Author: flx Date: Wed Nov 9 19:28:22 2016 New Revision: 286424 URL: http://llvm.org/viewvc/llvm-project?rev=286424&view=rev Log: [clang-tidy] Do not issue fix for functions that are referenced outside of callExpr
Summary: Suppress fixes for functions that are referenced within the compilation unit outside of a call expression as the signature change could break the code referencing the function. We still issue a warning in this case so that users can decide to manually change the function signature. Reviewers: alexfh, sbenza, aaron.ballman Subscribers: cfe-commits Differential Revision: https://reviews.llvm.org/D26203 Modified: clang-tools-extra/trunk/clang-tidy/performance/UnnecessaryValueParamCheck.cpp clang-tools-extra/trunk/test/clang-tidy/performance-unnecessary-value-param.cpp Modified: clang-tools-extra/trunk/clang-tidy/performance/UnnecessaryValueParamCheck.cpp URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/clang-tidy/performance/UnnecessaryValueParamCheck.cpp?rev=286424&r1=286423&r2=286424&view=diff ============================================================================== --- clang-tools-extra/trunk/clang-tidy/performance/UnnecessaryValueParamCheck.cpp (original) +++ clang-tools-extra/trunk/clang-tidy/performance/UnnecessaryValueParamCheck.cpp Wed Nov 9 19:28:22 2016 @@ -39,6 +39,14 @@ bool isSubset(const S &SubsetCandidate, return true; } +bool isReferencedOutsideOfCallExpr(const FunctionDecl &Function, + ASTContext &Context) { + auto Matches = match(declRefExpr(to(functionDecl(equalsNode(&Function))), + unless(hasAncestor(callExpr()))), + Context); + return !Matches.empty(); +} + } // namespace UnnecessaryValueParamCheck::UnnecessaryValueParamCheck( @@ -118,10 +126,14 @@ void UnnecessaryValueParamCheck::check(c "invocation but only used as a const reference; " "consider making it a const reference") << paramNameOrIndex(Param->getName(), Index); - // Do not propose fixes in macros since we cannot place them correctly, or if - // function is virtual as it might break overrides. + // Do not propose fixes when: + // 1. the ParmVarDecl is in a macro, since we cannot place them correctly + // 2. the function is virtual as it might break overrides + // 3. the function is referenced outside of a call expression within the + // compilation unit as the signature change could introduce build errors. const auto *Method = llvm::dyn_cast<CXXMethodDecl>(Function); - if (Param->getLocStart().isMacroID() || (Method && Method->isVirtual())) + if (Param->getLocStart().isMacroID() || (Method && Method->isVirtual()) || + isReferencedOutsideOfCallExpr(*Function, *Result.Context)) return; for (const auto *FunctionDecl = Function; FunctionDecl != nullptr; FunctionDecl = FunctionDecl->getPreviousDecl()) { Modified: clang-tools-extra/trunk/test/clang-tidy/performance-unnecessary-value-param.cpp URL: http://llvm.org/viewvc/llvm-project/clang-tools-extra/trunk/test/clang-tidy/performance-unnecessary-value-param.cpp?rev=286424&r1=286423&r2=286424&view=diff ============================================================================== --- clang-tools-extra/trunk/test/clang-tidy/performance-unnecessary-value-param.cpp (original) +++ clang-tools-extra/trunk/test/clang-tidy/performance-unnecessary-value-param.cpp Wed Nov 9 19:28:22 2016 @@ -253,3 +253,21 @@ void PositiveNonConstDeclaration(const E // CHECK-MESSAGES: [[@LINE-1]]:60: warning: the const qualified parameter 'A' // CHECK-FIXES: void PositiveNonConstDeclaration(const ExpensiveToCopyType& A) { } + +void PositiveOnlyMessageAsReferencedInCompilationUnit(ExpensiveToCopyType A) { + // CHECK-MESSAGES: [[@LINE-1]]:75: warning: the parameter 'A' is copied + // CHECK-FIXES: void PositiveOnlyMessageAsReferencedInCompilationUnit(ExpensiveToCopyType A) { +} + +void ReferenceFunctionOutsideOfCallExpr() { + void (*ptr)(ExpensiveToCopyType) = &PositiveOnlyMessageAsReferencedInCompilationUnit; +} + +void PositiveMessageAndFixAsFunctionIsCalled(ExpensiveToCopyType A) { + // CHECK-MESSAGES: [[@LINE-1]]:66: warning: the parameter 'A' is copied + // CHECK-FIXES: void PositiveMessageAndFixAsFunctionIsCalled(const ExpensiveToCopyType& A) { +} + +void ReferenceFunctionByCallingIt() { + PositiveMessageAndFixAsFunctionIsCalled(ExpensiveToCopyType()); +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
