llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang-tools-extra Author: Qizhi Hu (jcsxky) <details> <summary>Changes</summary> Try to fix https://github.com/llvm/llvm-project/issues/83845 When `std::forward` is invoked in a function, make sure it uses correct parameter by checking if the bounded `var` equals the parameter. --- Full diff: https://github.com/llvm/llvm-project/pull/83987.diff 3 Files Affected: - (modified) clang-tools-extra/clang-tidy/cppcoreguidelines/MissingStdForwardCheck.cpp (+6-4) - (modified) clang-tools-extra/docs/ReleaseNotes.rst (+2-1) - (modified) clang-tools-extra/test/clang-tidy/checkers/cppcoreguidelines/missing-std-forward.cpp (+10) ``````````diff diff --git a/clang-tools-extra/clang-tidy/cppcoreguidelines/MissingStdForwardCheck.cpp b/clang-tools-extra/clang-tidy/cppcoreguidelines/MissingStdForwardCheck.cpp index c633683570f748..87fd8adf997082 100644 --- a/clang-tools-extra/clang-tidy/cppcoreguidelines/MissingStdForwardCheck.cpp +++ b/clang-tools-extra/clang-tidy/cppcoreguidelines/MissingStdForwardCheck.cpp @@ -112,10 +112,12 @@ void MissingStdForwardCheck::registerMatchers(MatchFinder *Finder) { auto ForwardCallMatcher = callExpr( callExpr().bind("call"), argumentCountIs(1), - hasArgument( - 0, declRefExpr(to( - varDecl(optionally(equalsBoundNode("param"))).bind("var")))), - forCallable(anyOf(equalsBoundNode("func"), CapturedInLambda)), + hasArgument(0, declRefExpr(to(varDecl().bind("var")))), + forCallable( + anyOf(allOf(equalsBoundNode("func"), + functionDecl(hasAnyParameter(parmVarDecl(allOf( + equalsBoundNode("param"), equalsBoundNode("var")))))), + CapturedInLambda)), callee(unresolvedLookupExpr(hasAnyDeclaration( namedDecl(hasUnderlyingDecl(hasName("::std::forward")))))), diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst index 143ae230fc443c..1abe45bae8a84d 100644 --- a/clang-tools-extra/docs/ReleaseNotes.rst +++ b/clang-tools-extra/docs/ReleaseNotes.rst @@ -156,7 +156,8 @@ Changes in existing checks - Improved :doc:`cppcoreguidelines-missing-std-forward <clang-tidy/checks/cppcoreguidelines/missing-std-forward>` check by no longer - giving false positives for deleted functions. + giving false positives for deleted functions and fix false negative when one + parameter is forwarded, but some other parameter isn't. - Cleaned up :doc:`cppcoreguidelines-prefer-member-initializer <clang-tidy/checks/cppcoreguidelines/prefer-member-initializer>` diff --git a/clang-tools-extra/test/clang-tidy/checkers/cppcoreguidelines/missing-std-forward.cpp b/clang-tools-extra/test/clang-tidy/checkers/cppcoreguidelines/missing-std-forward.cpp index 20e43f04180ff3..29af67b60614c8 100644 --- a/clang-tools-extra/test/clang-tidy/checkers/cppcoreguidelines/missing-std-forward.cpp +++ b/clang-tools-extra/test/clang-tidy/checkers/cppcoreguidelines/missing-std-forward.cpp @@ -95,6 +95,16 @@ void lambda_value_capture_copy(T&& t) { [&,t]() { T other = std::forward<T>(t); }; } +template <typename X> +void use(const X &x) {} + +template <typename X, typename Y> +void foo(X &&x, Y &&y) { + // CHECK-MESSAGES: :[[@LINE-1]]:21: warning: forwarding reference parameter 't' is never forwarded inside the function body [cppcoreguidelines-missing-std-forward] + use(std::forward<X>(x)); + use(y); +} + } // namespace positive_cases namespace negative_cases { `````````` </details> https://github.com/llvm/llvm-project/pull/83987 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
