https://github.com/vbvictor created https://github.com/llvm/llvm-project/pull/181699
Closes https://github.com/llvm/llvm-project/issues/180344. >From cced057ff7dcb6505cb9532bf19e87192fe011be Mon Sep 17 00:00:00 2001 From: Victor Baranov <[email protected]> Date: Mon, 16 Feb 2026 19:36:07 +0300 Subject: [PATCH] [LifetimeSafety] Correctly place lifetimebound attr in corner cases --- clang/lib/Sema/AnalysisBasedWarnings.cpp | 32 +++++++++++++++---- .../test/Sema/warn-lifetime-safety-fixits.cpp | 24 ++++++++++++++ .../Sema/warn-lifetime-safety-suggestions.cpp | 31 ++++++++++++++++++ 3 files changed, 81 insertions(+), 6 deletions(-) diff --git a/clang/lib/Sema/AnalysisBasedWarnings.cpp b/clang/lib/Sema/AnalysisBasedWarnings.cpp index 8c7bff27718de..5c49e601840cf 100644 --- a/clang/lib/Sema/AnalysisBasedWarnings.cpp +++ b/clang/lib/Sema/AnalysisBasedWarnings.cpp @@ -2937,10 +2937,16 @@ class LifetimeSafetySemaHelperImpl : public LifetimeSafetySemaHelper { : diag::warn_lifetime_safety_intra_tu_param_suggestion; SourceLocation InsertionPoint = Lexer::getLocForEndOfToken( ParmToAnnotate->getEndLoc(), 0, S.getSourceManager(), S.getLangOpts()); + StringRef FixItText = " [[clang::lifetimebound]]"; + if (!ParmToAnnotate->getIdentifier()) { + // For unnamed parameters, placing attributes after the type would be + // parsed as a type attribute, not a parameter attribute. + InsertionPoint = ParmToAnnotate->getBeginLoc(); + FixItText = "[[clang::lifetimebound]] "; + } S.Diag(ParmToAnnotate->getBeginLoc(), DiagID) << ParmToAnnotate->getSourceRange() - << FixItHint::CreateInsertion(InsertionPoint, - " [[clang::lifetimebound]]"); + << FixItHint::CreateInsertion(InsertionPoint, FixItText); S.Diag(EscapeExpr->getBeginLoc(), diag::note_lifetime_safety_suggestion_returned_here) << EscapeExpr->getSourceRange(); @@ -2952,10 +2958,24 @@ class LifetimeSafetySemaHelperImpl : public LifetimeSafetySemaHelper { unsigned DiagID = (Scope == SuggestionScope::CrossTU) ? diag::warn_lifetime_safety_cross_tu_this_suggestion : diag::warn_lifetime_safety_intra_tu_this_suggestion; - SourceLocation InsertionPoint; - InsertionPoint = Lexer::getLocForEndOfToken( - MD->getTypeSourceInfo()->getTypeLoc().getEndLoc(), 0, - S.getSourceManager(), S.getLangOpts()); + const auto MDL = MD->getTypeSourceInfo()->getTypeLoc(); + SourceLocation InsertionPoint = Lexer::getLocForEndOfToken( + MDL.getEndLoc(), 0, S.getSourceManager(), S.getLangOpts()); + if (const auto *FPT = MD->getType()->getAs<FunctionProtoType>(); + FPT && FPT->hasTrailingReturn()) { + // For trailing return types, 'getEndLoc()' includes the return type + // after '->', placing the attribute in an invalid position. + // Instead use 'getLocalRangeEnd()' which gives the '->' location + // for trailing returns, so find the last token before it. + const auto FTL = MDL.getAs<FunctionTypeLoc>(); + assert(FTL); + InsertionPoint = Lexer::getLocForEndOfToken( + Lexer::findPreviousToken(FTL.getLocalRangeEnd(), S.getSourceManager(), + S.getLangOpts(), + /*IncludeComments=*/false) + ->getLocation(), + 0, S.getSourceManager(), S.getLangOpts()); + } S.Diag(InsertionPoint, DiagID) << MD->getNameInfo().getSourceRange() << FixItHint::CreateInsertion(InsertionPoint, diff --git a/clang/test/Sema/warn-lifetime-safety-fixits.cpp b/clang/test/Sema/warn-lifetime-safety-fixits.cpp index 82b36caf8d141..3ae252a9d00f2 100644 --- a/clang/test/Sema/warn-lifetime-safety-fixits.cpp +++ b/clang/test/Sema/warn-lifetime-safety-fixits.cpp @@ -138,3 +138,27 @@ const OutOfLine &OutOfLine::get() const { // CHECK: fix-it:"{{.*}}":{[[@LINE-2]]:40-[[@LINE-2]]:40}:" {{\[\[}}clang::lifetimebound]]" return *this; } + +struct TrailingReturn { + TrailingReturn() {} + ~TrailingReturn() {} + MyObj data; + + auto get_view() -> View { + // CHECK: :[[@LINE-1]]:18: warning: implicit this in intra-TU function should be marked + // CHECK: fix-it:"{{.*}}":{[[@LINE-2]]:18-[[@LINE-2]]:18}:" {{\[\[}}clang::lifetimebound]]" + return data; + } + + auto get_view_const() const -> View { + // CHECK: :[[@LINE-1]]:30: warning: implicit this in intra-TU function should be marked + // CHECK: fix-it:"{{.*}}":{[[@LINE-2]]:30-[[@LINE-2]]:30}:" {{\[\[}}clang::lifetimebound]]" + return data; + } + + auto get_ref() const -> const MyObj & { + // CHECK: :[[@LINE-1]]:23: warning: implicit this in intra-TU function should be marked + // CHECK: fix-it:"{{.*}}":{[[@LINE-2]]:23-[[@LINE-2]]:23}:" {{\[\[}}clang::lifetimebound]]" + return data; + } +}; diff --git a/clang/test/Sema/warn-lifetime-safety-suggestions.cpp b/clang/test/Sema/warn-lifetime-safety-suggestions.cpp index 0ed545d06ca8a..1887b2f257226 100644 --- a/clang/test/Sema/warn-lifetime-safety-suggestions.cpp +++ b/clang/test/Sema/warn-lifetime-safety-suggestions.cpp @@ -50,6 +50,9 @@ inline View redeclared_in_header(View a) { // expected-warning {{parameter in i return a; // expected-note {{param returned here}} } +View return_unnamed_view(View); // expected-warning {{parameter in cross-TU function should be marked [[clang::lifetimebound]]}} +MyObj& return_unnamed_ref(MyObj&, bool); // expected-warning {{parameter in cross-TU function should be marked [[clang::lifetimebound]]}} + struct ReturnThis { const ReturnThis& get() const; // expected-warning {{implicit this in cross-TU function should be marked [[clang::lifetimebound]]}}. }; @@ -90,6 +93,14 @@ MyObj* return_pointer_object(MyObj* a) { return a; // expected-note {{param returned here}} } +View return_unnamed_view(View a) { + return a; // expected-note {{param returned here}} +} + +MyObj& return_unnamed_ref(MyObj& a, bool c) { + return a; // expected-note {{param returned here}} +} + MyObj& return_reference(MyObj& a, // expected-warning {{parameter in intra-TU function should be marked [[clang::lifetimebound]]}} MyObj& b, // expected-warning {{parameter in intra-TU function should be marked [[clang::lifetimebound]]}} bool c) { @@ -344,6 +355,26 @@ MyObj* test_template_inference_with_stack() { } } // namespace inference_with_templates +namespace trailing_return { +struct TrailingReturn { + TrailingReturn() {} + ~TrailingReturn() {} + MyObj data; + + auto get_view() -> View { // expected-warning {{implicit this in intra-TU function should be marked [[clang::lifetimebound]]}} + return data; // expected-note {{param returned here}} + } + + auto get_view_const() const -> View { // expected-warning {{implicit this in intra-TU function should be marked [[clang::lifetimebound]]}} + return data; // expected-note {{param returned here}} + } + + auto get_ref() const -> const MyObj& { // expected-warning {{implicit this in intra-TU function should be marked [[clang::lifetimebound]]}} + return data; // expected-note {{param returned here}} + } +}; +} // namespace trailing_return + //===----------------------------------------------------------------------===// // Negative Test Cases //===----------------------------------------------------------------------===// _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
