Author: Fabian Wolff Date: 2021-12-01T15:28:01-05:00 New Revision: 844a8d3cecb4cc40e5d9694bcf111518910ea2ff
URL: https://github.com/llvm/llvm-project/commit/844a8d3cecb4cc40e5d9694bcf111518910ea2ff DIFF: https://github.com/llvm/llvm-project/commit/844a8d3cecb4cc40e5d9694bcf111518910ea2ff.diff LOG: Fix false positives in `fuchsia-trailing-return` check involving deduction guides Fixes PR#47614. Deduction guides, implicit or user-defined, look like function declarations in the AST. They aren't really functions, though, and they always have a trailing return type, so it doesn't make sense to issue this warning for them. Added: Modified: clang-tools-extra/clang-tidy/fuchsia/TrailingReturnCheck.cpp clang-tools-extra/docs/ReleaseNotes.rst clang-tools-extra/test/clang-tidy/checkers/fuchsia-trailing-return.cpp Removed: ################################################################################ diff --git a/clang-tools-extra/clang-tidy/fuchsia/TrailingReturnCheck.cpp b/clang-tools-extra/clang-tidy/fuchsia/TrailingReturnCheck.cpp index 4ade4767190ef..2902e34fe860f 100644 --- a/clang-tools-extra/clang-tidy/fuchsia/TrailingReturnCheck.cpp +++ b/clang-tools-extra/clang-tidy/fuchsia/TrailingReturnCheck.cpp @@ -17,12 +17,6 @@ namespace clang { namespace tidy { namespace fuchsia { -namespace { -AST_MATCHER(FunctionDecl, hasTrailingReturn) { - return Node.getType()->castAs<FunctionProtoType>()->hasTrailingReturn(); -} -} // namespace - void TrailingReturnCheck::registerMatchers(MatchFinder *Finder) { // Functions that have trailing returns are disallowed, except for those // using decltype specifiers and lambda with otherwise unutterable @@ -30,15 +24,16 @@ void TrailingReturnCheck::registerMatchers(MatchFinder *Finder) { Finder->addMatcher( functionDecl(hasTrailingReturn(), unless(anyOf(returns(decltypeType()), - hasParent(cxxRecordDecl(isLambda()))))) + hasParent(cxxRecordDecl(isLambda())), + cxxDeductionGuideDecl()))) .bind("decl"), this); } void TrailingReturnCheck::check(const MatchFinder::MatchResult &Result) { - if (const auto *D = Result.Nodes.getNodeAs<Decl>("decl")) + if (const auto *D = Result.Nodes.getNodeAs<FunctionDecl>("decl")) diag(D->getBeginLoc(), - "a trailing return type is disallowed for this type of declaration"); + "a trailing return type is disallowed for this function declaration"); } } // namespace fuchsia diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst index fa03d7eac99e0..8991bac7c1f8a 100644 --- a/clang-tools-extra/docs/ReleaseNotes.rst +++ b/clang-tools-extra/docs/ReleaseNotes.rst @@ -140,6 +140,9 @@ Changes in existing checks <clang-tidy/checks/google-readability-casting>` to diagnose and fix functional casts, to achieve feature parity with the corresponding ``cpplint.py`` check. +- Fixed a false positive in :doc:`fuchsia-trailing-return + <clang-tidy/checks/fuchsia-trailing-return>` for C++17 deduction guides. + Removed checks ^^^^^^^^^^^^^^ diff --git a/clang-tools-extra/test/clang-tidy/checkers/fuchsia-trailing-return.cpp b/clang-tools-extra/test/clang-tidy/checkers/fuchsia-trailing-return.cpp index f6c943ac873e7..14c4452e4fdc2 100644 --- a/clang-tools-extra/test/clang-tidy/checkers/fuchsia-trailing-return.cpp +++ b/clang-tools-extra/test/clang-tidy/checkers/fuchsia-trailing-return.cpp @@ -1,9 +1,9 @@ -// RUN: %check_clang_tidy %s fuchsia-trailing-return %t +// RUN: %check_clang_tidy -std=c++17-or-later %s fuchsia-trailing-return %t int add_one(const int arg) { return arg; } auto get_add_one() -> int (*)(const int) { - // CHECK-MESSAGES: [[@LINE-1]]:1: warning: a trailing return type is disallowed for this type of declaration + // CHECK-MESSAGES: [[@LINE-1]]:1: warning: a trailing return type is disallowed for this function declaration // CHECK-NEXT: auto get_add_one() -> int (*)(const int) { return add_one; } @@ -21,3 +21,31 @@ template <typename T1, typename T2> auto fn(const T1 &lhs, const T2 &rhs) -> decltype(lhs + rhs) { return lhs + rhs; } + +// Now check that implicit and explicit C++17 deduction guides don't trigger this warning (PR#47614). + +template <typename T> +struct ImplicitDeductionGuides { + ImplicitDeductionGuides(const T &); +}; + +template <typename A, typename B> +struct pair { + A first; + B second; +}; + +template <typename T> +struct UserDefinedDeductionGuides { + UserDefinedDeductionGuides(T); + template <typename T1, typename T2> + UserDefinedDeductionGuides(T1, T2); +}; + +template <typename T1, typename T2> +UserDefinedDeductionGuides(T1, T2) -> UserDefinedDeductionGuides<pair<T1, T2>>; + +void foo() { + ImplicitDeductionGuides X(42); + UserDefinedDeductionGuides s(1, "abc"); +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
