diff options
| -rw-r--r-- | Changelog.md | 1 | ||||
| -rw-r--r-- | libsolidity/analysis/PostTypeChecker.cpp | 108 | ||||
| -rw-r--r-- | libsolidity/analysis/PostTypeChecker.h | 69 | ||||
| -rw-r--r-- | libsolidity/analysis/StaticAnalyzer.h | 3 | ||||
| -rw-r--r-- | libsolidity/interface/CompilerStack.cpp | 9 | ||||
| -rw-r--r-- | test/libsolidity/SolidityNameAndTypeResolution.cpp | 49 |
6 files changed, 231 insertions, 8 deletions
diff --git a/Changelog.md b/Changelog.md index 5eb1e401..8e11775b 100644 --- a/Changelog.md +++ b/Changelog.md @@ -11,6 +11,7 @@ Bugfixes: * Commandline interface: Always escape filenames (replace ``/``, ``:`` and ``.`` with ``_``). * Commandline interface: Do not try creating paths ``.`` and ``..``. * Type system: Fix a crash caused by continuing on fatal errors in the code. + * Type system: Detect cyclic dependencies between constants. * Type system: Disallow arrays with negative length. * Type system: Fix a crash related to invalid binary operators. * Type system: Disallow ``var`` declaration with empty tuple type. diff --git a/libsolidity/analysis/PostTypeChecker.cpp b/libsolidity/analysis/PostTypeChecker.cpp new file mode 100644 index 00000000..cae77c74 --- /dev/null +++ b/libsolidity/analysis/PostTypeChecker.cpp @@ -0,0 +1,108 @@ +/* + 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/>. +*/ + +#include <libsolidity/analysis/PostTypeChecker.h> +#include <libsolidity/ast/AST.h> +#include <libsolidity/analysis/SemVerHandler.h> +#include <libsolidity/interface/Version.h> + +#include <boost/range/adaptor/map.hpp> + +#include <memory> + +using namespace std; +using namespace dev; +using namespace dev::solidity; + + +bool PostTypeChecker::check(ASTNode const& _astRoot) +{ + _astRoot.accept(*this); + return Error::containsOnlyWarnings(m_errors); +} + +void PostTypeChecker::typeError(SourceLocation const& _location, std::string const& _description) +{ + auto err = make_shared<Error>(Error::Type::TypeError); + *err << + errinfo_sourceLocation(_location) << + errinfo_comment(_description); + + m_errors.push_back(err); +} + +bool PostTypeChecker::visit(ContractDefinition const&) +{ + solAssert(!m_currentConstVariable, ""); + solAssert(m_constVariableDependencies.empty(), ""); + return true; +} + +void PostTypeChecker::endVisit(ContractDefinition const&) +{ + solAssert(!m_currentConstVariable, ""); + for (auto declaration: m_constVariables) + if (auto identifier = findCycle(declaration)) + typeError(declaration->location(), "The value of the constant " + declaration->name() + " has a cyclic dependency via " + identifier->name() + "."); +} + +bool PostTypeChecker::visit(VariableDeclaration const& _variable) +{ + solAssert(!m_currentConstVariable, ""); + if (_variable.isConstant()) + { + m_currentConstVariable = &_variable; + m_constVariables.push_back(&_variable); + } + return true; +} + +void PostTypeChecker::endVisit(VariableDeclaration const& _variable) +{ + if (_variable.isConstant()) + { + solAssert(m_currentConstVariable == &_variable, ""); + m_currentConstVariable = nullptr; + } +} + +bool PostTypeChecker::visit(Identifier const& _identifier) +{ + if (m_currentConstVariable) + if (auto var = dynamic_cast<VariableDeclaration const*>(_identifier.annotation().referencedDeclaration)) + if (var->isConstant()) + m_constVariableDependencies[m_currentConstVariable].insert(var); + return true; +} + +VariableDeclaration const* PostTypeChecker::findCycle( + VariableDeclaration const* _startingFrom, + set<VariableDeclaration const*> const& _seen +) +{ + if (_seen.count(_startingFrom)) + return _startingFrom; + else if (m_constVariableDependencies.count(_startingFrom)) + { + set<VariableDeclaration const*> seen(_seen); + seen.insert(_startingFrom); + for (auto v: m_constVariableDependencies[_startingFrom]) + if (findCycle(v, seen)) + return v; + } + return nullptr; +} diff --git a/libsolidity/analysis/PostTypeChecker.h b/libsolidity/analysis/PostTypeChecker.h new file mode 100644 index 00000000..8774f413 --- /dev/null +++ b/libsolidity/analysis/PostTypeChecker.h @@ -0,0 +1,69 @@ +/* + 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/>. +*/ + +#pragma once + +#include <libsolidity/analysis/TypeChecker.h> +#include <libsolidity/ast/Types.h> +#include <libsolidity/ast/ASTAnnotations.h> +#include <libsolidity/ast/ASTForward.h> +#include <libsolidity/ast/ASTVisitor.h> + +namespace dev +{ +namespace solidity +{ + +/** + * This module performs analyses on the AST that are done after type checking and assignments of types: + * - whether there are circular references in constant state variables + * @TODO factor out each use-case into an individual class (but do the traversal only once) + */ +class PostTypeChecker: private ASTConstVisitor +{ +public: + /// @param _errors the reference to the list of errors and warnings to add them found during type checking. + PostTypeChecker(ErrorList& _errors): m_errors(_errors) {} + + bool check(ASTNode const& _astRoot); + +private: + /// Adds a new error to the list of errors. + void typeError(SourceLocation const& _location, std::string const& _description); + + virtual bool visit(ContractDefinition const& _contract) override; + virtual void endVisit(ContractDefinition const& _contract) override; + + virtual bool visit(VariableDeclaration const& _declaration) override; + virtual void endVisit(VariableDeclaration const& _declaration) override; + + virtual bool visit(Identifier const& _identifier) override; + + VariableDeclaration const* findCycle( + VariableDeclaration const* _startingFrom, + std::set<VariableDeclaration const*> const& _seen = {} + ); + + ErrorList& m_errors; + + VariableDeclaration const* m_currentConstVariable = nullptr; + std::vector<VariableDeclaration const*> m_constVariables; ///< Required for determinism. + std::map<VariableDeclaration const*, std::set<VariableDeclaration const*>> m_constVariableDependencies; +}; + +} +} diff --git a/libsolidity/analysis/StaticAnalyzer.h b/libsolidity/analysis/StaticAnalyzer.h index b6cf783e..0cb961bd 100644 --- a/libsolidity/analysis/StaticAnalyzer.h +++ b/libsolidity/analysis/StaticAnalyzer.h @@ -36,6 +36,9 @@ namespace solidity /** * The module that performs static analysis on the AST. + * In this context, static analysis is anything that can produce warnings which can help + * programmers write cleaner code. For every warning generated eher, it has to be possible to write + * equivalent code that does generate the warning. */ class StaticAnalyzer: private ASTConstVisitor { diff --git a/libsolidity/interface/CompilerStack.cpp b/libsolidity/interface/CompilerStack.cpp index 9d8d872f..594efb1e 100644 --- a/libsolidity/interface/CompilerStack.cpp +++ b/libsolidity/interface/CompilerStack.cpp @@ -34,6 +34,7 @@ #include <libsolidity/analysis/TypeChecker.h> #include <libsolidity/analysis/DocStringAnalyser.h> #include <libsolidity/analysis/StaticAnalyzer.h> +#include <libsolidity/analysis/PostTypeChecker.h> #include <libsolidity/analysis/SyntaxChecker.h> #include <libsolidity/codegen/Compiler.h> #include <libsolidity/interface/InterfaceHandler.h> @@ -219,6 +220,14 @@ bool CompilerStack::parse() if (noErrors) { + PostTypeChecker postTypeChecker(m_errors); + for (Source const* source: m_sourceOrder) + if (!postTypeChecker.check(*source->ast)) + noErrors = false; + } + + if (noErrors) + { StaticAnalyzer staticAnalyzer(m_errors); for (Source const* source: m_sourceOrder) if (!staticAnalyzer.analyze(*source->ast)) diff --git a/test/libsolidity/SolidityNameAndTypeResolution.cpp b/test/libsolidity/SolidityNameAndTypeResolution.cpp index 02d81d14..3d82fc70 100644 --- a/test/libsolidity/SolidityNameAndTypeResolution.cpp +++ b/test/libsolidity/SolidityNameAndTypeResolution.cpp @@ -20,19 +20,23 @@ * Unit tests for the name and type resolution of the solidity parser. */ -#include <string> +#include <test/libsolidity/ErrorCheck.h> + +#include <test/TestHelper.h> -#include <libdevcore/SHA3.h> #include <libsolidity/parsing/Scanner.h> #include <libsolidity/parsing/Parser.h> #include <libsolidity/analysis/NameAndTypeResolver.h> #include <libsolidity/analysis/StaticAnalyzer.h> +#include <libsolidity/analysis/PostTypeChecker.h> #include <libsolidity/analysis/SyntaxChecker.h> #include <libsolidity/interface/Exceptions.h> #include <libsolidity/analysis/GlobalContext.h> #include <libsolidity/analysis/TypeChecker.h> -#include "../TestHelper.h" -#include "ErrorCheck.h" + +#include <libdevcore/SHA3.h> + +#include <string> using namespace std; @@ -93,10 +97,11 @@ parseAnalyseAndReturnError(string const& _source, bool _reportWarnings = false, BOOST_CHECK(success || !errors.empty()); } if (success) - { - StaticAnalyzer staticAnalyzer(errors); - staticAnalyzer.analyze(*sourceUnit); - } + if (!PostTypeChecker(errors).check(*sourceUnit)) + success = false; + if (success) + if (!StaticAnalyzer(errors).analyze(*sourceUnit)) + success = false; if (errors.size() > 1 && !_allowMultipleErrors) BOOST_FAIL("Multiple errors found"); for (auto const& currentError: errors) @@ -5180,6 +5185,34 @@ BOOST_AUTO_TEST_CASE(address_methods) CHECK_SUCCESS(text); } +BOOST_AUTO_TEST_CASE(cyclic_dependency_for_constants) +{ + char const* text = R"( + contract C { + uint constant a = a; + } + )"; + CHECK_ERROR(text, TypeError, "cyclic dependency via a"); + text = R"( + contract C { + uint constant a = b * c; + uint constant b = 7; + uint constant c = b + uint(sha3(d)); + uint constant d = 2 + a; + } + )"; + CHECK_ERROR_ALLOW_MULTI(text, TypeError, "a has a cyclic dependency via c"); + text = R"( + contract C { + uint constant a = b * c; + uint constant b = 7; + uint constant c = 4 + uint(sha3(d)); + uint constant d = 2 + b; + } + )"; + CHECK_SUCCESS(text); +} + BOOST_AUTO_TEST_SUITE_END() } |