Author: Abhinav Pradeep Date: 2026-06-02T09:08:18+02:00 New Revision: c22474fc02c1c26c81577d4cc147ed3b7c04a079
URL: https://github.com/llvm/llvm-project/commit/c22474fc02c1c26c81577d4cc147ed3b7c04a079 DIFF: https://github.com/llvm/llvm-project/commit/c22474fc02c1c26c81577d4cc147ed3b7c04a079.diff LOG: [LifetimeSafety] Prevent false-negative lifetimebound verification when origin escapes in an unrelated manner (#200786) This PR removes a false-negative `[[lifetimebound]]` verification result that occurs when the annotated attribute escapes via unrelated origin escape kinds (escape through global, escape through field). Change summary: - `Checker.cpp` has function `checkAnnotations` which checks if an escaping `Origin` was an annotated parameter. Modified the logic there to only verify `[[lifetimebound]]` in the case that the escape was through a return statement. Fixes #200412 --------- Signed-off-by: Abhinav Pradeep <[email protected]> Added: Modified: clang/lib/Analysis/LifetimeSafety/Checker.cpp clang/test/Sema/warn-lifetime-safety-lifetimebound.cpp Removed: ################################################################################ diff --git a/clang/lib/Analysis/LifetimeSafety/Checker.cpp b/clang/lib/Analysis/LifetimeSafety/Checker.cpp index d6d4ec6b5617e..2a71b5eb9a934 100644 --- a/clang/lib/Analysis/LifetimeSafety/Checker.cpp +++ b/clang/lib/Analysis/LifetimeSafety/Checker.cpp @@ -134,7 +134,8 @@ class LifetimeChecker { return; if (PVD->hasAttr<LifetimeBoundAttr>()) { // Track that this lifetimebound parameter correctly escapes. - VerifiedLiftimeboundEscapes.insert(PVD); + if (isa<ReturnEscapeFact>(OEF)) + VerifiedLiftimeboundEscapes.insert(PVD); } else { // Otherwise, suggest lifetimebound for parameter escaping through // return or a field in constructor. @@ -148,10 +149,12 @@ class LifetimeChecker { // field! }; auto CheckImplicitThis = [&](const CXXMethodDecl *MD) { - if (implicitObjectParamIsLifetimeBound(MD)) - VerifiedLiftimeboundEscapes.insert(MD); - else if (auto *ReturnEsc = dyn_cast<ReturnEscapeFact>(OEF)) - AnnotationWarningsMap.try_emplace(MD, ReturnEsc->getReturnExpr()); + if (auto *ReturnEsc = dyn_cast<ReturnEscapeFact>(OEF)) { + if (implicitObjectParamIsLifetimeBound(MD)) + VerifiedLiftimeboundEscapes.insert(MD); + else + AnnotationWarningsMap.try_emplace(MD, ReturnEsc->getReturnExpr()); + } }; auto MovedAtEscape = MovedLoans.getMovedLoans(OEF); for (LoanID LID : EscapedLoans) { diff --git a/clang/test/Sema/warn-lifetime-safety-lifetimebound.cpp b/clang/test/Sema/warn-lifetime-safety-lifetimebound.cpp index 5e22677f5269d..b0320bcbf4334 100644 --- a/clang/test/Sema/warn-lifetime-safety-lifetimebound.cpp +++ b/clang/test/Sema/warn-lifetime-safety-lifetimebound.cpp @@ -44,6 +44,24 @@ View return_alias_through_unannotated_passthrough( return not_lb(alias); } +View global_view; + +View assign_param_to_global( + const MyObj &obj [[clang::lifetimebound]]) { // expected-warning {{could not verify that the return value can be lifetime bound to 'obj'}} + global_view = obj; // Wrong kind of escape. + return View(); // Unrelated view. +} + +struct EnclosingState { + View member; + + View assign_param_to_field( + const MyObj &obj [[clang::lifetimebound]]) { // expected-warning {{could not verify that the return value can be lifetime bound to 'obj'}} + member = obj; // Wrong kind of escape. + return View(); // Unrelated view. + } +}; + View not_lb_view(View v); View lb_view(View v [[clang::lifetimebound]]); _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
