void ShrinkToFitCheck::registerMatchers(MatchFinder *Finder) {
// Swap as a function need not to be considered, because rvalue can not
// be bound to a non-const reference.
const auto ShrinkableAsMember =
memberExpr(member(valueDecl().bind("ContainerDecl")));
const auto ShrinkableAsDecl =
declRefExpr(hasDeclaration(valueDecl().bind("ContainerDecl")));
const auto CopyCtorCall = constructExpr(
hasArgument(0, anyOf(ShrinkableAsMember, ShrinkableAsDecl,
unaryOperator(has(ShrinkableAsMember)),
unaryOperator(has(ShrinkableAsDecl)))));
const auto SwapParam = expr(anyOf(
memberExpr(member(equalsBoundNode("ContainerDecl"))),
declRefExpr(hasDeclaration(equalsBoundNode("ContainerDecl"))),
unaryOperator(has(memberExpr(member(equalsBoundNode("ContainerDecl"))))),
unaryOperator(
has(declRefExpr(hasDeclaration(equalsBoundNode("ContainerDecl")))))));
Finder->addMatcher(
memberCallExpr(on(hasType(namedDecl(stlShrinkableContainer()))),
callee(methodDecl(hasName("swap"))),
has(memberExpr(hasDescendant(CopyCtorCall))),
hasArgument(0, SwapParam.bind("ContainerToShrink")),
unless(isInTemplateInstantiation()))
.bind("CopyAndSwapTrick"),
this);
}
void AssertSideEffectCheck::registerMatchers(MatchFinder *Finder) {
auto DescendantWithSideEffect =
hasDescendant(expr(hasSideEffect(CheckFunctionCalls)));
auto ConditionWithSideEffect = hasCondition(DescendantWithSideEffect);
Finder->addMatcher(
stmt(
anyOf(conditionalOperator(ConditionWithSideEffect),
ifStmt(ConditionWithSideEffect),
unaryOperator(hasOperatorName("!"),
hasUnaryOperand(unaryOperator(
hasOperatorName("!"),
hasUnaryOperand(DescendantWithSideEffect))))))
.bind("condStmt"),
this);
}
void ContainerSizeEmptyCheck::registerMatchers(MatchFinder *Finder) {
const auto WrongUse = anyOf(
hasParent(
binaryOperator(
anyOf(has(integerLiteral(equals(0))),
allOf(anyOf(hasOperatorName("<"), hasOperatorName(">="),
hasOperatorName(">"), hasOperatorName("<=")),
hasEitherOperand(integerLiteral(equals(1))))))
.bind("SizeBinaryOp")),
hasParent(implicitCastExpr(
hasImplicitDestinationType(isBoolType()),
anyOf(
hasParent(unaryOperator(hasOperatorName("!")).bind("NegOnSize")),
anything()))),
hasParent(explicitCastExpr(hasDestinationType(isBoolType()))));
Finder->addMatcher(
memberCallExpr(
on(expr(anyOf(hasType(namedDecl(stlContainer())),
hasType(pointsTo(namedDecl(stlContainer()))),
hasType(references(namedDecl(stlContainer())))))
.bind("STLObject")),
callee(methodDecl(hasName("size"))), WrongUse).bind("SizeCallExpr"),
this);
}
void ProBoundsPointerArithmeticCheck::registerMatchers(MatchFinder *Finder) {
if (!getLangOpts().CPlusPlus)
return;
// Flag all operators +, -, +=, -=, ++, -- that result in a pointer
Finder->addMatcher(
binaryOperator(
anyOf(hasOperatorName("+"), hasOperatorName("-"),
hasOperatorName("+="), hasOperatorName("-=")),
hasType(pointerType()),
unless(hasLHS(ignoringImpCasts(declRefExpr(to(isImplicit()))))))
.bind("expr"),
this);
Finder->addMatcher(
unaryOperator(anyOf(hasOperatorName("++"), hasOperatorName("--")),
hasType(pointerType()))
.bind("expr"),
this);
// Array subscript on a pointer (not an array) is also pointer arithmetic
Finder->addMatcher(
arraySubscriptExpr(
hasBase(ignoringImpCasts(
anyOf(hasType(pointerType()),
hasType(decayedType(hasDecayedType(pointerType())))))))
.bind("expr"),
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 SignedBitwiseCheck::registerMatchers(MatchFinder *Finder) {
const auto SignedIntegerOperand =
expr(ignoringImpCasts(hasType(isSignedInteger()))).bind("signed-operand");
// The standard [bitmask.types] allows some integral types to be implemented
// as signed types. Exclude these types from diagnosing for bitwise or(|) and
// bitwise and(&). Shifting and complementing such values is still not
// allowed.
const auto BitmaskType = namedDecl(anyOf(
hasName("::std::locale::category"), hasName("::std::ctype_base::mask"),
hasName("::std::ios_base::fmtflags"), hasName("::std::ios_base::iostate"),
hasName("::std::ios_base::openmode")));
const auto IsStdBitmask = ignoringImpCasts(declRefExpr(hasType(BitmaskType)));
// Match binary bitwise operations on signed integer arguments.
Finder->addMatcher(
binaryOperator(
allOf(anyOf(hasOperatorName("^"), hasOperatorName("|"),
hasOperatorName("&"), hasOperatorName("^="),
hasOperatorName("|="), hasOperatorName("&=")),
unless(allOf(hasLHS(IsStdBitmask), hasRHS(IsStdBitmask))),
hasEitherOperand(SignedIntegerOperand),
hasLHS(hasType(isInteger())), hasRHS(hasType(isInteger()))))
.bind("binary-no-sign-interference"),
this);
// Shifting and complement is not allowed for any signed integer type because
// the sign bit may corrupt the result.
Finder->addMatcher(
binaryOperator(
allOf(anyOf(hasOperatorName("<<"), hasOperatorName(">>"),
hasOperatorName("<<="), hasOperatorName(">>=")),
hasEitherOperand(SignedIntegerOperand),
hasLHS(hasType(isInteger())), hasRHS(hasType(isInteger()))))
.bind("binary-sign-interference"),
this);
// Match unary operations on signed integer types.
Finder->addMatcher(unaryOperator(allOf(hasOperatorName("~"),
hasUnaryOperand(SignedIntegerOperand)))
.bind("unary-signed"),
this);
}
void NonConstParameterCheck::registerMatchers(MatchFinder *Finder) {
// Add parameters to Parameters.
Finder->addMatcher(parmVarDecl(unless(isInstantiated())).bind("Parm"), this);
// C++ constructor.
Finder->addMatcher(cxxConstructorDecl().bind("Ctor"), this);
// Track unused parameters, there is Wunused-parameter about unused
// parameters.
Finder->addMatcher(declRefExpr().bind("Ref"), this);
// Analyse parameter usage in function.
Finder->addMatcher(stmt(anyOf(unaryOperator(anyOf(hasOperatorName("++"),
hasOperatorName("--"))),
binaryOperator(), callExpr(), returnStmt(),
cxxConstructExpr()))
.bind("Mark"),
this);
Finder->addMatcher(varDecl(hasInitializer(anything())).bind("Mark"), this);
}
void ContainerSizeEmptyCheck::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;
const auto ValidContainer = cxxRecordDecl(isSameOrDerivedFrom(
namedDecl(
has(cxxMethodDecl(
isConst(), parameterCountIs(0), isPublic(), hasName("size"),
returns(qualType(isInteger(), unless(booleanType()))))
.bind("size")),
has(cxxMethodDecl(isConst(), parameterCountIs(0), isPublic(),
hasName("empty"), returns(booleanType()))
.bind("empty")))
.bind("container")));
const auto WrongUse = anyOf(
hasParent(binaryOperator(
matchers::isComparisonOperator(),
hasEitherOperand(ignoringImpCasts(anyOf(
integerLiteral(equals(1)), integerLiteral(equals(0))))))
.bind("SizeBinaryOp")),
hasParent(implicitCastExpr(
hasImplicitDestinationType(booleanType()),
anyOf(
hasParent(unaryOperator(hasOperatorName("!")).bind("NegOnSize")),
anything()))),
hasParent(explicitCastExpr(hasDestinationType(booleanType()))));
Finder->addMatcher(
cxxMemberCallExpr(on(expr(anyOf(hasType(ValidContainer),
hasType(pointsTo(ValidContainer)),
hasType(references(ValidContainer))))
.bind("STLObject")),
callee(cxxMethodDecl(hasName("size"))), WrongUse)
.bind("SizeCallExpr"),
this);
}
void MisplacedWideningCastCheck::registerMatchers(MatchFinder *Finder) {
const auto Calc =
expr(anyOf(binaryOperator(
anyOf(hasOperatorName("+"), hasOperatorName("-"),
hasOperatorName("*"), hasOperatorName("<<"))),
unaryOperator(hasOperatorName("~"))),
hasType(isInteger()))
.bind("Calc");
const auto ExplicitCast = explicitCastExpr(hasDestinationType(isInteger()),
has(ignoringParenImpCasts(Calc)));
const auto ImplicitCast =
implicitCastExpr(hasImplicitDestinationType(isInteger()),
has(ignoringParenImpCasts(Calc)));
const auto Cast = expr(anyOf(ExplicitCast, ImplicitCast)).bind("Cast");
Finder->addMatcher(varDecl(hasInitializer(Cast)), this);
Finder->addMatcher(returnStmt(hasReturnValue(Cast)), this);
Finder->addMatcher(callExpr(hasAnyArgument(Cast)), this);
Finder->addMatcher(binaryOperator(hasOperatorName("="), hasRHS(Cast)), this);
Finder->addMatcher(
binaryOperator(matchers::isComparisonOperator(), hasEitherOperand(Cast)),
this);
}
void NonCopyableObjectsCheck::registerMatchers(MatchFinder *Finder) {
// There are two ways to get into trouble with objects like FILE *:
// dereferencing the pointer type to be a non-pointer type, and declaring
// the type as a non-pointer type in the first place. While the declaration
// itself could technically be well-formed in the case where the type is not
// an opaque type, it's highly suspicious behavior.
//
// POSIX types are a bit different in that it's reasonable to declare a
// non-pointer variable or data member of the type, but it is not reasonable
// to dereference a pointer to the type, or declare a parameter of non-pointer
// type.
auto BadFILEType = hasType(namedDecl(isFILEType()).bind("type_decl"));
auto BadPOSIXType = hasType(namedDecl(isPOSIXType()).bind("type_decl"));
auto BadEitherType = anyOf(BadFILEType, BadPOSIXType);
Finder->addMatcher(
namedDecl(anyOf(varDecl(BadFILEType), fieldDecl(BadFILEType)))
.bind("decl"),
this);
Finder->addMatcher(parmVarDecl(BadPOSIXType).bind("decl"), this);
Finder->addMatcher(
expr(unaryOperator(hasOperatorName("*"), BadEitherType)).bind("expr"),
this);
}
void SuspiciousStringCompareCheck::registerMatchers(MatchFinder *Finder) {
// Match relational operators.
const auto ComparisonUnaryOperator = unaryOperator(hasOperatorName("!"));
const auto ComparisonBinaryOperator =
binaryOperator(matchers::isComparisonOperator());
const auto ComparisonOperator =
expr(anyOf(ComparisonUnaryOperator, ComparisonBinaryOperator));
// Add the list of known string compare-like functions and add user-defined
// functions.
std::vector<std::string> FunctionNames = utils::options::parseStringList(
(llvm::Twine(KnownStringCompareFunctions) + StringCompareLikeFunctions)
.str());
// Match a call to a string compare functions.
const auto FunctionCompareDecl =
functionDecl(hasAnyName(std::vector<StringRef>(FunctionNames.begin(),
FunctionNames.end())))
.bind("decl");
const auto DirectStringCompareCallExpr =
callExpr(hasDeclaration(FunctionCompareDecl)).bind("call");
const auto MacroStringCompareCallExpr = conditionalOperator(anyOf(
hasTrueExpression(ignoringParenImpCasts(DirectStringCompareCallExpr)),
hasFalseExpression(ignoringParenImpCasts(DirectStringCompareCallExpr))));
// The implicit cast is not present in C.
const auto StringCompareCallExpr = ignoringParenImpCasts(
anyOf(DirectStringCompareCallExpr, MacroStringCompareCallExpr));
if (WarnOnImplicitComparison) {
// Detect suspicious calls to string compare:
// 'if (strcmp())' -> 'if (strcmp() != 0)'
Finder->addMatcher(
stmt(anyOf(ifStmt(hasCondition(StringCompareCallExpr)),
whileStmt(hasCondition(StringCompareCallExpr)),
doStmt(hasCondition(StringCompareCallExpr)),
forStmt(hasCondition(StringCompareCallExpr)),
binaryOperator(
anyOf(hasOperatorName("&&"), hasOperatorName("||")),
hasEitherOperand(StringCompareCallExpr))))
.bind("missing-comparison"),
this);
}
if (WarnOnLogicalNotComparison) {
// Detect suspicious calls to string compared with '!' operator:
// 'if (!strcmp())' -> 'if (strcmp() == 0)'
Finder->addMatcher(unaryOperator(hasOperatorName("!"),
hasUnaryOperand(ignoringParenImpCasts(
StringCompareCallExpr)))
.bind("logical-not-comparison"),
this);
}
// Detect suspicious cast to an inconsistant type (i.e. not integer type).
Finder->addMatcher(
implicitCastExpr(unless(hasType(isInteger())),
hasSourceExpression(StringCompareCallExpr))
.bind("invalid-conversion"),
this);
// Detect suspicious operator with string compare function as operand.
Finder->addMatcher(
binaryOperator(
unless(anyOf(matchers::isComparisonOperator(), hasOperatorName("&&"),
hasOperatorName("||"), hasOperatorName("="))),
hasEitherOperand(StringCompareCallExpr))
.bind("suspicious-operator"),
this);
// Detect comparison to invalid constant: 'strcmp() == -1'.
const auto InvalidLiteral = ignoringParenImpCasts(
anyOf(integerLiteral(unless(equals(0))),
unaryOperator(
hasOperatorName("-"),
has(ignoringParenImpCasts(integerLiteral(unless(equals(0)))))),
characterLiteral(), cxxBoolLiteral()));
Finder->addMatcher(binaryOperator(matchers::isComparisonOperator(),
hasEitherOperand(StringCompareCallExpr),
hasEitherOperand(InvalidLiteral))
.bind("invalid-comparison"),
this);
}