType>(160, IntegerType::Modifier::Address);
string msg;
if (_literal.value().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.value().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(
_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(
_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(
_literal.location(),
"Using \"years\" as a unit denomination is deprecated."
);
if (!_literal.annotation().type)
_literal.annotation().type = Type::forLiteral(_literal);
if (!_literal.annotation().type)
m_errorReporter.fatalTypeError(_literal.location(), "Invalid literal value.");
_literal.annotation().isPure = true;
}
bool TypeChecker::contractDependenciesAreCyclic(
ContractDefinition const& _contract,
std::set<ContractDefinition const*> const& _seenContracts
) const
{
// Naive depth-first search that remembers nodes already seen.
if (_seenContracts.count(&_contract))
return true;
set<ContractDefinition const*> 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;
}
void TypeChecker::expectType(Expression const& _expression, Type const& _expectedType)
{
_expression.accept(*this);
if (!type(_expression)->isImplicitlyConvertibleTo(_expectedType))
{
if (
type(_expression)->category() == Type::Category::RationalNumber &&
dynamic_pointer_cast<RationalNumberType const>(type(_expression))->isFractional() &&
type(_expression)->mobileType()
)
m_errorReporter.typeError(
_expression.location(),
"Type " +
type(_expression)->toString() +
" is not implicitly convertible to expected type " +
_expectedType.toString() +
". Try converting to type " +
type(_expression)->mobileType()->toString() +
" or use an explicit conversion."
);
else
m_errorReporter.typeError(
_expression.location(),
"Type " +
type(_expression)->toString() +
" is not implicitly convertible to expected type " +
_expectedType.toString() +
"."
);
}
}
void TypeChecker::requireLValue(Expression const& _expression)
{
_expression.annotation().lValueRequested = true;
_expression.accept(*this);
if (_expression.annotation().isConstant)
m_errorReporter.typeError(_expression.location(), "Cannot assign to a constant variable.");
else if (!_expression.annotation().isLValue)
m_errorReporter.typeError(_expression.location(), "Expression has to be an lvalue.");
}