Author: Congcong Cai Date: 2024-12-07T08:31:35+08:00 New Revision: a07e8cdae7727583e20c9dec632a376365a6e209
URL: https://github.com/llvm/llvm-project/commit/a07e8cdae7727583e20c9dec632a376365a6e209 DIFF: https://github.com/llvm/llvm-project/commit/a07e8cdae7727583e20c9dec632a376365a6e209.diff LOG: [clang-tidy] fix false positive in lambda expr for return-const-ref-from-parameter (#118990) We should bind the node in `hasAncestor` matcher and `equalsBoundNode` in the other matcher because `hasAncestor` will visit the ancestor until to find the matched result. Added: Modified: clang-tools-extra/clang-tidy/bugprone/ReturnConstRefFromParameterCheck.cpp clang-tools-extra/docs/ReleaseNotes.rst clang-tools-extra/test/clang-tidy/checkers/bugprone/return-const-ref-from-parameter.cpp Removed: ################################################################################ diff --git a/clang-tools-extra/clang-tidy/bugprone/ReturnConstRefFromParameterCheck.cpp b/clang-tools-extra/clang-tidy/bugprone/ReturnConstRefFromParameterCheck.cpp index a35fcd99d494af5..295955a971d7e87 100644 --- a/clang-tools-extra/clang-tidy/bugprone/ReturnConstRefFromParameterCheck.cpp +++ b/clang-tools-extra/clang-tidy/bugprone/ReturnConstRefFromParameterCheck.cpp @@ -31,22 +31,20 @@ void ReturnConstRefFromParameterCheck::registerMatchers(MatchFinder *Finder) { qualType(lValueReferenceType(pointee( qualType(isConstQualified())))) .bind("type"))), - hasDeclContext(functionDecl().bind("owner")), + hasDeclContext(functionDecl( + equalsBoundNode("func"), + hasReturnTypeLoc(loc(qualType( + hasCanonicalType(equalsBoundNode("type"))))))), unless(hasLifetimeBoundAttr())) .bind("param"))) .bind("dref")); - const auto Func = - functionDecl(equalsBoundNode("owner"), - hasReturnTypeLoc(loc( - qualType(hasCanonicalType(equalsBoundNode("type")))))) - .bind("func"); Finder->addMatcher( returnStmt( + hasAncestor(functionDecl().bind("func")), hasReturnValue(anyOf( DRef, ignoringParens(conditionalOperator(eachOf( - hasTrueExpression(DRef), hasFalseExpression(DRef)))))), - hasAncestor(Func)), + hasTrueExpression(DRef), hasFalseExpression(DRef))))))), this); } diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst index e00f86f7d01447f..b2b66dca6ccf853 100644 --- a/clang-tools-extra/docs/ReleaseNotes.rst +++ b/clang-tools-extra/docs/ReleaseNotes.rst @@ -183,8 +183,8 @@ Changes in existing checks - Improved :doc:`bugprone-return-const-ref-from-parameter <clang-tidy/checks/bugprone/return-const-ref-from-parameter>` check to diagnose potential dangling references when returning a ``const &`` parameter - by using the conditional operator ``cond ? var1 : var2`` and no longer giving - false positives for functions which contain lambda and ignore parameters + by using the conditional operator ``cond ? var1 : var2`` and fixing false + positives for functions which contain lambda and ignore parameters with ``[[clang::lifetimebound]]`` attribute. - Improved :doc:`bugprone-sizeof-expression diff --git a/clang-tools-extra/test/clang-tidy/checkers/bugprone/return-const-ref-from-parameter.cpp b/clang-tools-extra/test/clang-tidy/checkers/bugprone/return-const-ref-from-parameter.cpp index 46cb9063beda976..a3297ca0f8084e9 100644 --- a/clang-tools-extra/test/clang-tidy/checkers/bugprone/return-const-ref-from-parameter.cpp +++ b/clang-tools-extra/test/clang-tidy/checkers/bugprone/return-const-ref-from-parameter.cpp @@ -203,3 +203,26 @@ namespace use_lifetime_bound_attr { int const &f(int const &a [[clang::lifetimebound]]) { return a; } } // namespace use_lifetime_bound_attr } // namespace gh117696 + + +namespace lambda { +using T = const int &; +using K = const float &; +T inner_valid_lambda(T a) { + [&]() -> T { return a; }; + return a; + // CHECK-MESSAGES: :[[@LINE-1]]:10: warning: returning a constant reference parameter +} +T inner_invalid_lambda(T a) { + [&](T a) -> T { return a; }; + // CHECK-MESSAGES: :[[@LINE-1]]:26: warning: returning a constant reference parameter + return a; + // CHECK-MESSAGES: :[[@LINE-1]]:10: warning: returning a constant reference parameter +} +T inner_invalid_lambda2(T a) { + [&](K a) -> K { return a; }; + // CHECK-MESSAGES: :[[@LINE-1]]:26: warning: returning a constant reference parameter + return a; + // CHECK-MESSAGES: :[[@LINE-1]]:10: warning: returning a constant reference parameter +} +} // namespace lambda _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
