[Sema] Mark array element destructors referenced during initialization

This fixes a crash where we would neglect to mark a destructor referenced for an
__attribute__((no_destory)) array. The destructor is needed though, since if an
exception is thrown we need to cleanup the elements.

rdar://48462498

Differential revision: https://reviews.llvm.org/D61165

llvm-svn: 360446

3 files changed, 52 insertions, 53 deletions

diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index fac7d418d40..afd50f1438e 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -13098,12 +13098,17 @@ void Sema::FinalizeVarWithDestructor(VarDecl *VD, const RecordType *Record) {
     return;
 
   CXXDestructorDecl *Destructor = LookupDestructor(ClassDecl);
-  MarkFunctionReferenced(VD->getLocation(), Destructor);
-  CheckDestructorAccess(VD->getLocation(), Destructor,
-                        PDiag(diag::err_access_dtor_var)
-                        << VD->getDeclName()
-                        << VD->getType());
-  DiagnoseUseOfDecl(Destructor, VD->getLocation());
+
+  // If this is an array, we'll require the destructor during initialization, so
+  // we can skip over this. We still want to emit exit-time destructor warnings
+  // though.
+  if (!VD->getType()->isArrayType()) {
+    MarkFunctionReferenced(VD->getLocation(), Destructor);
+    CheckDestructorAccess(VD->getLocation(), Destructor,
+                          PDiag(diag::err_access_dtor_var)
+                              << VD->getDeclName() << VD->getType());
+    DiagnoseUseOfDecl(Destructor, VD->getLocation());
+  }
 
   if (Destructor->isTrivial()) return;
   if (!VD->hasGlobalStorage()) return;
diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp
index b256dc655fe..8f00887ebc4 100644
--- a/clang/lib/Sema/SemaExprCXX.cpp
+++ b/clang/lib/Sema/SemaExprCXX.cpp
@@ -2200,24 +2200,6 @@ Sema::BuildCXXNew(SourceRange Range, bool UseGlobal,
     MarkFunctionReferenced(StartLoc, OperatorDelete);
   }
 
-  // C++0x [expr.new]p17:
-  //   If the new expression creates an array of objects of class type,
-  //   access and ambiguity control are done for the destructor.
-  QualType BaseAllocType = Context.getBaseElementType(AllocType);
-  if (ArraySize && !BaseAllocType->isDependentType()) {
-    if (const RecordType *BaseRecordType = BaseAllocType->getAs<RecordType>()) {
-      if (CXXDestructorDecl *dtor = LookupDestructor(
-              cast<CXXRecordDecl>(BaseRecordType->getDecl()))) {
-        MarkFunctionReferenced(StartLoc, dtor);
-        CheckDestructorAccess(StartLoc, dtor,
-                              PDiag(diag::err_access_dtor)
-                                << BaseAllocType);
-        if (DiagnoseUseOfDecl(dtor, StartLoc))
-          return ExprError();
-      }
-    }
-  }
-
   return CXXNewExpr::Create(Context, UseGlobal, OperatorNew, OperatorDelete,
                             PassAlignment, UsualArrayDeleteWantsSize,
                             PlacementArgs, TypeIdParens, ArraySize, initStyle,
diff --git a/clang/lib/Sema/SemaInit.cpp b/clang/lib/Sema/SemaInit.cpp
index 8bcce39c5ef..45456aff364 100644
--- a/clang/lib/Sema/SemaInit.cpp
+++ b/clang/lib/Sema/SemaInit.cpp
@@ -1707,6 +1707,30 @@ void InitListChecker::CheckVectorType(const InitializedEntity &Entity,
   }
 }
 
+/// Check if the type of a class element has an accessible destructor, and marks
+/// it referenced. Returns true if we shouldn't form a reference to the
+/// destructor.
+///
+/// Aggregate initialization requires a class element's destructor be
+/// accessible per 11.6.1 [dcl.init.aggr]:
+///
+/// The destructor for each element of class type is potentially invoked
+/// (15.4 [class.dtor]) from the context where the aggregate initialization
+/// occurs.
+static bool checkDestructorReference(QualType ElementType, SourceLocation Loc,
+                                     Sema &SemaRef) {
+  auto *CXXRD = ElementType->getAsCXXRecordDecl();
+  if (!CXXRD)
+    return false;
+
+  CXXDestructorDecl *Destructor = SemaRef.LookupDestructor(CXXRD);
+  SemaRef.CheckDestructorAccess(Loc, Destructor,
+                                SemaRef.PDiag(diag::err_access_dtor_temp)
+                                << ElementType);
+  SemaRef.MarkFunctionReferenced(Loc, Destructor);
+  return SemaRef.DiagnoseUseOfDecl(Destructor, Loc);
+}
+
 void InitListChecker::CheckArrayType(const InitializedEntity &Entity,
                                      InitListExpr *IList, QualType &DeclType,
                                      llvm::APSInt elementIndex,
@@ -1716,6 +1740,14 @@ void InitListChecker::CheckArrayType(const InitializedEntity &Entity,
                                      unsigned &StructuredIndex) {
   const ArrayType *arrayType = SemaRef.Context.getAsArrayType(DeclType);
 
+  if (!VerifyOnly) {
+    if (checkDestructorReference(arrayType->getElementType(),
+                                 IList->getEndLoc(), SemaRef)) {
+      hadError = true;
+      return;
+    }
+  }
+
   // Check for the special-case of initializing an array with a string.
   if (Index < IList->getNumInits()) {
     if (IsStringInit(IList->getInit(Index), arrayType, SemaRef.Context) ==
@@ -1877,30 +1909,6 @@ bool InitListChecker::CheckFlexibleArrayInit(const InitializedEntity &Entity,
   return FlexArrayDiag != diag::ext_flexible_array_init;
 }
 
-/// Check if the type of a class element has an accessible destructor.
-///
-/// Aggregate initialization requires a class element's destructor be
-/// accessible per 11.6.1 [dcl.init.aggr]:
-///
-/// The destructor for each element of class type is potentially invoked
-/// (15.4 [class.dtor]) from the context where the aggregate initialization
-/// occurs.
-static bool hasAccessibleDestructor(QualType ElementType, SourceLocation Loc,
-                                    Sema &SemaRef) {
-  auto *CXXRD = ElementType->getAsCXXRecordDecl();
-  if (!CXXRD)
-    return false;
-
-  CXXDestructorDecl *Destructor = SemaRef.LookupDestructor(CXXRD);
-  SemaRef.CheckDestructorAccess(Loc, Destructor,
-                                SemaRef.PDiag(diag::err_access_dtor_temp)
-                                    << ElementType);
-  SemaRef.MarkFunctionReferenced(Loc, Destructor);
-  if (SemaRef.DiagnoseUseOfDecl(Destructor, Loc))
-    return true;
-  return false;
-}
-
 void InitListChecker::CheckStructUnionTypes(
     const InitializedEntity &Entity, InitListExpr *IList, QualType DeclType,
     CXXRecordDecl::base_class_range Bases, RecordDecl::field_iterator Field,
@@ -1924,7 +1932,7 @@ void InitListChecker::CheckStructUnionTypes(
     if (!VerifyOnly)
       for (FieldDecl *FD : RD->fields()) {
         QualType ET = SemaRef.Context.getBaseElementType(FD->getType());
-        if (hasAccessibleDestructor(ET, IList->getEndLoc(), SemaRef)) {
+        if (checkDestructorReference(ET, IList->getEndLoc(), SemaRef)) {
           hadError = true;
           return;
         }
@@ -1984,7 +1992,7 @@ void InitListChecker::CheckStructUnionTypes(
     }
 
     if (!VerifyOnly)
-      if (hasAccessibleDestructor(Base.getType(), InitLoc, SemaRef)) {
+      if (checkDestructorReference(Base.getType(), InitLoc, SemaRef)) {
         hadError = true;
         return;
       }
@@ -2026,7 +2034,7 @@ void InitListChecker::CheckStructUnionTypes(
         while (std::next(F) != Field)
           ++F;
         QualType ET = SemaRef.Context.getBaseElementType(F->getType());
-        if (hasAccessibleDestructor(ET, InitLoc, SemaRef)) {
+        if (checkDestructorReference(ET, InitLoc, SemaRef)) {
           hadError = true;
           return;
         }
@@ -2075,7 +2083,7 @@ void InitListChecker::CheckStructUnionTypes(
 
     if (!VerifyOnly) {
       QualType ET = SemaRef.Context.getBaseElementType(Field->getType());
-      if (hasAccessibleDestructor(ET, InitLoc, SemaRef)) {
+      if (checkDestructorReference(ET, InitLoc, SemaRef)) {
         hadError = true;
         return;
       }
@@ -2131,7 +2139,7 @@ void InitListChecker::CheckStructUnionTypes(
                                                      : Field;
     for (RecordDecl::field_iterator E = RD->field_end(); I != E; ++I) {
       QualType ET = SemaRef.Context.getBaseElementType(I->getType());
-      if (hasAccessibleDestructor(ET, IList->getEndLoc(), SemaRef)) {
+      if (checkDestructorReference(ET, IList->getEndLoc(), SemaRef)) {
         hadError = true;
         return;
       }
@@ -6325,6 +6333,10 @@ PerformConstructorInitialization(Sema &S,
   if (S.DiagnoseUseOfDecl(Step.Function.FoundDecl, Loc))
     return ExprError();
 
+  if (const ArrayType *AT = S.Context.getAsArrayType(Entity.getType()))
+    if (checkDestructorReference(S.Context.getBaseElementType(AT), Loc, S))
+      return ExprError();
+
   if (shouldBindAsTemporary(Entity))
     CurInit = S.MaybeBindToTemporary(CurInit.get());