https://github.com/usx95 created https://github.com/llvm/llvm-project/pull/227231
None >From de24554cede3ff267d54c4b2277ac082784847d9 Mon Sep 17 00:00:00 2001 From: Utkarsh Saxena <[email protected]> Date: Tue, 29 Sep 2026 09:09:19 +0000 Subject: [PATCH] capture-by-crash --- .../LifetimeSafety/FactsGenerator.cpp | 11 +++++---- clang/test/Sema/LifetimeSafety/safety.cpp | 23 +++++++++++++++++++ 2 files changed, 29 insertions(+), 5 deletions(-) diff --git a/clang/lib/Analysis/LifetimeSafety/FactsGenerator.cpp b/clang/lib/Analysis/LifetimeSafety/FactsGenerator.cpp index 292e3279233bb..a6726c46f5347 100644 --- a/clang/lib/Analysis/LifetimeSafety/FactsGenerator.cpp +++ b/clang/lib/Analysis/LifetimeSafety/FactsGenerator.cpp @@ -1044,11 +1044,12 @@ void FactsGenerator::handleLifetimeCaptureBy(const FunctionDecl *FD, CapturingArgIdx == LifetimeCaptureByAttr::Unknown || CapturingArgIdx == LifetimeCaptureByAttr::Invalid) continue; - ArrayRef<const Expr *> CallArgs = IsInstance ? Args.drop_front() : Args; - const Expr *CapturedByArg = - (CapturingArgIdx == LifetimeCaptureByAttr::This) - ? Args[0] - : CallArgs[CapturingArgIdx]; + // FIXME: Diagnose bad CapturingArgIdx. + if (CapturingArgIdx != LifetimeCaptureByAttr::This && + (CapturingArgIdx < 0 || + static_cast<size_t>(CapturingArgIdx) >= Args.size())) + continue; + const Expr *CapturedByArg = Args[CapturingArgIdx]; assert(CapturedByArg && "Capturer expression must be valid"); OriginList *Dest = readValue(CapturedByArg); diff --git a/clang/test/Sema/LifetimeSafety/safety.cpp b/clang/test/Sema/LifetimeSafety/safety.cpp index bf49e86577678..fb91fb30713db 100644 --- a/clang/test/Sema/LifetimeSafety/safety.cpp +++ b/clang/test/Sema/LifetimeSafety/safety.cpp @@ -4076,6 +4076,29 @@ void capturing_multiple_locals() { use(v); // expected-note 2 {{later used here}} } +namespace off_by_one_crash { +struct Item { + const int* ptr; +}; + +struct Container { + const Item* saved; +}; + +struct Helper { + void AddItem(const Item& item [[clang::lifetime_capture_by(c)]], + Container& c) const; + void Populate() const { + Container c{}; + { + Item item; + AddItem(item, c); // expected-warning {{local variable 'item' does not live long enough}} + } // expected-note {{local variable 'item' is destroyed here}} + use(c); // expected-note {{later used here}} + } +}; +} // namespace off_by_one_crash + struct [[gsl::Pointer()]] PtrWithInt { int x; }; PtrWithInt f() { return PtrWithInt{10}; _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
