https://github.com/usx95 updated https://github.com/llvm/llvm-project/pull/170843
>From cf5322832037f0fdc98b0ce802708b811babe707 Mon Sep 17 00:00:00 2001 From: Utkarsh Saxena <[email protected]> Date: Fri, 5 Dec 2025 11:58:46 +0000 Subject: [PATCH 1/2] false-posiitve thread-safety --- clang/lib/Analysis/ThreadSafety.cpp | 7 +++++++ .../test/SemaCXX/warn-thread-safety-analysis.cpp | 16 ++++++++++++++++ 2 files changed, 23 insertions(+) diff --git a/clang/lib/Analysis/ThreadSafety.cpp b/clang/lib/Analysis/ThreadSafety.cpp index a25bd6007d5ed..417a951d9c99f 100644 --- a/clang/lib/Analysis/ThreadSafety.cpp +++ b/clang/lib/Analysis/ThreadSafety.cpp @@ -43,6 +43,7 @@ #include "llvm/ADT/SmallVector.h" #include "llvm/ADT/StringRef.h" #include "llvm/Support/Allocator.h" +#include "llvm/Support/Casting.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/TrailingObjects.h" #include "llvm/Support/raw_ostream.h" @@ -2820,6 +2821,12 @@ void ThreadSafetyAnalyzer::runAnalysis(AnalysisDeclContext &AC) { case CFGElement::AutomaticObjectDtor: { CFGAutomaticObjDtor AD = BI.castAs<CFGAutomaticObjDtor>(); const auto *DD = AD.getDestructorDecl(AC.getASTContext()); + // Ignore dtor for parameters as the corresponding constructor does + // not happen in the callee context but in the caller context. It is + // not possible to know which constuctor was used for its construction + // so avoid reading the destructor as well. + if (isa_and_nonnull<ParmVarDecl>(AD.getVarDecl())) + break; if (!DD || !DD->hasAttrs()) break; diff --git a/clang/test/SemaCXX/warn-thread-safety-analysis.cpp b/clang/test/SemaCXX/warn-thread-safety-analysis.cpp index 0e91639a271c5..d03493cceeb85 100644 --- a/clang/test/SemaCXX/warn-thread-safety-analysis.cpp +++ b/clang/test/SemaCXX/warn-thread-safety-analysis.cpp @@ -7622,3 +7622,19 @@ void testLoopConditionalReassignment(Foo *f1, Foo *f2, bool cond) { ptr->mu.Unlock(); // expected-warning{{releasing mutex 'ptr->mu' that was not held}} } // expected-warning{{mutex 'f1->mu' is still held at the end of function}} } // namespace CapabilityAliases + +namespace test_function_param_lock_unlock { +class A { + public: + A() EXCLUSIVE_LOCK_FUNCTION(mu_) { + mu_.Lock(); + } + ~A() UNLOCK_FUNCTION(mu_) { mu_.Unlock(); } + private: + Mutex mu_; +}; + +int do_something(A a) { + return 0; +} +} // namespace test_function_param_lock_unlock >From ac7fddb93be1249f1b91b5d5bcb9fa64ae02f02c Mon Sep 17 00:00:00 2001 From: Utkarsh Saxena <[email protected]> Date: Fri, 5 Dec 2025 12:11:06 +0000 Subject: [PATCH 2/2] Add more tests --- clang/lib/Analysis/ThreadSafety.cpp | 5 +---- .../SemaCXX/warn-thread-safety-analysis.cpp | 19 +++++++++++++------ 2 files changed, 14 insertions(+), 10 deletions(-) diff --git a/clang/lib/Analysis/ThreadSafety.cpp b/clang/lib/Analysis/ThreadSafety.cpp index 417a951d9c99f..12bcf2a78821e 100644 --- a/clang/lib/Analysis/ThreadSafety.cpp +++ b/clang/lib/Analysis/ThreadSafety.cpp @@ -2821,10 +2821,7 @@ void ThreadSafetyAnalyzer::runAnalysis(AnalysisDeclContext &AC) { case CFGElement::AutomaticObjectDtor: { CFGAutomaticObjDtor AD = BI.castAs<CFGAutomaticObjDtor>(); const auto *DD = AD.getDestructorDecl(AC.getASTContext()); - // Ignore dtor for parameters as the corresponding constructor does - // not happen in the callee context but in the caller context. It is - // not possible to know which constuctor was used for its construction - // so avoid reading the destructor as well. + // Ignore parameter dtors: their ctors happen in caller context. if (isa_and_nonnull<ParmVarDecl>(AD.getVarDecl())) break; if (!DD || !DD->hasAttrs()) diff --git a/clang/test/SemaCXX/warn-thread-safety-analysis.cpp b/clang/test/SemaCXX/warn-thread-safety-analysis.cpp index d03493cceeb85..203ea424020b6 100644 --- a/clang/test/SemaCXX/warn-thread-safety-analysis.cpp +++ b/clang/test/SemaCXX/warn-thread-safety-analysis.cpp @@ -7626,15 +7626,22 @@ void testLoopConditionalReassignment(Foo *f1, Foo *f2, bool cond) { namespace test_function_param_lock_unlock { class A { public: - A() EXCLUSIVE_LOCK_FUNCTION(mu_) { - mu_.Lock(); - } + A() EXCLUSIVE_LOCK_FUNCTION(mu_) { mu_.Lock(); } ~A() UNLOCK_FUNCTION(mu_) { mu_.Unlock(); } private: Mutex mu_; }; +int do_something(A a) { return 0; } -int do_something(A a) { - return 0; -} +// Unlock in dtor without lock in ctor. +// FIXME: We cannot detect that we are releasing a lock that was never held! +class B { + public: + B() {} + B(int) {} + ~B() UNLOCK_FUNCTION(mu_) { mu_.Unlock(); } + private: + Mutex mu_; +}; +int do_something(B b) { return 0; } } // namespace test_function_param_lock_unlock _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
