Author: Congcong Cai Date: 2025-01-11T18:48:39+08:00 New Revision: 32bcd41adcc664f6d690efc9b7cd209ac9c65f68
URL: https://github.com/llvm/llvm-project/commit/32bcd41adcc664f6d690efc9b7cd209ac9c65f68 DIFF: https://github.com/llvm/llvm-project/commit/32bcd41adcc664f6d690efc9b7cd209ac9c65f68.diff LOG: [clang-tidy] use correct template type in ``std::min`` and ``std::max`` when operand is integer literal for readability-use-std-min-max (#122296) When comparing with integer literal, integer promote will happen to promote type which has less bit width than int to int or unsigned int. It will let auto-fix provide correct but out of expected fix. e.g. ```c++ short a; if ( a > 10 ) a = 10; ``` will be ```c++ short a; if ( (int)a > 10 ) a = (short)10; ``` which will be fixed as ```c++ short a; a = std::max<int>(a, 10); ``` but actually it can be ```c++ short a; a = std::max<short>(a, 10); ``` Fixed: #121676 Added: Modified: clang-tools-extra/clang-tidy/readability/UseStdMinMaxCheck.cpp clang-tools-extra/docs/ReleaseNotes.rst clang-tools-extra/test/clang-tidy/checkers/readability/use-std-min-max.cpp Removed: ################################################################################ diff --git a/clang-tools-extra/clang-tidy/readability/UseStdMinMaxCheck.cpp b/clang-tools-extra/clang-tidy/readability/UseStdMinMaxCheck.cpp index 179173502a8d01..6f6b8a853a91e0 100644 --- a/clang-tools-extra/clang-tidy/readability/UseStdMinMaxCheck.cpp +++ b/clang-tools-extra/clang-tidy/readability/UseStdMinMaxCheck.cpp @@ -79,6 +79,27 @@ static QualType getNonTemplateAlias(QualType QT) { return QT; } +static QualType getReplacementCastType(const Expr *CondLhs, const Expr *CondRhs, + QualType ComparedType) { + QualType LhsType = CondLhs->getType(); + QualType RhsType = CondRhs->getType(); + QualType LhsCanonicalType = + LhsType.getCanonicalType().getNonReferenceType().getUnqualifiedType(); + QualType RhsCanonicalType = + RhsType.getCanonicalType().getNonReferenceType().getUnqualifiedType(); + QualType GlobalImplicitCastType; + if (LhsCanonicalType != RhsCanonicalType) { + if (llvm::isa<IntegerLiteral>(CondRhs)) { + GlobalImplicitCastType = getNonTemplateAlias(LhsType); + } else if (llvm::isa<IntegerLiteral>(CondLhs)) { + GlobalImplicitCastType = getNonTemplateAlias(RhsType); + } else { + GlobalImplicitCastType = getNonTemplateAlias(ComparedType); + } + } + return GlobalImplicitCastType; +} + static std::string createReplacement(const Expr *CondLhs, const Expr *CondRhs, const Expr *AssignLhs, const SourceManager &Source, @@ -92,18 +113,8 @@ static std::string createReplacement(const Expr *CondLhs, const Expr *CondRhs, const llvm::StringRef AssignLhsStr = Lexer::getSourceText( Source.getExpansionRange(AssignLhs->getSourceRange()), Source, LO); - QualType GlobalImplicitCastType; - QualType LhsType = CondLhs->getType() - .getCanonicalType() - .getNonReferenceType() - .getUnqualifiedType(); - QualType RhsType = CondRhs->getType() - .getCanonicalType() - .getNonReferenceType() - .getUnqualifiedType(); - if (LhsType != RhsType) { - GlobalImplicitCastType = getNonTemplateAlias(BO->getLHS()->getType()); - } + QualType GlobalImplicitCastType = + getReplacementCastType(CondLhs, CondRhs, BO->getLHS()->getType()); return (AssignLhsStr + " = " + FunctionName + (!GlobalImplicitCastType.isNull() diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst index 9cdad8fb6b58f2..d75a276729c581 100644 --- a/clang-tools-extra/docs/ReleaseNotes.rst +++ b/clang-tools-extra/docs/ReleaseNotes.rst @@ -369,6 +369,10 @@ Changes in existing checks <clang-tidy/checks/readability/redundant-smartptr-get>` check to remove `->`, when redundant `get()` is removed. +- Improved :doc:`readability-use-std-min-max + <clang-tidy/checks/readability/use-std-min-max>` check to use correct template + type in ``std::min`` and ``std::max`` when operand is integer literal. + Removed checks ^^^^^^^^^^^^^^ diff --git a/clang-tools-extra/test/clang-tidy/checkers/readability/use-std-min-max.cpp b/clang-tools-extra/test/clang-tidy/checkers/readability/use-std-min-max.cpp index 9c0e2eabda348d..35ade8a7c6d37e 100644 --- a/clang-tools-extra/test/clang-tidy/checkers/readability/use-std-min-max.cpp +++ b/clang-tools-extra/test/clang-tidy/checkers/readability/use-std-min-max.cpp @@ -252,3 +252,24 @@ void testVectorSizeType() { if (value < v.size()) value = v.size(); } + +namespace gh121676 { + +void useLeft() { + using U16 = unsigned short; + U16 I = 0; + // CHECK-MESSAGES: :[[@LINE+2]]:3: warning: use `std::max` instead of `<` [readability-use-std-min-max] + // CHECK-FIXES: I = std::max<U16>(I, 16U); + if (I < 16U) + I = 16U; +} +void useRight() { + using U16 = unsigned short; + U16 I = 0; + // CHECK-MESSAGES: :[[@LINE+2]]:3: warning: use `std::min` instead of `<` [readability-use-std-min-max] + // CHECK-FIXES: I = std::min<U16>(16U, I); + if (16U < I) + I = 16U; +} + +} // namespace gh121676 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
