[clang] [clang] Remove the EnableLifetimeWarnings flag in lifetime analysis. (PR #105884)

Haojian Wu via cfe-commits cfe-commits at lists.llvm.org
Mon Aug 26 05:23:01 PDT 2024


https://github.com/hokein updated https://github.com/llvm/llvm-project/pull/105884

>From 0f8a051930491b33181bfc4e27320f0a6f31786c Mon Sep 17 00:00:00 2001
From: Haojian Wu <hokein.wu at gmail.com>
Date: Fri, 23 Aug 2024 21:42:20 +0200
Subject: [PATCH 1/3] [clang] Remove the EnableLifetimeWarnings flag in
 lifetime analysis,

---
 clang/lib/Sema/CheckExprLifetime.cpp          | 156 +++++++-----------
 .../Sema/warn-lifetime-analysis-nocfg.cpp     |  11 ++
 2 files changed, 72 insertions(+), 95 deletions(-)

diff --git a/clang/lib/Sema/CheckExprLifetime.cpp b/clang/lib/Sema/CheckExprLifetime.cpp
index c1362559536962..ef43a0d25e0c9e 100644
--- a/clang/lib/Sema/CheckExprLifetime.cpp
+++ b/clang/lib/Sema/CheckExprLifetime.cpp
@@ -237,13 +237,11 @@ static bool pathContainsInit(IndirectLocalPath &Path) {
 
 static void visitLocalsRetainedByInitializer(IndirectLocalPath &Path,
                                              Expr *Init, LocalVisitor Visit,
-                                             bool RevisitSubinits,
-                                             bool EnableLifetimeWarnings);
+                                             bool RevisitSubinits);
 
 static void visitLocalsRetainedByReferenceBinding(IndirectLocalPath &Path,
                                                   Expr *Init, ReferenceKind RK,
-                                                  LocalVisitor Visit,
-                                                  bool EnableLifetimeWarnings);
+                                                  LocalVisitor Visit);
 
 template <typename T> static bool isRecordWithAttr(QualType Type) {
   if (auto *RD = Type->getAsCXXRecordDecl())
@@ -365,8 +363,7 @@ static bool implicitObjectParamIsLifetimeBound(const FunctionDecl *FD) {
 
 // Visit lifetimebound or gsl-pointer arguments.
 static void visitFunctionCallArguments(IndirectLocalPath &Path, Expr *Call,
-                                       LocalVisitor Visit,
-                                       bool EnableLifetimeWarnings) {
+                                       LocalVisitor Visit) {
   const FunctionDecl *Callee;
   ArrayRef<Expr *> Args;
 
@@ -381,6 +378,8 @@ static void visitFunctionCallArguments(IndirectLocalPath &Path, Expr *Call,
   if (!Callee)
     return;
 
+  bool EnableGSLAnalysis = !Callee->getASTContext().getDiagnostics().isIgnored(
+      diag::warn_dangling_lifetime_pointer, SourceLocation());
   Expr *ObjectArg = nullptr;
   if (isa<CXXOperatorCallExpr>(Call) && Callee->isCXXInstanceMember()) {
     ObjectArg = Args[0];
@@ -393,11 +392,9 @@ static void visitFunctionCallArguments(IndirectLocalPath &Path, Expr *Call,
     Path.push_back({IndirectLocalPathEntry::LifetimeBoundCall, Arg, D});
     if (Arg->isGLValue())
       visitLocalsRetainedByReferenceBinding(Path, Arg, RK_ReferenceBinding,
-                                            Visit,
-                                            /*EnableLifetimeWarnings=*/false);
+                                            Visit);
     else
-      visitLocalsRetainedByInitializer(Path, Arg, Visit, true,
-                                       /*EnableLifetimeWarnings=*/false);
+      visitLocalsRetainedByInitializer(Path, Arg, Visit, true);
     Path.pop_back();
   };
   auto VisitGSLPointerArg = [&](const Decl *D, Expr *Arg, bool Value) {
@@ -408,7 +405,8 @@ static void visitFunctionCallArguments(IndirectLocalPath &Path, Expr *Call,
     // Once we initialized a value with a reference, it can no longer dangle.
     if (!Value) {
       for (const IndirectLocalPathEntry &PE : llvm::reverse(Path)) {
-        if (PE.Kind == IndirectLocalPathEntry::GslReferenceInit)
+        if (PE.Kind == IndirectLocalPathEntry::GslReferenceInit ||
+            PE.Kind == IndirectLocalPathEntry::LifetimeBoundCall)
           continue;
         if (PE.Kind == IndirectLocalPathEntry::GslPointerInit ||
             PE.Kind == IndirectLocalPathEntry::GslPointerAssignment)
@@ -421,11 +419,9 @@ static void visitFunctionCallArguments(IndirectLocalPath &Path, Expr *Call,
                     Arg, D});
     if (Arg->isGLValue())
       visitLocalsRetainedByReferenceBinding(Path, Arg, RK_ReferenceBinding,
-                                            Visit,
-                                            /*EnableLifetimeWarnings=*/true);
+                                            Visit);
     else
-      visitLocalsRetainedByInitializer(Path, Arg, Visit, true,
-                                       /*EnableLifetimeWarnings=*/true);
+      visitLocalsRetainedByInitializer(Path, Arg, Visit, true);
     Path.pop_back();
   };
 
@@ -448,7 +444,7 @@ static void visitFunctionCallArguments(IndirectLocalPath &Path, Expr *Call,
       CheckCoroObjArg = false;
     if (implicitObjectParamIsLifetimeBound(Callee) || CheckCoroObjArg)
       VisitLifetimeBoundArg(Callee, ObjectArg);
-    else if (EnableLifetimeWarnings) {
+    else if (EnableGSLAnalysis) {
       if (auto *CME = dyn_cast<CXXMethodDecl>(Callee);
           CME && shouldTrackImplicitObjectArg(CME))
         VisitGSLPointerArg(Callee, ObjectArg,
@@ -461,15 +457,15 @@ static void visitFunctionCallArguments(IndirectLocalPath &Path, Expr *Call,
        I != N; ++I) {
     if (CheckCoroCall || Callee->getParamDecl(I)->hasAttr<LifetimeBoundAttr>())
       VisitLifetimeBoundArg(Callee->getParamDecl(I), Args[I]);
-    else if (EnableLifetimeWarnings && I == 0) {
+    else if (EnableGSLAnalysis && I == 0) { // GSL
       if (shouldTrackFirstArgument(Callee)) {
         VisitGSLPointerArg(Callee, Args[0],
                            !Callee->getReturnType()->isReferenceType());
-      } else {
-        if (auto *CCE = dyn_cast<CXXConstructExpr>(Call);
-            CCE && CCE->getConstructor()->getParent()->hasAttr<PointerAttr>())
-          VisitGSLPointerArg(CCE->getConstructor()->getParamDecl(0), Args[0],
-                             true);
+      } else if (auto *CCE = dyn_cast<CXXConstructExpr>(Call);
+                 CCE &&
+                 CCE->getConstructor()->getParent()->hasAttr<PointerAttr>()) {
+        VisitGSLPointerArg(CCE->getConstructor()->getParamDecl(0), Args[0],
+                           true);
       }
     }
   }
@@ -479,8 +475,7 @@ static void visitFunctionCallArguments(IndirectLocalPath &Path, Expr *Call,
 /// glvalue expression \c Init.
 static void visitLocalsRetainedByReferenceBinding(IndirectLocalPath &Path,
                                                   Expr *Init, ReferenceKind RK,
-                                                  LocalVisitor Visit,
-                                                  bool EnableLifetimeWarnings) {
+                                                  LocalVisitor Visit) {
   RevertToOldSizeRAII RAII(Path);
 
   // Walk past any constructs which we can lifetime-extend across.
@@ -517,8 +512,7 @@ static void visitLocalsRetainedByReferenceBinding(IndirectLocalPath &Path,
       else
         // We can't lifetime extend through this but we might still find some
         // retained temporaries.
-        return visitLocalsRetainedByInitializer(Path, Init, Visit, true,
-                                                EnableLifetimeWarnings);
+        return visitLocalsRetainedByInitializer(Path, Init, Visit, true);
     }
 
     // Step into CXXDefaultInitExprs so we can diagnose cases where a
@@ -532,21 +526,18 @@ static void visitLocalsRetainedByReferenceBinding(IndirectLocalPath &Path,
 
   if (auto *MTE = dyn_cast<MaterializeTemporaryExpr>(Init)) {
     if (Visit(Path, Local(MTE), RK))
-      visitLocalsRetainedByInitializer(Path, MTE->getSubExpr(), Visit, true,
-                                       EnableLifetimeWarnings);
+      visitLocalsRetainedByInitializer(Path, MTE->getSubExpr(), Visit, true);
   }
 
   if (auto *M = dyn_cast<MemberExpr>(Init)) {
     // Lifetime of a non-reference type field is same as base object.
     if (auto *F = dyn_cast<FieldDecl>(M->getMemberDecl());
         F && !F->getType()->isReferenceType())
-      visitLocalsRetainedByInitializer(Path, M->getBase(), Visit, true,
-                                       EnableLifetimeWarnings);
+      visitLocalsRetainedByInitializer(Path, M->getBase(), Visit, true);
   }
 
   if (isa<CallExpr>(Init))
-    return visitFunctionCallArguments(Path, Init, Visit,
-                                      EnableLifetimeWarnings);
+    return visitFunctionCallArguments(Path, Init, Visit);
 
   switch (Init->getStmtClass()) {
   case Stmt::DeclRefExprClass: {
@@ -565,8 +556,7 @@ static void visitLocalsRetainedByReferenceBinding(IndirectLocalPath &Path,
       } else if (VD->getInit() && !isVarOnPath(Path, VD)) {
         Path.push_back({IndirectLocalPathEntry::VarInit, DRE, VD});
         visitLocalsRetainedByReferenceBinding(Path, VD->getInit(),
-                                              RK_ReferenceBinding, Visit,
-                                              EnableLifetimeWarnings);
+                                              RK_ReferenceBinding, Visit);
       }
     }
     break;
@@ -578,15 +568,13 @@ static void visitLocalsRetainedByReferenceBinding(IndirectLocalPath &Path,
     // handling all sorts of rvalues passed to a unary operator.
     const UnaryOperator *U = cast<UnaryOperator>(Init);
     if (U->getOpcode() == UO_Deref)
-      visitLocalsRetainedByInitializer(Path, U->getSubExpr(), Visit, true,
-                                       EnableLifetimeWarnings);
+      visitLocalsRetainedByInitializer(Path, U->getSubExpr(), Visit, true);
     break;
   }
 
   case Stmt::ArraySectionExprClass: {
-    visitLocalsRetainedByInitializer(Path,
-                                     cast<ArraySectionExpr>(Init)->getBase(),
-                                     Visit, true, EnableLifetimeWarnings);
+    visitLocalsRetainedByInitializer(
+        Path, cast<ArraySectionExpr>(Init)->getBase(), Visit, true);
     break;
   }
 
@@ -594,11 +582,9 @@ static void visitLocalsRetainedByReferenceBinding(IndirectLocalPath &Path,
   case Stmt::BinaryConditionalOperatorClass: {
     auto *C = cast<AbstractConditionalOperator>(Init);
     if (!C->getTrueExpr()->getType()->isVoidType())
-      visitLocalsRetainedByReferenceBinding(Path, C->getTrueExpr(), RK, Visit,
-                                            EnableLifetimeWarnings);
+      visitLocalsRetainedByReferenceBinding(Path, C->getTrueExpr(), RK, Visit);
     if (!C->getFalseExpr()->getType()->isVoidType())
-      visitLocalsRetainedByReferenceBinding(Path, C->getFalseExpr(), RK, Visit,
-                                            EnableLifetimeWarnings);
+      visitLocalsRetainedByReferenceBinding(Path, C->getFalseExpr(), RK, Visit);
     break;
   }
 
@@ -621,8 +607,7 @@ static void visitLocalsRetainedByReferenceBinding(IndirectLocalPath &Path,
 /// the prvalue expression \c Init.
 static void visitLocalsRetainedByInitializer(IndirectLocalPath &Path,
                                              Expr *Init, LocalVisitor Visit,
-                                             bool RevisitSubinits,
-                                             bool EnableLifetimeWarnings) {
+                                             bool RevisitSubinits) {
   RevertToOldSizeRAII RAII(Path);
 
   Expr *Old;
@@ -663,18 +648,16 @@ static void visitLocalsRetainedByInitializer(IndirectLocalPath &Path,
                 if (VD && VD->getType().isConstQualified() && VD->getInit() &&
                     !isVarOnPath(Path, VD)) {
                   Path.push_back({IndirectLocalPathEntry::VarInit, DRE, VD});
-                  visitLocalsRetainedByInitializer(
-                      Path, VD->getInit(), Visit, true, EnableLifetimeWarnings);
+                  visitLocalsRetainedByInitializer(Path, VD->getInit(), Visit,
+                                                   true);
                 }
               } else if (auto *MTE = dyn_cast<MaterializeTemporaryExpr>(L)) {
                 if (MTE->getType().isConstQualified())
                   visitLocalsRetainedByInitializer(Path, MTE->getSubExpr(),
-                                                   Visit, true,
-                                                   EnableLifetimeWarnings);
+                                                   Visit, true);
               }
               return false;
-            },
-            EnableLifetimeWarnings);
+            });
 
         // We assume that objects can be retained by pointers cast to integers,
         // but not if the integer is cast to floating-point type or to _Complex.
@@ -703,9 +686,8 @@ static void visitLocalsRetainedByInitializer(IndirectLocalPath &Path,
         // Model array-to-pointer decay as taking the address of the array
         // lvalue.
         Path.push_back({IndirectLocalPathEntry::AddressOf, CE});
-        return visitLocalsRetainedByReferenceBinding(Path, CE->getSubExpr(),
-                                                     RK_ReferenceBinding, Visit,
-                                                     EnableLifetimeWarnings);
+        return visitLocalsRetainedByReferenceBinding(
+            Path, CE->getSubExpr(), RK_ReferenceBinding, Visit);
 
       default:
         return;
@@ -720,8 +702,7 @@ static void visitLocalsRetainedByInitializer(IndirectLocalPath &Path,
   //   lifetime of the array exactly like binding a reference to a temporary.
   if (auto *ILE = dyn_cast<CXXStdInitializerListExpr>(Init))
     return visitLocalsRetainedByReferenceBinding(Path, ILE->getSubExpr(),
-                                                 RK_StdInitializerList, Visit,
-                                                 EnableLifetimeWarnings);
+                                                 RK_StdInitializerList, Visit);
 
   if (InitListExpr *ILE = dyn_cast<InitListExpr>(Init)) {
     // We already visited the elements of this initializer list while
@@ -732,14 +713,12 @@ static void visitLocalsRetainedByInitializer(IndirectLocalPath &Path,
 
     if (ILE->isTransparent())
       return visitLocalsRetainedByInitializer(Path, ILE->getInit(0), Visit,
-                                              RevisitSubinits,
-                                              EnableLifetimeWarnings);
+                                              RevisitSubinits);
 
     if (ILE->getType()->isArrayType()) {
       for (unsigned I = 0, N = ILE->getNumInits(); I != N; ++I)
         visitLocalsRetainedByInitializer(Path, ILE->getInit(I), Visit,
-                                         RevisitSubinits,
-                                         EnableLifetimeWarnings);
+                                         RevisitSubinits);
       return;
     }
 
@@ -752,14 +731,12 @@ static void visitLocalsRetainedByInitializer(IndirectLocalPath &Path,
       if (RD->isUnion() && ILE->getInitializedFieldInUnion() &&
           ILE->getInitializedFieldInUnion()->getType()->isReferenceType())
         visitLocalsRetainedByReferenceBinding(Path, ILE->getInit(0),
-                                              RK_ReferenceBinding, Visit,
-                                              EnableLifetimeWarnings);
+                                              RK_ReferenceBinding, Visit);
       else {
         unsigned Index = 0;
         for (; Index < RD->getNumBases() && Index < ILE->getNumInits(); ++Index)
           visitLocalsRetainedByInitializer(Path, ILE->getInit(Index), Visit,
-                                           RevisitSubinits,
-                                           EnableLifetimeWarnings);
+                                           RevisitSubinits);
         for (const auto *I : RD->fields()) {
           if (Index >= ILE->getNumInits())
             break;
@@ -768,14 +745,13 @@ static void visitLocalsRetainedByInitializer(IndirectLocalPath &Path,
           Expr *SubInit = ILE->getInit(Index);
           if (I->getType()->isReferenceType())
             visitLocalsRetainedByReferenceBinding(Path, SubInit,
-                                                  RK_ReferenceBinding, Visit,
-                                                  EnableLifetimeWarnings);
+                                                  RK_ReferenceBinding, Visit);
           else
             // This might be either aggregate-initialization of a member or
             // initialization of a std::initializer_list object. Regardless,
             // we should recursively lifetime-extend that initializer.
-            visitLocalsRetainedByInitializer(
-                Path, SubInit, Visit, RevisitSubinits, EnableLifetimeWarnings);
+            visitLocalsRetainedByInitializer(Path, SubInit, Visit,
+                                             RevisitSubinits);
           ++Index;
         }
       }
@@ -796,10 +772,9 @@ static void visitLocalsRetainedByInitializer(IndirectLocalPath &Path,
         Path.push_back({IndirectLocalPathEntry::LambdaCaptureInit, E, &Cap});
       if (E->isGLValue())
         visitLocalsRetainedByReferenceBinding(Path, E, RK_ReferenceBinding,
-                                              Visit, EnableLifetimeWarnings);
+                                              Visit);
       else
-        visitLocalsRetainedByInitializer(Path, E, Visit, true,
-                                         EnableLifetimeWarnings);
+        visitLocalsRetainedByInitializer(Path, E, Visit, true);
       if (Cap.capturesVariable())
         Path.pop_back();
     }
@@ -813,16 +788,14 @@ static void visitLocalsRetainedByInitializer(IndirectLocalPath &Path,
         Expr *Arg = MTE->getSubExpr();
         Path.push_back({IndirectLocalPathEntry::TemporaryCopy, Arg,
                         CCE->getConstructor()});
-        visitLocalsRetainedByInitializer(Path, Arg, Visit, true,
-                                         /*EnableLifetimeWarnings*/ false);
+        visitLocalsRetainedByInitializer(Path, Arg, Visit, true);
         Path.pop_back();
       }
     }
   }
 
   if (isa<CallExpr>(Init) || isa<CXXConstructExpr>(Init))
-    return visitFunctionCallArguments(Path, Init, Visit,
-                                      EnableLifetimeWarnings);
+    return visitFunctionCallArguments(Path, Init, Visit);
 
   switch (Init->getStmtClass()) {
   case Stmt::UnaryOperatorClass: {
@@ -838,8 +811,7 @@ static void visitLocalsRetainedByInitializer(IndirectLocalPath &Path,
 
       Path.push_back({IndirectLocalPathEntry::AddressOf, UO});
       visitLocalsRetainedByReferenceBinding(Path, UO->getSubExpr(),
-                                            RK_ReferenceBinding, Visit,
-                                            EnableLifetimeWarnings);
+                                            RK_ReferenceBinding, Visit);
     }
     break;
   }
@@ -852,11 +824,9 @@ static void visitLocalsRetainedByInitializer(IndirectLocalPath &Path,
       break;
 
     if (BO->getLHS()->getType()->isPointerType())
-      visitLocalsRetainedByInitializer(Path, BO->getLHS(), Visit, true,
-                                       EnableLifetimeWarnings);
+      visitLocalsRetainedByInitializer(Path, BO->getLHS(), Visit, true);
     else if (BO->getRHS()->getType()->isPointerType())
-      visitLocalsRetainedByInitializer(Path, BO->getRHS(), Visit, true,
-                                       EnableLifetimeWarnings);
+      visitLocalsRetainedByInitializer(Path, BO->getRHS(), Visit, true);
     break;
   }
 
@@ -866,11 +836,9 @@ static void visitLocalsRetainedByInitializer(IndirectLocalPath &Path,
     // In C++, we can have a throw-expression operand, which has 'void' type
     // and isn't interesting from a lifetime perspective.
     if (!C->getTrueExpr()->getType()->isVoidType())
-      visitLocalsRetainedByInitializer(Path, C->getTrueExpr(), Visit, true,
-                                       EnableLifetimeWarnings);
+      visitLocalsRetainedByInitializer(Path, C->getTrueExpr(), Visit, true);
     if (!C->getFalseExpr()->getType()->isVoidType())
-      visitLocalsRetainedByInitializer(Path, C->getFalseExpr(), Visit, true,
-                                       EnableLifetimeWarnings);
+      visitLocalsRetainedByInitializer(Path, C->getFalseExpr(), Visit, true);
     break;
   }
 
@@ -972,8 +940,7 @@ static void checkExprLifetimeImpl(Sema &SemaRef,
                                   const InitializedEntity *InitEntity,
                                   const InitializedEntity *ExtendingEntity,
                                   LifetimeKind LK,
-                                  const AssignedEntity *AEntity, Expr *Init,
-                                  bool EnableLifetimeWarnings) {
+                                  const AssignedEntity *AEntity, Expr *Init) {
   assert((AEntity && LK == LK_Assignment) ||
          (InitEntity && LK != LK_Assignment));
   // If this entity doesn't have an interesting lifetime, don't bother looking
@@ -1267,19 +1234,20 @@ static void checkExprLifetimeImpl(Sema &SemaRef,
   };
 
   llvm::SmallVector<IndirectLocalPathEntry, 8> Path;
-  if (EnableLifetimeWarnings && LK == LK_Assignment &&
+  if (!SemaRef.getDiagnostics().isIgnored(diag::warn_dangling_lifetime_pointer,
+                                          SourceLocation()) &&
+      LK == LK_Assignment &&
       isRecordWithAttr<PointerAttr>(AEntity->LHS->getType()))
     Path.push_back({IndirectLocalPathEntry::GslPointerAssignment, Init});
 
   if (Init->isGLValue())
     visitLocalsRetainedByReferenceBinding(Path, Init, RK_ReferenceBinding,
-                                          TemporaryVisitor,
-                                          EnableLifetimeWarnings);
+                                          TemporaryVisitor);
   else
     visitLocalsRetainedByInitializer(
         Path, Init, TemporaryVisitor,
         // Don't revisit the sub inits for the intialization case.
-        /*RevisitSubinits=*/!InitEntity, EnableLifetimeWarnings);
+        /*RevisitSubinits=*/!InitEntity);
 }
 
 void checkExprLifetime(Sema &SemaRef, const InitializedEntity &Entity,
@@ -1287,10 +1255,8 @@ void checkExprLifetime(Sema &SemaRef, const InitializedEntity &Entity,
   auto LTResult = getEntityLifetime(&Entity);
   LifetimeKind LK = LTResult.getInt();
   const InitializedEntity *ExtendingEntity = LTResult.getPointer();
-  bool EnableLifetimeWarnings = !SemaRef.getDiagnostics().isIgnored(
-      diag::warn_dangling_lifetime_pointer, SourceLocation());
   checkExprLifetimeImpl(SemaRef, &Entity, ExtendingEntity, LK,
-                        /*AEntity*/ nullptr, Init, EnableLifetimeWarnings);
+                        /*AEntity*/ nullptr, Init);
 }
 
 void checkExprLifetime(Sema &SemaRef, const AssignedEntity &Entity,
@@ -1306,7 +1272,7 @@ void checkExprLifetime(Sema &SemaRef, const AssignedEntity &Entity,
 
   checkExprLifetimeImpl(SemaRef, /*InitEntity=*/nullptr,
                         /*ExtendingEntity=*/nullptr, LK_Assignment, &Entity,
-                        Init, EnableLifetimeWarnings);
+                        Init);
 }
 
 } // namespace clang::sema
diff --git a/clang/test/Sema/warn-lifetime-analysis-nocfg.cpp b/clang/test/Sema/warn-lifetime-analysis-nocfg.cpp
index cd1904db327105..3cfd9d57eca7a3 100644
--- a/clang/test/Sema/warn-lifetime-analysis-nocfg.cpp
+++ b/clang/test/Sema/warn-lifetime-analysis-nocfg.cpp
@@ -498,4 +498,15 @@ std::string_view test2(int i, std::optional<std::string_view> a) {
     return std::move(*a);
   return std::move(a.value());
 }
+
+struct Foo;
+struct FooView {
+  FooView(const Foo& foo [[clang::lifetimebound]]);
+};
+FooView test3(int i, std::optional<Foo> a) {
+  if (i)
+    return *a; // expected-warning {{address of stack memory}}
+  return a.value(); // expected-warning {{address of stack memory}}
+}
+
 }

>From 8d28136bec2e030eac66a741709078900672e2ce Mon Sep 17 00:00:00 2001
From: Haojian Wu <hokein.wu at gmail.com>
Date: Mon, 26 Aug 2024 12:23:40 +0200
Subject: [PATCH 2/3] remove a comment.

---
 clang/lib/Sema/CheckExprLifetime.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/clang/lib/Sema/CheckExprLifetime.cpp b/clang/lib/Sema/CheckExprLifetime.cpp
index ef43a0d25e0c9e..75359fb81153b1 100644
--- a/clang/lib/Sema/CheckExprLifetime.cpp
+++ b/clang/lib/Sema/CheckExprLifetime.cpp
@@ -457,7 +457,7 @@ static void visitFunctionCallArguments(IndirectLocalPath &Path, Expr *Call,
        I != N; ++I) {
     if (CheckCoroCall || Callee->getParamDecl(I)->hasAttr<LifetimeBoundAttr>())
       VisitLifetimeBoundArg(Callee->getParamDecl(I), Args[I]);
-    else if (EnableGSLAnalysis && I == 0) { // GSL
+    else if (EnableGSLAnalysis && I == 0) {
       if (shouldTrackFirstArgument(Callee)) {
         VisitGSLPointerArg(Callee, Args[0],
                            !Callee->getReturnType()->isReferenceType());

>From 0e81c91d2ff38975f848c8ff6b767ef08e731a81 Mon Sep 17 00:00:00 2001
From: Haojian Wu <hokein.wu at gmail.com>
Date: Mon, 26 Aug 2024 14:22:29 +0200
Subject: [PATCH 3/3] Add tests for #100549

---
 clang/test/Sema/warn-lifetime-analysis-nocfg.cpp | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/clang/test/Sema/warn-lifetime-analysis-nocfg.cpp b/clang/test/Sema/warn-lifetime-analysis-nocfg.cpp
index 3cfd9d57eca7a3..67d1ceaa02d039 100644
--- a/clang/test/Sema/warn-lifetime-analysis-nocfg.cpp
+++ b/clang/test/Sema/warn-lifetime-analysis-nocfg.cpp
@@ -508,5 +508,20 @@ FooView test3(int i, std::optional<Foo> a) {
     return *a; // expected-warning {{address of stack memory}}
   return a.value(); // expected-warning {{address of stack memory}}
 }
+} // namespace GH93386
 
+namespace GH100549 {
+struct UrlAnalyzed {
+  UrlAnalyzed(std::string_view url [[clang::lifetimebound]]);
+};
+std::string StrCat(std::string_view, std::string_view);
+void test1() {
+  UrlAnalyzed url(StrCat("abc", "bcd")); // expected-warning {{object backing the pointer will be destroyed}}
+}
+
+std::string_view ReturnStringView(std::string_view abc [[clang::lifetimebound]]);
+
+void test() {
+  std::string_view svjkk1 = ReturnStringView(StrCat("bar", "x")); // expected-warning {{object backing the pointer will be destroyed at the end of the full-expression}}
 }
+} // namespace GH100549



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