Author: Haojian Wu Date: 2025-02-17T14:40:31+01:00 New Revision: 9c49b188b8e1434eb774ee8422124ad3e8870dce
URL: https://github.com/llvm/llvm-project/commit/9c49b188b8e1434eb774ee8422124ad3e8870dce DIFF: https://github.com/llvm/llvm-project/commit/9c49b188b8e1434eb774ee8422124ad3e8870dce.diff LOG: [clang] Fix false positive regression for lifetime analysis warning. (#127460) This fixes a false positive caused by #114044. For `GSLPointer*` types, it's less clear whether the lifetime issue is about the GSLPointer object itself or the owner it points to. To avoid false positives, we take a conservative approach in our heuristic. Fixes #127195 (This will be backported to release 20). Added: Modified: clang/lib/Sema/CheckExprLifetime.cpp clang/test/Sema/Inputs/lifetime-analysis.h clang/test/Sema/warn-lifetime-analysis-nocfg.cpp Removed: ################################################################################ diff --git a/clang/lib/Sema/CheckExprLifetime.cpp b/clang/lib/Sema/CheckExprLifetime.cpp index 8963cad86dbca..1f87001f35b57 100644 --- a/clang/lib/Sema/CheckExprLifetime.cpp +++ b/clang/lib/Sema/CheckExprLifetime.cpp @@ -1239,11 +1239,12 @@ static AnalysisResult analyzePathForGSLPointer(const IndirectLocalPath &Path, } // Check the return type, e.g. // const GSLOwner& func(const Foo& foo [[clang::lifetimebound]]) + // GSLOwner* func(cosnt Foo& foo [[clang::lifetimebound]]) // GSLPointer func(const Foo& foo [[clang::lifetimebound]]) if (FD && - ((FD->getReturnType()->isReferenceType() && + ((FD->getReturnType()->isPointerOrReferenceType() && isRecordWithAttr<OwnerAttr>(FD->getReturnType()->getPointeeType())) || - isPointerLikeType(FD->getReturnType()))) + isGLSPointerType(FD->getReturnType()))) return Report; return Abandon; diff --git a/clang/test/Sema/Inputs/lifetime-analysis.h b/clang/test/Sema/Inputs/lifetime-analysis.h index d318033ff0cc4..2072e4603cead 100644 --- a/clang/test/Sema/Inputs/lifetime-analysis.h +++ b/clang/test/Sema/Inputs/lifetime-analysis.h @@ -61,6 +61,7 @@ struct basic_string_view { basic_string_view(); basic_string_view(const T *); const T *begin() const; + const T *data() const; }; using string_view = basic_string_view<char>; @@ -80,6 +81,7 @@ struct basic_string { const T *c_str() const; operator basic_string_view<T> () const; using const_iterator = iter<T>; + const T *data() const; }; using string = basic_string<char>; diff --git a/clang/test/Sema/warn-lifetime-analysis-nocfg.cpp b/clang/test/Sema/warn-lifetime-analysis-nocfg.cpp index 04bb1330ded4c..66a2a19ceb321 100644 --- a/clang/test/Sema/warn-lifetime-analysis-nocfg.cpp +++ b/clang/test/Sema/warn-lifetime-analysis-nocfg.cpp @@ -852,3 +852,27 @@ struct Test { }; } // namespace GH120543 + +namespace GH127195 { +template <typename T> +struct StatusOr { + T* operator->() [[clang::lifetimebound]]; + T* value() [[clang::lifetimebound]]; +}; + +const char* foo() { + StatusOr<std::string> s; + return s->data(); // expected-warning {{address of stack memory associated with local variable}} + + StatusOr<std::string_view> s2; + return s2->data(); + + StatusOr<StatusOr<std::string_view>> s3; + return s3.value()->value()->data(); + + // FIXME: nested cases are not supported now. + StatusOr<StatusOr<std::string>> s4; + return s4.value()->value()->data(); +} + +} // namespace GH127195 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
