// RUN: %check_clang_tidy -std=c++14-or-later %s performance-unnecessary-value-param %t struct ExpensiveToCopyType { virtual ~ExpensiveToCopyType(); }; template void templateWithNonTemplatizedParameter(const ExpensiveToCopyType S, T V) { // CHECK-MESSAGES: [[@LINE-1]]:90: warning: the const qualified parameter 'S' // CHECK-MESSAGES: [[@LINE-2]]:95: warning: the parameter 'V' // CHECK-FIXES: template void templateWithNonTemplatizedParameter(const ExpensiveToCopyType& S, const T& V) { } void instantiatedWithExpensiveValue() { templateWithNonTemplatizedParameter( ExpensiveToCopyType(), ExpensiveToCopyType()); templateWithNonTemplatizedParameter(ExpensiveToCopyType(), 5); } template void templateWithNonTemplatizedParameterCheapTemplate(const ExpensiveToCopyType S, T V) { // CHECK-MESSAGES: [[@LINE-1]]:103: warning: the const qualified parameter 'S' // CHECK-FIXES: template void templateWithNonTemplatizedParameterCheapTemplate(const ExpensiveToCopyType& S, T V) { } void instantiatedWithCheapValue() { templateWithNonTemplatizedParameterCheapTemplate(ExpensiveToCopyType(), 5); } template void nonInstantiatedTemplateWithConstValue(const T S) {} template void nonInstantiatedTemplateWithNonConstValue(T S) {} template void instantiatedTemplateSpecialization(T NoSpecS) {} template <> void instantiatedTemplateSpecialization(int SpecSInt) {} // Updating template specialization would also require to update the main // template and other specializations. Such specializations may be // spreaded across different translation units. // For that reason we only issue a warning, but do not propose fixes. template <> void instantiatedTemplateSpecialization( ExpensiveToCopyType SpecSExpensiveToCopy) { // CHECK-MESSAGES: [[@LINE-1]]:25: warning: the parameter 'SpecSExpensiveToCopy' // CHECK-FIXES-NOT: const T& NoSpecS // CHECK-FIXES-NOT: const int& SpecSInt // CHECK-FIXES-NOT: const ExpensiveToCopyType& SpecSExpensiveToCopy } void instantiatedTemplateSpecialization() { instantiatedTemplateSpecialization(ExpensiveToCopyType()); } template void instantiatedTemplateWithConstValue(const T S) { // CHECK-MESSAGES: [[@LINE-1]]:71: warning: the const qualified parameter 'S' // CHECK-FIXES: template void instantiatedTemplateWithConstValue(const T& S) { } void instantiatedConstValue() { instantiatedTemplateWithConstValue(ExpensiveToCopyType()); } template void instantiatedTemplateWithNonConstValue(T S) { // CHECK-MESSAGES: [[@LINE-1]]:68: warning: the parameter 'S' // CHECK-FIXES: template void instantiatedTemplateWithNonConstValue(const T& S) { } void instantiatedNonConstValue() { instantiatedTemplateWithNonConstValue(ExpensiveToCopyType()); } void lambdaConstValue() { auto fn = [](const ExpensiveToCopyType S) { // CHECK-MESSAGES: [[@LINE-1]]:42: warning: the const qualified parameter 'S' // CHECK-FIXES: auto fn = [](const ExpensiveToCopyType& S) { }; fn(ExpensiveToCopyType()); } void lambdaNonConstValue() { auto fn = [](ExpensiveToCopyType S) { // CHECK-MESSAGES: [[@LINE-1]]:36: warning: the parameter 'S' // CHECK-FIXES: auto fn = [](const ExpensiveToCopyType& S) { }; fn(ExpensiveToCopyType()); } void lambdaConstAutoValue() { auto fn = [](const auto S) { // CHECK-MESSAGES: [[@LINE-1]]:27: warning: the const qualified parameter 'S' // CHECK-FIXES: auto fn = [](const auto& S) { }; fn(ExpensiveToCopyType()); } void lambdaNonConstAutoValue() { auto fn = [](auto S) { // CHECK-MESSAGES: [[@LINE-1]]:21: warning: the parameter 'S' // CHECK-FIXES: auto fn = [](const auto& S) { }; fn(ExpensiveToCopyType()); } template void ParameterPack(Args... args) { // CHECK-MESSAGES: [[@LINE-1]]:28: warning: the parameter 'args' of type 'ExpensiveToCopyType' // CHECK-FIXES: void ParameterPack(const Args&... args) { } template void ParameterPackConst(Args const... args) { // CHECK-MESSAGES: [[@LINE-1]]:39: warning: the const qualified parameter 'args' of type 'const ExpensiveToCopyType' // CHECK-FIXES: void ParameterPackConst(Args const&... args) { } template void ParameterPackWithParams(const ExpensiveToCopyType E1, ExpensiveToCopyType E2, Args... args) { // CHECK-MESSAGES: [[@LINE-1]]:56: warning: the const qualified parameter 'E1' // CHECK-MESSAGES: [[@LINE-2]]:80: warning: the parameter 'E2' // CHECK-MESSAGES: [[@LINE-3]]:92: warning: the parameter 'args' // CHECK-FIXES: void ParameterPackWithParams(const ExpensiveToCopyType& E1, const ExpensiveToCopyType& E2, const Args&... args) { } template void PackWithNonExpensive(int x, Args... args) {} void instantiatedParameterPack() { ExpensiveToCopyType E; ParameterPack(E); ParameterPackConst(E); ParameterPackWithParams(E, E, E); PackWithNonExpensive(5, 5); }