llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang Author: Arseniy Zaostrovnykh (necto) <details> <summary>Changes</summary> If a mutex interface is split in inheritance chain, e.g. struct mutex has `unlock` and inherits `lock` from __mutex_base then calls m.lock() and m.unlock() have different "this" targets: m and the __mutex_base of m, which used to confuse the `ActiveCritSections` list. Taking base region canonicalizes the region used to identify a critical section and enables search in ActiveCritSections list regardless of which class the callee is the member of. This possibly fixes #<!-- -->104241 CPP-5541 --- Full diff: https://github.com/llvm/llvm-project/pull/106240.diff 2 Files Affected: - (modified) clang/lib/StaticAnalyzer/Checkers/BlockInCriticalSectionChecker.cpp (+4-2) - (modified) clang/test/Analysis/block-in-critical-section-inheritance.cpp (+10) ``````````diff diff --git a/clang/lib/StaticAnalyzer/Checkers/BlockInCriticalSectionChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/BlockInCriticalSectionChecker.cpp index 4cd2f2802f30cd..52ff639c6b8022 100644 --- a/clang/lib/StaticAnalyzer/Checkers/BlockInCriticalSectionChecker.cpp +++ b/clang/lib/StaticAnalyzer/Checkers/BlockInCriticalSectionChecker.cpp @@ -245,8 +245,10 @@ static const MemRegion *getRegion(const CallEvent &Call, const MutexDescriptor &Descriptor, bool IsLock) { return std::visit( - [&Call, IsLock](auto &&Descriptor) { - return Descriptor.getRegion(Call, IsLock); + [&Call, IsLock](auto &Descr) -> const MemRegion * { + if (const MemRegion *Reg = Descr.getRegion(Call, IsLock)) + return Reg->getBaseRegion(); + return nullptr; }, Descriptor); } diff --git a/clang/test/Analysis/block-in-critical-section-inheritance.cpp b/clang/test/Analysis/block-in-critical-section-inheritance.cpp index db20df8c60a5c9..c60ba2632cee25 100644 --- a/clang/test/Analysis/block-in-critical-section-inheritance.cpp +++ b/clang/test/Analysis/block-in-critical-section-inheritance.cpp @@ -29,3 +29,13 @@ void gh_99628() { // expected-note@-2 {{Call to blocking function 'sleep' inside of critical section}} m.unlock(); } + +void no_false_positive_gh_104241() { + std::mutex m; + m.lock(); + // If inheritance not handled properly, this unlock might not match the lock + // above because technically they act on different memory regions: + // __mutex_base and mutex. + m.unlock(); + sleep(10); // no-warning +} `````````` </details> https://github.com/llvm/llvm-project/pull/106240 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
