// RUN: %check_clang_tidy -std=c++17-or-later %s bugprone-easily-swappable-parameters %t \ // RUN: -config='{CheckOptions: { \ // RUN: bugprone-easily-swappable-parameters.MinimumLength: 2, \ // RUN: bugprone-easily-swappable-parameters.IgnoredParameterNames: "", \ // RUN: bugprone-easily-swappable-parameters.IgnoredParameterTypeSuffixes: "", \ // RUN: bugprone-easily-swappable-parameters.QualifiersMix: 0, \ // RUN: bugprone-easily-swappable-parameters.ModelImplicitConversions: 1, \ // RUN: bugprone-easily-swappable-parameters.SuppressParametersUsedTogether: 0, \ // RUN: bugprone-easily-swappable-parameters.NamePrefixSuffixSilenceDissimilarityTreshold: 0 \ // RUN: }}' -- void implicitDoesntBreakOtherStuff(int A, int B) {} // CHECK-MESSAGES: :[[@LINE-1]]:36: warning: 2 adjacent parameters of 'implicitDoesntBreakOtherStuff' of similar type ('int') are easily swapped by mistake [bugprone-easily-swappable-parameters] // CHECK-MESSAGES: :[[@LINE-2]]:40: note: the first parameter in the range is 'A' // CHECK-MESSAGES: :[[@LINE-3]]:47: note: the last parameter in the range is 'B' void arrayAndPtr1(int *IP, int IA[]) { arrayAndPtr1(IA, IP); } // CHECK-MESSAGES: :[[@LINE-1]]:19: warning: 2 adjacent parameters of 'arrayAndPtr1' of similar type ('int *') // CHECK-MESSAGES: :[[@LINE-2]]:24: note: the first parameter in the range is 'IP' // CHECK-MESSAGES: :[[@LINE-3]]:32: note: the last parameter in the range is 'IA' void arrayAndPtr2(int *IP, int IA[8]) { arrayAndPtr2(IA, IP); } // CHECK-MESSAGES: :[[@LINE-1]]:19: warning: 2 adjacent parameters of 'arrayAndPtr2' of similar type ('int *') // CHECK-MESSAGES: :[[@LINE-2]]:24: note: the first parameter in the range is 'IP' // CHECK-MESSAGES: :[[@LINE-3]]:32: note: the last parameter in the range is 'IA' void arrayAndElement(int I, int IA[]) {} // NO-WARN. typedef int Point2D[2]; typedef int Point3D[3]; void arrays1(Point2D P2D, Point3D P3D) {} // In reality this is (int*, int*). // CHECK-MESSAGES: :[[@LINE-1]]:14: warning: 2 adjacent parameters of 'arrays1' of similar type ('int *') are // CHECK-MESSAGES: :[[@LINE-2]]:22: note: the first parameter in the range is 'P2D' // CHECK-MESSAGES: :[[@LINE-3]]:35: note: the last parameter in the range is 'P3D' void crefToArrayTypedef1(int I, const Point2D &P) {} // NO-WARN. void crefToArrayTypedef2(int *IA, const Point2D &P) {} // NO-WARN. void crefToArrayTypedef3(int P1[2], const Point2D &P) {} // NO-WARN. void crefToArrayTypedefBoth1(const Point2D &VecDescartes, const Point3D &VecThreeD) {} // NO-WARN: Distinct types. template void templatedArrayRef(int (&Array1)[N], int (&Array2)[M]) {} // NO-WARN: Distinct template types in the primary template. void templatedArrayRefTest() { int Foo[12], Bar[12]; templatedArrayRef(Foo, Bar); int Baz[12], Quux[42]; templatedArrayRef(Baz, Quux); // NO-WARN: Implicit instantiations are not checked. } template <> void templatedArrayRef(int (&Array1)[8], int (&Array2)[8]) { templatedArrayRef(Array2, Array1); } // CHECK-MESSAGES: :[[@LINE-1]]:24: warning: 2 adjacent parameters of 'templatedArrayRef<8, 8>' of similar type ('int (&)[8]') are // CHECK-MESSAGES: :[[@LINE-2]]:30: note: the first parameter in the range is 'Array1' // CHECK-MESSAGES: :[[@LINE-3]]:48: note: the last parameter in the range is 'Array2' template <> void templatedArrayRef(int (&Array1)[16], int (&Array2)[24]) {} // NO-WARN: Not the same type. void numericConversion1(int I, double D) { numericConversion1(D, I); } // CHECK-MESSAGES: :[[@LINE-1]]:25: warning: 2 adjacent parameters of 'numericConversion1' of convertible types are easily swapped by mistake [bugprone-easily-swappable-parameters] // CHECK-MESSAGES: :[[@LINE-2]]:29: note: the first parameter in the range is 'I' // CHECK-MESSAGES: :[[@LINE-3]]:39: note: the last parameter in the range is 'D' // CHECK-MESSAGES: :[[@LINE-4]]:32: note: 'int' and 'double' may be implicitly converted{{$}} void numericConversion2(int I, short S) { numericConversion2(S, I); } // CHECK-MESSAGES: :[[@LINE-1]]:25: warning: 2 adjacent parameters of 'numericConversion2' of convertible types // CHECK-MESSAGES: :[[@LINE-2]]:29: note: the first parameter in the range is 'I' // CHECK-MESSAGES: :[[@LINE-3]]:38: note: the last parameter in the range is 'S' // CHECK-MESSAGES: :[[@LINE-4]]:32: note: 'int' and 'short' may be implicitly converted{{$}} void numericConversion3(float F, unsigned long long ULL) { numericConversion3(ULL, F); } // CHECK-MESSAGES: :[[@LINE-1]]:25: warning: 2 adjacent parameters of 'numericConversion3' of convertible types // CHECK-MESSAGES: :[[@LINE-2]]:31: note: the first parameter in the range is 'F' // CHECK-MESSAGES: :[[@LINE-3]]:53: note: the last parameter in the range is 'ULL' // CHECK-MESSAGES: :[[@LINE-4]]:34: note: 'float' and 'unsigned long long' may be implicitly converted{{$}} enum Unscoped { U_A, U_B }; enum UnscopedFixed : char { UF_A, UF_B }; enum struct Scoped { A, B }; void numericConversion4(int I, Unscoped U) {} // NO-WARN. void numericConversion5(int I, UnscopedFixed UF) {} // NO-WARN. void numericConversion6(int I, Scoped S) {} // NO-WARN. void numericConversion7(double D, Unscoped U) {} // NO-WARN. void numericConversion8(double D, UnscopedFixed UF) {} // NO-WARN. void numericConversion9(double D, Scoped S) {} // NO-WARN. void numericConversionMultiUnique(int I, double D1, double D2) {} // CHECK-MESSAGES: :[[@LINE-1]]:35: warning: 3 adjacent parameters of 'numericConversionMultiUnique' of convertible types // CHECK-MESSAGES: :[[@LINE-2]]:39: note: the first parameter in the range is 'I' // CHECK-MESSAGES: :[[@LINE-3]]:60: note: the last parameter in the range is 'D2' // CHECK-MESSAGES: :[[@LINE-4]]:42: note: 'int' and 'double' may be implicitly converted{{$}} // (Note: int<->double conversion for I<->D2 not diagnosed again.) typedef int MyInt; using MyDouble = double; void numericConversion10(MyInt MI, MyDouble MD) { numericConversion10(MD, MI); } // CHECK-MESSAGES: :[[@LINE-1]]:26: warning: 2 adjacent parameters of 'numericConversion10' of convertible types // CHECK-MESSAGES: :[[@LINE-2]]:32: note: the first parameter in the range is 'MI' // CHECK-MESSAGES: :[[@LINE-3]]:45: note: the last parameter in the range is 'MD' // CHECK-MESSAGES: :[[@LINE-4]]:36: note: 'MyInt' and 'MyDouble' may be implicitly converted: 'MyInt' (as 'int') -> 'MyDouble' (as 'double'), 'MyDouble' (as 'double') -> 'MyInt' (as 'int') void numericAndQualifierConversion(int I, const double CD) { numericAndQualifierConversion(CD, I); } // NO-WARN: Qualifier mixing is handled by a different check option. struct FromInt { FromInt(int); }; void oneWayConversion1(int I, FromInt FI) {} // NO-WARN: One-way. struct AmbiguousConvCtor { AmbiguousConvCtor(int); AmbiguousConvCtor(double); }; void ambiguous1(long L, AmbiguousConvCtor ACC) {} // NO-WARN: Ambiguous, one-way. struct ToInt { operator int() const; }; void oneWayConversion2(ToInt TI, int I) {} // NO-WARN: One-way. struct AmbiguousConvOp { operator int() const; operator double() const; }; void ambiguous2(AmbiguousConvOp ACO, long L) {} // NO-WARN: Ambiguous, one-way. struct AmbiguousEverything1; struct AmbiguousEverything2; struct AmbiguousEverything1 { AmbiguousEverything1(); AmbiguousEverything1(AmbiguousEverything2); operator AmbiguousEverything2() const; }; struct AmbiguousEverything2 { AmbiguousEverything2(); AmbiguousEverything2(AmbiguousEverything1); operator AmbiguousEverything1() const; }; void ambiguous3(AmbiguousEverything1 AE1, AmbiguousEverything2 AE2) {} // NO-WARN: Ambiguous. struct Integer { Integer(int); operator int() const; }; void userDefinedConversion1(int I1, Integer I2) { userDefinedConversion1(I2, I1); } // CHECK-MESSAGES: :[[@LINE-1]]:29: warning: 2 adjacent parameters of 'userDefinedConversion1' of convertible types // CHECK-MESSAGES: :[[@LINE-2]]:33: note: the first parameter in the range is 'I1' // CHECK-MESSAGES: :[[@LINE-3]]:45: note: the last parameter in the range is 'I2' // CHECK-MESSAGES: :[[@LINE-4]]:37: note: 'int' and 'Integer' may be implicitly converted{{$}} // CHECK-MESSAGES: :[[@LINE-9]]:3: note: the implicit conversion involves the converting constructor declared here // CHECK-MESSAGES: :[[@LINE-9]]:3: note: the implicit conversion involves the conversion operator declared here struct Ambiguous { Ambiguous(int); Ambiguous(double); operator long() const; operator float() const; }; void ambiguous3(char C, Ambiguous A) {} // NO-WARN: Ambiguous. struct CDouble { CDouble(const double &); operator const double &() const; }; void userDefinedConversion2(double D, CDouble CD) { userDefinedConversion2(CD, D); } // CHECK-MESSAGES: :[[@LINE-1]]:29: warning: 2 adjacent parameters of 'userDefinedConversion2' of convertible types // CHECK-MESSAGES: :[[@LINE-2]]:36: note: the first parameter in the range is 'D' // CHECK-MESSAGES: :[[@LINE-3]]:47: note: the last parameter in the range is 'CD' // CHECK-MESSAGES: :[[@LINE-4]]:39: note: 'double' and 'CDouble' may be implicitly converted: 'double' -> 'const double &' -> 'CDouble', 'CDouble' -> 'const double &' -> 'double' // CHECK-MESSAGES: :[[@LINE-9]]:3: note: the implicit conversion involves the converting constructor declared here // CHECK-MESSAGES: :[[@LINE-9]]:3: note: the implicit conversion involves the conversion operator declared here void userDefinedConversion3(int I, CDouble CD) { userDefinedConversion3(CD, I); } // CHECK-MESSAGES: :[[@LINE-1]]:29: warning: 2 adjacent parameters of 'userDefinedConversion3' of convertible types // CHECK-MESSAGES: :[[@LINE-2]]:33: note: the first parameter in the range is 'I' // CHECK-MESSAGES: :[[@LINE-3]]:44: note: the last parameter in the range is 'CD' // CHECK-MESSAGES: :[[@LINE-4]]:36: note: 'int' and 'CDouble' may be implicitly converted: 'int' -> 'double' -> 'const double &' -> 'CDouble', 'CDouble' -> 'const double &' -> 'int' // CHECK-MESSAGES: :[[@LINE-17]]:3: note: the implicit conversion involves the converting constructor declared here // CHECK-MESSAGES: :[[@LINE-17]]:3: note: the implicit conversion involves the conversion operator declared here struct TDInt { TDInt(const MyInt &); operator MyInt() const; }; void userDefinedConversion4(int I, TDInt TDI) { userDefinedConversion4(TDI, I); } // CHECK-MESSAGES: :[[@LINE-1]]:29: warning: 2 adjacent parameters of 'userDefinedConversion4' of convertible types // CHECK-MESSAGES: :[[@LINE-2]]:33: note: the first parameter in the range is 'I' // CHECK-MESSAGES: :[[@LINE-3]]:42: note: the last parameter in the range is 'TDI' // CHECK-MESSAGES: :[[@LINE-4]]:36: note: 'int' and 'TDInt' may be implicitly converted: 'int' -> 'const MyInt &' -> 'TDInt', 'TDInt' -> 'MyInt' -> 'int' // CHECK-MESSAGES: :[[@LINE-9]]:3: note: the implicit conversion involves the converting constructor declared here // CHECK-MESSAGES: :[[@LINE-9]]:3: note: the implicit conversion involves the conversion operator declared here struct TDIntDouble { TDIntDouble(const MyInt &); TDIntDouble(const MyDouble &); operator MyInt() const; operator MyDouble() const; }; void userDefinedConversion5(int I, TDIntDouble TDID) { userDefinedConversion5(TDID, I); } // CHECK-MESSAGES: :[[@LINE-1]]:29: warning: 2 adjacent parameters of 'userDefinedConversion5' of convertible types // CHECK-MESSAGES: :[[@LINE-2]]:33: note: the first parameter in the range is 'I' // CHECK-MESSAGES: :[[@LINE-3]]:48: note: the last parameter in the range is 'TDID' // CHECK-MESSAGES: :[[@LINE-4]]:36: note: 'int' and 'TDIntDouble' may be implicitly converted: 'int' -> 'const MyInt &' -> 'TDIntDouble', 'TDIntDouble' -> 'MyInt' -> 'int' // CHECK-MESSAGES: :[[@LINE-11]]:3: note: the implicit conversion involves the converting constructor declared here // CHECK-MESSAGES: :[[@LINE-10]]:3: note: the implicit conversion involves the conversion operator declared here void userDefinedConversion6(double D, TDIntDouble TDID) { userDefinedConversion6(TDID, D); } // CHECK-MESSAGES: :[[@LINE-1]]:29: warning: 2 adjacent parameters of 'userDefinedConversion6' of convertible types // CHECK-MESSAGES: :[[@LINE-2]]:36: note: the first parameter in the range is 'D' // CHECK-MESSAGES: :[[@LINE-3]]:51: note: the last parameter in the range is 'TDID' // CHECK-MESSAGES: :[[@LINE-4]]:39: note: 'double' and 'TDIntDouble' may be implicitly converted: 'double' -> 'const MyDouble &' -> 'TDIntDouble', 'TDIntDouble' -> 'MyDouble' -> 'double' // CHECK-MESSAGES: :[[@LINE-18]]:3: note: the implicit conversion involves the converting constructor declared here // CHECK-MESSAGES: :[[@LINE-17]]:3: note: the implicit conversion involves the conversion operator declared here void userDefinedConversion7(char C, TDIntDouble TDID) {} // NO-WARN: Ambiguous. struct Forward1; struct Forward2; void incomplete(Forward1 *F1, Forward2 *F2) {} // NO-WARN: Do not compare incomplete types. void pointeeConverison(int *IP, double *DP) {} // NO-WARN. void pointerConversion1(void *VP, int *IP) {} // NO-WARN: One-way. struct PointerBox { PointerBox(void *); operator int *() const; }; void pointerConversion2(PointerBox PB, int *IP) { pointerConversion2(IP, PB); } // CHECK-MESSAGES: :[[@LINE-1]]:25: warning: 2 adjacent parameters of 'pointerConversion2' of convertible types // CHECK-MESSAGES: :[[@LINE-2]]:36: note: the first parameter in the range is 'PB' // CHECK-MESSAGES: :[[@LINE-3]]:45: note: the last parameter in the range is 'IP' // CHECK-MESSAGES: :[[@LINE-4]]:40: note: 'PointerBox' and 'int *' may be implicitly converted: 'PointerBox' -> 'int *', 'int *' -> 'void *' -> 'PointerBox' // CHECK-MESSAGES: :[[@LINE-8]]:3: note: the implicit conversion involves the conversion operator declared here // CHECK-MESSAGES: :[[@LINE-10]]:3: note: the implicit conversion involves the converting constructor declared here void pointerConversion3(PointerBox PB, double *DP) {} // NO-WARN: Not convertible. struct Base {}; struct Derived : Base {}; void pointerConversion4(Base *BP, Derived *DP) {} // NO-WARN: One-way. struct BaseAndDerivedInverter { BaseAndDerivedInverter(Base); // Takes a Base operator Derived() const; // and becomes a Derived. }; void pointerConversion5(BaseAndDerivedInverter BADI, Derived D) { pointerConversion5(D, BADI); } // CHECK-MESSAGES: :[[@LINE-1]]:25: warning: 2 adjacent parameters of 'pointerConversion5' of convertible types // CHECK-MESSAGES: :[[@LINE-2]]:48: note: the first parameter in the range is 'BADI' // CHECK-MESSAGES: :[[@LINE-3]]:62: note: the last parameter in the range is 'D' // CHECK-MESSAGES: :[[@LINE-4]]:54: note: 'BaseAndDerivedInverter' and 'Derived' may be implicitly converted: 'BaseAndDerivedInverter' -> 'Derived', 'Derived' -> 'Base' -> 'BaseAndDerivedInverter' // CHECK-MESSAGES: :[[@LINE-8]]:3: note: the implicit conversion involves the conversion operator declared here // CHECK-MESSAGES: :[[@LINE-10]]:3: note: the implicit conversion involves the converting constructor declared here void pointerConversion6(void (*NTF)() noexcept, void (*TF)()) {} // NO-WARN: This call cannot be swapped, even if "getCanonicalType()" believes otherwise. using NonThrowingFunction = void (*)() noexcept; struct NoexceptMaker { NoexceptMaker(void (*ThrowingFunction)()); // Need to use a typedef here because // "conversion function cannot convert to a function type". // operator (void (*)() noexcept) () const; operator NonThrowingFunction() const; }; void pointerConversion7(void (*NTF)() noexcept, NoexceptMaker NM) { pointerConversion7(NM, NTF); } // CHECK-MESSAGES: :[[@LINE-1]]:25: warning: 2 adjacent parameters of 'pointerConversion7' of convertible types // CHECK-MESSAGES: :[[@LINE-2]]:32: note: the first parameter in the range is 'NTF' // CHECK-MESSAGES: :[[@LINE-3]]:63: note: the last parameter in the range is 'NM' // CHECK-MESSAGES: :[[@LINE-4]]:49: note: 'void (*)() noexcept' and 'NoexceptMaker' may be implicitly converted: 'void (*)() noexcept' -> 'void (*)()' -> 'NoexceptMaker', 'NoexceptMaker' -> 'NonThrowingFunction' -> 'void (*)() noexcept' // CHECK-MESSAGES: :[[@LINE-12]]:3: note: the implicit conversion involves the converting constructor declared here // CHECK-MESSAGES: :[[@LINE-9]]:3: note: the implicit conversion involves the conversion operator declared here struct ToType; struct MiddleStep1 { operator ToType() const; }; struct FromType { operator MiddleStep1() const; }; struct MiddleStep2 { operator FromType() const; }; struct ToType { operator MiddleStep2() const; }; void f(FromType F, ToType T) { // NO-WARN: The path takes two steps. MiddleStep2 MS2 = T; FromType F2 = MS2; MiddleStep1 MS1 = F; ToType T2 = MS1; f(F2, T2); } // Synthesised example from OpenCV. template struct TemplateConversion { template operator TemplateConversion() const; }; using IntConverter = TemplateConversion; using FloatConverter = TemplateConversion; void templateConversion(IntConverter IC, FloatConverter FC) { templateConversion(FC, IC); } // Note: even though this swap is possible, we do not model things when it comes to "template magic". // But at least the check should not crash!