void RefCountedCopyConstructorChecker::registerMatchers(MatchFinder* AstMatcher) {
AstMatcher->addMatcher(
cxxConstructExpr(
hasDeclaration(cxxConstructorDecl(isCompilerProvidedCopyConstructor(),
ofClass(hasRefCntMember()))))
.bind("node"),
this);
}
/// \brief Creates a matcher that finds the \c std::auto_ptr copy-ctor and
/// assign-operator expressions.
///
/// \c AutoPtrOwnershipTransferId is assigned to the argument of the expression,
/// this is the part that has to be wrapped by \c std::move().
///
/// \code
/// std::auto_ptr<int> i, j;
/// i = j;
/// ~~~~^
/// \endcode
StatementMatcher makeTransferOwnershipExprMatcher() {
return anyOf(
cxxOperatorCallExpr(allOf(hasOverloadedOperatorName("="),
callee(cxxMethodDecl(ofClass(AutoPtrDecl))),
hasArgument(1, MovableArgumentMatcher))),
cxxConstructExpr(allOf(hasType(AutoPtrType), argumentCountIs(1),
hasArgument(0, MovableArgumentMatcher))));
}
void SlicingCheck::registerMatchers(MatchFinder *Finder) {
// When we see:
// class B : public A { ... };
// A a;
// B b;
// a = b;
// The assignment is OK if:
// - the assignment operator is defined as taking a B as second parameter,
// or
// - B does not define any additional members (either variables or
// overrides) wrt A.
//
// The same holds for copy ctor calls. This also captures stuff like:
// void f(A a);
// f(b);
// Helpers.
const auto OfBaseClass = ofClass(cxxRecordDecl().bind("BaseDecl"));
const auto IsDerivedFromBaseDecl =
cxxRecordDecl(isDerivedFrom(equalsBoundNode("BaseDecl")))
.bind("DerivedDecl");
const auto HasTypeDerivedFromBaseDecl =
anyOf(hasType(IsDerivedFromBaseDecl),
hasType(references(IsDerivedFromBaseDecl)));
const auto IsWithinDerivedCtor =
hasParent(cxxConstructorDecl(ofClass(equalsBoundNode("DerivedDecl"))));
// Assignement slicing: "a = b;" and "a = std::move(b);" variants.
const auto SlicesObjectInAssignment =
callExpr(callee(cxxMethodDecl(anyOf(isCopyAssignmentOperator(),
isMoveAssignmentOperator()),
OfBaseClass)),
hasArgument(1, HasTypeDerivedFromBaseDecl));
// Construction slicing: "A a{b};" and "f(b);" variants. Note that in case of
// slicing the letter will create a temporary and therefore call a ctor.
const auto SlicesObjectInCtor = cxxConstructExpr(
hasDeclaration(cxxConstructorDecl(
anyOf(isCopyConstructor(), isMoveConstructor()), OfBaseClass)),
hasArgument(0, HasTypeDerivedFromBaseDecl),
// We need to disable matching on the call to the base copy/move
// constructor in DerivedDecl's constructors.
unless(IsWithinDerivedCtor));
Finder->addMatcher(
expr(anyOf(SlicesObjectInAssignment, SlicesObjectInCtor)).bind("Call"),
this);
}
void AssignOperatorSignatureCheck::registerMatchers(
ast_matchers::MatchFinder *Finder) {
// Only register the matchers for C++; the functionality currently does not
// provide any benefit to other languages, despite being benign.
if (getLangOpts().CPlusPlus) {
const auto HasGoodReturnType = methodDecl(returns(lValueReferenceType(
pointee(unless(isConstQualified()),
hasDeclaration(equalsBoundNode("class"))))));
const auto IsSelf = qualType(anyOf(
hasDeclaration(equalsBoundNode("class")),
referenceType(pointee(hasDeclaration(equalsBoundNode("class"))))));
const auto IsSelfAssign =
methodDecl(unless(anyOf(isDeleted(), isPrivate(), isImplicit())),
hasName("operator="), ofClass(recordDecl().bind("class")),
hasParameter(0, parmVarDecl(hasType(IsSelf))))
.bind("method");
Finder->addMatcher(
methodDecl(IsSelfAssign, unless(HasGoodReturnType)).bind("ReturnType"),
this);
const auto BadSelf = referenceType(
anyOf(lValueReferenceType(pointee(unless(isConstQualified()))),
rValueReferenceType(pointee(isConstQualified()))));
Finder->addMatcher(
methodDecl(IsSelfAssign, hasParameter(0, parmVarDecl(hasType(BadSelf))))
.bind("ArgumentType"),
this);
Finder->addMatcher(methodDecl(IsSelfAssign, isConst()).bind("Const"), this);
}
}
TEST(FriendDecl, FriendConstructorDestructorRange) {
const std::string Code = "struct B {\n"
"B();\n"
"~B();\n"
"};\n"
"struct A {\n"
"friend B::B(), B::~B();\n"
"};\n";
RangeVerifier<FriendDecl> ConstructorVerifier;
ConstructorVerifier.expectRange(6, 1, 6, 13);
EXPECT_TRUE(ConstructorVerifier.match(
Code, friendDecl(has(constructorDecl(ofClass(hasName("B")))))));
RangeVerifier<FriendDecl> DestructorVerifier;
DestructorVerifier.expectRange(6, 1, 6, 22);
EXPECT_TRUE(DestructorVerifier.match(
Code, friendDecl(has(destructorDecl(ofClass(hasName("B")))))));
}
TEST(FriendDecl, FriendConstructorDestructorLocation) {
const std::string Code = "struct B {\n"
"B();\n"
"~B();\n"
"};\n"
"struct A {\n"
"friend B::B(), B::~B();\n"
"};\n";
LocationVerifier<FriendDecl> ConstructorVerifier;
ConstructorVerifier.expectLocation(6, 11);
EXPECT_TRUE(ConstructorVerifier.match(
Code, friendDecl(has(constructorDecl(ofClass(hasName("B")))))));
LocationVerifier<FriendDecl> DestructorVerifier;
DestructorVerifier.expectLocation(6, 19);
EXPECT_TRUE(DestructorVerifier.match(
Code, friendDecl(has(destructorDecl(ofClass(hasName("B")))))));
}
void ExplicitImplicitChecker::registerMatchers(MatchFinder* AstMatcher) {
AstMatcher->addMatcher(cxxConstructorDecl(isInterestingImplicitCtor(),
ofClass(allOf(isConcreteClass(),
decl().bind("class"))),
unless(isMarkedImplicit()))
.bind("ctor"),
this);
}
void UniqueptrResetReleaseCheck::registerMatchers(MatchFinder *Finder) {
// Only register the matchers for C++11; the functionality currently does not
// provide any benefit to other languages, despite being benign.
if (!getLangOpts().CPlusPlus11)
return;
Finder->addMatcher(
memberCallExpr(
on(expr().bind("left")), callee(memberExpr().bind("reset_member")),
callee(methodDecl(hasName("reset"),
ofClass(recordDecl(hasName("::std::unique_ptr"),
decl().bind("left_class"))))),
has(memberCallExpr(
on(expr().bind("right")),
callee(memberExpr().bind("release_member")),
callee(methodDecl(
hasName("release"),
ofClass(recordDecl(hasName("::std::unique_ptr"),
decl().bind("right_class"))))))))
.bind("reset_call"),
this);
}
void UnconventionalAssignOperatorCheck::registerMatchers(
ast_matchers::MatchFinder *Finder) {
// Only register the matchers for C++; the functionality currently does not
// provide any benefit to other languages, despite being benign.
if (!getLangOpts().CPlusPlus)
return;
const auto HasGoodReturnType = cxxMethodDecl(returns(lValueReferenceType(
pointee(unless(isConstQualified()),
anyOf(autoType(), hasDeclaration(equalsBoundNode("class")))))));
const auto IsSelf = qualType(
anyOf(hasDeclaration(equalsBoundNode("class")),
referenceType(pointee(hasDeclaration(equalsBoundNode("class"))))));
const auto IsAssign =
cxxMethodDecl(unless(anyOf(isDeleted(), isPrivate(), isImplicit())),
hasName("operator="), ofClass(recordDecl().bind("class")))
.bind("method");
const auto IsSelfAssign =
cxxMethodDecl(IsAssign, hasParameter(0, parmVarDecl(hasType(IsSelf))))
.bind("method");
Finder->addMatcher(
cxxMethodDecl(IsAssign, unless(HasGoodReturnType)).bind("ReturnType"),
this);
const auto BadSelf = referenceType(
anyOf(lValueReferenceType(pointee(unless(isConstQualified()))),
rValueReferenceType(pointee(isConstQualified()))));
Finder->addMatcher(
cxxMethodDecl(IsSelfAssign,
hasParameter(0, parmVarDecl(hasType(BadSelf))))
.bind("ArgumentType"),
this);
Finder->addMatcher(
cxxMethodDecl(IsSelfAssign, anyOf(isConst(), isVirtual())).bind("cv"),
this);
const auto IsBadReturnStatement = returnStmt(unless(has(ignoringParenImpCasts(
anyOf(unaryOperator(hasOperatorName("*"), hasUnaryOperand(cxxThisExpr())),
cxxOperatorCallExpr(argumentCountIs(1),
callee(unresolvedLookupExpr()),
hasArgument(0, cxxThisExpr())))))));
const auto IsGoodAssign = cxxMethodDecl(IsAssign, HasGoodReturnType);
Finder->addMatcher(returnStmt(IsBadReturnStatement, forFunction(IsGoodAssign))
.bind("returnStmt"),
this);
}
void UndelegatedConstructorCheck::registerMatchers(MatchFinder *Finder) {
// We look for calls to constructors of the same type in constructors. To do
// this we have to look through a variety of nodes that occur in the path,
// depending on the type's destructor and the number of arguments on the
// constructor call, this is handled by ignoringTemporaryExpr. Ignore template
// instantiations to reduce the number of duplicated warnings.
//
// Only register the matchers for C++11; the functionality currently does not
// provide any benefit to other languages, despite being benign.
if (!getLangOpts().CPlusPlus11)
return;
Finder->addMatcher(
compoundStmt(
hasParent(
cxxConstructorDecl(ofClass(cxxRecordDecl().bind("parent")))),
forEach(ignoringTemporaryExpr(
cxxConstructExpr(hasDeclaration(cxxConstructorDecl(ofClass(
cxxRecordDecl(baseOfBoundNode("parent"))))))
.bind("construct"))),
unless(isInTemplateInstantiation())),
this);
}
void UseEmplaceCheck::registerMatchers(MatchFinder *Finder) {
if (!getLangOpts().CPlusPlus11)
return;
// FIXME: Bunch of functionality that could be easily added:
// + add handling of `push_front` for std::forward_list, std::list
// and std::deque.
// + add handling of `push` for std::stack, std::queue, std::priority_queue
// + add handling of `insert` for stl associative container, but be careful
// because this requires special treatment (it could cause performance
// regression)
// + match for emplace calls that should be replaced with insertion
// + match for make_pair calls.
auto callPushBack = cxxMemberCallExpr(
hasDeclaration(functionDecl(hasName("push_back"))),
on(hasType(cxxRecordDecl(hasAnyName("std::vector", "llvm::SmallVector",
"std::list", "std::deque")))));
// We can't replace push_backs of smart pointer because
// if emplacement fails (f.e. bad_alloc in vector) we will have leak of
// passed pointer because smart pointer won't be constructed
// (and destructed) as in push_back case.
auto isCtorOfSmartPtr = hasDeclaration(cxxConstructorDecl(
ofClass(hasAnyName("std::shared_ptr", "std::unique_ptr", "std::auto_ptr",
"std::weak_ptr"))));
// Bitfields binds only to consts and emplace_back take it by universal ref.
auto bitFieldAsArgument = hasAnyArgument(ignoringParenImpCasts(
memberExpr(hasDeclaration(fieldDecl(matchers::isBitfield())))));
// We could have leak of resource.
auto newExprAsArgument = hasAnyArgument(ignoringParenImpCasts(cxxNewExpr()));
auto constructingDerived =
hasParent(implicitCastExpr(hasCastKind(CastKind::CK_DerivedToBase)));
auto hasInitList = has(ignoringParenImpCasts(initListExpr()));
auto soughtConstructExpr =
cxxConstructExpr(
unless(anyOf(isCtorOfSmartPtr, hasInitList, bitFieldAsArgument,
newExprAsArgument, constructingDerived,
has(materializeTemporaryExpr(hasInitList)))))
.bind("ctor");
auto hasConstructExpr = has(ignoringParenImpCasts(soughtConstructExpr));
auto ctorAsArgument = materializeTemporaryExpr(
anyOf(hasConstructExpr, has(cxxFunctionalCastExpr(hasConstructExpr))));
Finder->addMatcher(
cxxMemberCallExpr(callPushBack, has(ctorAsArgument)).bind("call"), this);
}
void ReplaceAutoPtrCheck::registerMatchers(MatchFinder *Finder) {
// Only register the matchers for C++; the functionality currently does not
// provide any benefit to other languages, despite being benign.
if (!getLangOpts().CPlusPlus)
return;
auto AutoPtrDecl = recordDecl(hasName("auto_ptr"), isFromStdNamespace());
auto AutoPtrType = qualType(hasDeclaration(AutoPtrDecl));
// std::auto_ptr<int> a;
// ^~~~~~~~~~~~~
//
// typedef std::auto_ptr<int> int_ptr_t;
// ^~~~~~~~~~~~~
//
// std::auto_ptr<int> fn(std::auto_ptr<int>);
// ^~~~~~~~~~~~~ ^~~~~~~~~~~~~
Finder->addMatcher(typeLoc(loc(qualType(AutoPtrType,
// Skip elaboratedType() as the named
// type will match soon thereafter.
unless(elaboratedType()))))
.bind(AutoPtrTokenId),
this);
// using std::auto_ptr;
// ^~~~~~~~~~~~~~~~~~~
Finder->addMatcher(usingDecl(hasAnyUsingShadowDecl(hasTargetDecl(allOf(
hasName("auto_ptr"), isFromStdNamespace()))))
.bind(AutoPtrTokenId),
this);
// Find ownership transfers via copy construction and assignment.
// AutoPtrOwnershipTransferId is bound to the the part that has to be wrapped
// into std::move().
// std::auto_ptr<int> i, j;
// i = j;
// ~~~~^
auto MovableArgumentMatcher =
expr(isLValue(), hasType(AutoPtrType)).bind(AutoPtrOwnershipTransferId);
Finder->addMatcher(
cxxOperatorCallExpr(hasOverloadedOperatorName("="),
callee(cxxMethodDecl(ofClass(AutoPtrDecl))),
hasArgument(1, MovableArgumentMatcher)),
this);
Finder->addMatcher(cxxConstructExpr(hasType(AutoPtrType), argumentCountIs(1),
hasArgument(0, MovableArgumentMatcher)),
this);
}
void AvoidConstParamsInDecls::registerMatchers(MatchFinder *Finder) {
const auto ConstParamDecl =
parmVarDecl(hasType(qualType(isConstQualified()))).bind("param");
Finder->addMatcher(
functionDecl(unless(isDefinition()),
// Lambdas are always their own definition, but they
// generate a non-definition FunctionDecl too. Ignore those.
// Class template instantiations have a non-definition
// CXXMethodDecl for methods that aren't used in this
// translation unit. Ignore those, as the template will have
// already been checked.
unless(cxxMethodDecl(ofClass(cxxRecordDecl(anyOf(
isLambda(), ast_matchers::isTemplateInstantiation()))))),
has(typeLoc(forEach(ConstParamDecl))))
.bind("func"),
this);
}
void StringIntegerAssignmentCheck::registerMatchers(MatchFinder *Finder) {
if (!getLangOpts().CPlusPlus)
return;
Finder->addMatcher(
cxxOperatorCallExpr(
anyOf(hasOverloadedOperatorName("="),
hasOverloadedOperatorName("+=")),
callee(cxxMethodDecl(ofClass(classTemplateSpecializationDecl(
hasName("::std::basic_string"),
hasTemplateArgument(0, refersToType(qualType().bind("type"))))))),
hasArgument(1,
ignoringImpCasts(expr(hasType(isInteger()),
unless(hasType(isAnyCharacter())))
.bind("expr"))),
unless(isInTemplateInstantiation())),
this);
}
void RedundantMemberInitCheck::registerMatchers(MatchFinder *Finder) {
auto Construct =
cxxConstructExpr(
hasDeclaration(cxxConstructorDecl(hasParent(
cxxRecordDecl(unless(isTriviallyDefaultConstructible()))))))
.bind("construct");
Finder->addMatcher(
cxxConstructorDecl(
unless(isDelegatingConstructor()),
ofClass(unless(
anyOf(isUnion(), ast_matchers::isTemplateInstantiation()))),
forEachConstructorInitializer(
cxxCtorInitializer(isWritten(),
withInitializer(ignoringImplicit(Construct)),
unless(forField(hasType(isConstQualified()))))
.bind("init"))),
this);
}
void UpgradeDurationConversionsCheck::registerMatchers(MatchFinder *Finder) {
if (!getLangOpts().CPlusPlus)
return;
// For the arithmetic calls, we match only the uses of the templated operators
// where the template parameter is not a built-in type. This means the
// instantiation makes use of an available user defined conversion to
// `int64_t`.
//
// The implementation of these templates will be updated to fail SFINAE for
// non-integral types. We match them to suggest an explicit cast.
// Match expressions like `a *= b` and `a /= b` where `a` has type
// `absl::Duration` and `b` is not of a built-in type.
Finder->addMatcher(
cxxOperatorCallExpr(
argumentCountIs(2),
hasArgument(
0, expr(hasType(cxxRecordDecl(hasName("::absl::Duration"))))),
hasArgument(1, expr().bind("arg")),
callee(functionDecl(
hasParent(functionTemplateDecl()),
unless(hasTemplateArgument(0, refersToType(builtinType()))),
hasAnyName("operator*=", "operator/=")))),
this);
// Match expressions like `a.operator*=(b)` and `a.operator/=(b)` where `a`
// has type `absl::Duration` and `b` is not of a built-in type.
Finder->addMatcher(
cxxMemberCallExpr(
callee(cxxMethodDecl(
ofClass(cxxRecordDecl(hasName("::absl::Duration"))),
hasParent(functionTemplateDecl()),
unless(hasTemplateArgument(0, refersToType(builtinType()))),
hasAnyName("operator*=", "operator/="))),
argumentCountIs(1), hasArgument(0, expr().bind("arg"))),
this);
// Match expressions like `a * b`, `a / b`, `operator*(a, b)`, and
// `operator/(a, b)` where `a` has type `absl::Duration` and `b` is not of a
// built-in type.
Finder->addMatcher(
callExpr(callee(functionDecl(
hasParent(functionTemplateDecl()),
unless(hasTemplateArgument(0, refersToType(builtinType()))),
hasAnyName("::absl::operator*", "::absl::operator/"))),
argumentCountIs(2),
hasArgument(0, expr(hasType(
cxxRecordDecl(hasName("::absl::Duration"))))),
hasArgument(1, expr().bind("arg"))),
this);
// Match expressions like `a * b` and `operator*(a, b)` where `a` is not of a
// built-in type and `b` has type `absl::Duration`.
Finder->addMatcher(
callExpr(callee(functionDecl(
hasParent(functionTemplateDecl()),
unless(hasTemplateArgument(0, refersToType(builtinType()))),
hasName("::absl::operator*"))),
argumentCountIs(2), hasArgument(0, expr().bind("arg")),
hasArgument(1, expr(hasType(cxxRecordDecl(
hasName("::absl::Duration")))))),
this);
// For the factory functions, we match only the non-templated overloads that
// take an `int64_t` parameter. Within these calls, we care about implicit
// casts through a user defined conversion to `int64_t`.
//
// The factory functions will be updated to be templated and SFINAE on whether
// the template parameter is an integral type. This complements the already
// existing templated overloads that only accept floating point types.
// Match calls like:
// `absl::Nanoseconds(x)`
// `absl::Microseconds(x)`
// `absl::Milliseconds(x)`
// `absl::Seconds(x)`
// `absl::Minutes(x)`
// `absl::Hours(x)`
// where `x` is not of a built-in type.
Finder->addMatcher(
implicitCastExpr(
anyOf(hasCastKind(CK_UserDefinedConversion),
has(implicitCastExpr(hasCastKind(CK_UserDefinedConversion)))),
hasParent(callExpr(
callee(functionDecl(DurationFactoryFunction(),
unless(hasParent(functionTemplateDecl())))),
hasArgument(0, expr().bind("arg"))))),
this);
}
void UseEmplaceCheck::registerMatchers(MatchFinder *Finder) {
if (!getLangOpts().CPlusPlus11)
return;
// FIXME: Bunch of functionality that could be easily added:
// + add handling of `push_front` for std::forward_list, std::list
// and std::deque.
// + add handling of `push` for std::stack, std::queue, std::priority_queue
// + add handling of `insert` for stl associative container, but be careful
// because this requires special treatment (it could cause performance
// regression)
// + match for emplace calls that should be replaced with insertion
// + match for make_pair calls.
auto callPushBack = cxxMemberCallExpr(
hasDeclaration(functionDecl(hasName("push_back"))),
on(hasType(cxxRecordDecl(hasAnyName(SmallVector<StringRef, 5>(
ContainersWithPushBack.begin(), ContainersWithPushBack.end()))))));
// We can't replace push_backs of smart pointer because
// if emplacement fails (f.e. bad_alloc in vector) we will have leak of
// passed pointer because smart pointer won't be constructed
// (and destructed) as in push_back case.
auto isCtorOfSmartPtr = hasDeclaration(cxxConstructorDecl(ofClass(hasAnyName(
SmallVector<StringRef, 5>(SmartPointers.begin(), SmartPointers.end())))));
// Bitfields binds only to consts and emplace_back take it by universal ref.
auto bitFieldAsArgument = hasAnyArgument(
ignoringImplicit(memberExpr(hasDeclaration(fieldDecl(isBitField())))));
// Initializer list can't be passed to universal reference.
auto initializerListAsArgument = hasAnyArgument(
ignoringImplicit(cxxConstructExpr(isListInitialization())));
// We could have leak of resource.
auto newExprAsArgument = hasAnyArgument(ignoringImplicit(cxxNewExpr()));
// We would call another constructor.
auto constructingDerived =
hasParent(implicitCastExpr(hasCastKind(CastKind::CK_DerivedToBase)));
// emplace_back can't access private constructor.
auto isPrivateCtor = hasDeclaration(cxxConstructorDecl(isPrivate()));
auto hasInitList = has(ignoringImplicit(initListExpr()));
// FIXME: Discard 0/NULL (as nullptr), static inline const data members,
// overloaded functions and template names.
auto soughtConstructExpr =
cxxConstructExpr(
unless(anyOf(isCtorOfSmartPtr, hasInitList, bitFieldAsArgument,
initializerListAsArgument, newExprAsArgument,
constructingDerived, isPrivateCtor)))
.bind("ctor");
auto hasConstructExpr = has(ignoringImplicit(soughtConstructExpr));
auto ctorAsArgument = materializeTemporaryExpr(
anyOf(hasConstructExpr, has(cxxFunctionalCastExpr(hasConstructExpr))));
Finder->addMatcher(cxxMemberCallExpr(callPushBack, has(ctorAsArgument),
unless(isInTemplateInstantiation()))
.bind("call"),
this);
}