Implement an additional fix for infinite recursion of deleted special

member functions by making sure that they're on the record before
checking for deletion.

Also make sure source locations are valid to avoid crashes.

Unfortunately, the declare-all-implicit-members approach is still
required in order to ensure that dependency loops do not result in
incorrectly deleting functions (since they are to be deleted at the
declaration point per the standard).

Fixes PR9917

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@131520 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 63 insertions, 58 deletions

diff --git a/lib/Sema/SemaDeclCXX.cpp b/lib/Sema/SemaDeclCXX.cpp
index f1b03ff9c7..9f146e9254 100644
--- a/lib/Sema/SemaDeclCXX.cpp
+++ b/lib/Sema/SemaDeclCXX.cpp
@@ -3293,6 +3293,8 @@ bool Sema::ShouldDeleteDefaultConstructor(CXXConstructorDecl *CD) {
   if (!LangOpts.CPlusPlus0x)
     return false;
 
+  SourceLocation Loc = CD->getLocation();
+
   // Do access control from the constructor
   ContextRAII CtorContext(*this, CD);
 
@@ -3324,7 +3326,7 @@ bool Sema::ShouldDeleteDefaultConstructor(CXXConstructorDecl *CD) {
     CXXDestructorDecl *BaseDtor = LookupDestructor(BaseDecl);
     if (BaseDtor->isDeleted())
       return true;
-    if (CheckDestructorAccess(SourceLocation(), BaseDtor, PDiag()) !=
+    if (CheckDestructorAccess(Loc, BaseDtor, PDiag()) !=
         AR_accessible)
       return true;
 
@@ -3335,8 +3337,7 @@ bool Sema::ShouldDeleteDefaultConstructor(CXXConstructorDecl *CD) {
     InitializedEntity BaseEntity =
       InitializedEntity::InitializeBase(Context, BI, 0);
     InitializationKind Kind =
-      InitializationKind::CreateDirect(SourceLocation(), SourceLocation(),
-                                       SourceLocation());
+      InitializationKind::CreateDirect(Loc, Loc, Loc);
 
     InitializationSequence InitSeq(*this, BaseEntity, Kind, 0, 0);
 
@@ -3355,7 +3356,7 @@ bool Sema::ShouldDeleteDefaultConstructor(CXXConstructorDecl *CD) {
     CXXDestructorDecl *BaseDtor = LookupDestructor(BaseDecl);
     if (BaseDtor->isDeleted())
       return true;
-    if (CheckDestructorAccess(SourceLocation(), BaseDtor, PDiag()) !=
+    if (CheckDestructorAccess(Loc, BaseDtor, PDiag()) !=
         AR_accessible)
       return true;
 
@@ -3366,8 +3367,7 @@ bool Sema::ShouldDeleteDefaultConstructor(CXXConstructorDecl *CD) {
     InitializedEntity BaseEntity =
       InitializedEntity::InitializeBase(Context, BI, BI);
     InitializationKind Kind =
-      InitializationKind::CreateDirect(SourceLocation(), SourceLocation(),
-                                       SourceLocation());
+      InitializationKind::CreateDirect(Loc, Loc, Loc);
 
     InitializationSequence InitSeq(*this, BaseEntity, Kind, 0, 0);
 
@@ -3400,7 +3400,7 @@ bool Sema::ShouldDeleteDefaultConstructor(CXXConstructorDecl *CD) {
       CXXDestructorDecl *FieldDtor = LookupDestructor(FieldRecord);
       if (FieldDtor->isDeleted())
         return true;
-      if (CheckDestructorAccess(SourceLocation(), FieldDtor, PDiag()) !=
+      if (CheckDestructorAccess(Loc, FieldDtor, PDiag()) !=
           AR_accessible)
         return true;
 
@@ -3444,8 +3444,7 @@ bool Sema::ShouldDeleteDefaultConstructor(CXXConstructorDecl *CD) {
     InitializedEntity MemberEntity =
       InitializedEntity::InitializeMember(*FI, 0);
     InitializationKind Kind = 
-      InitializationKind::CreateDirect(SourceLocation(), SourceLocation(),
-                                       SourceLocation());
+      InitializationKind::CreateDirect(Loc, Loc, Loc);
     
     InitializationSequence InitSeq(*this, MemberEntity, Kind, 0, 0);
 
@@ -3467,6 +3466,8 @@ bool Sema::ShouldDeleteCopyConstructor(CXXConstructorDecl *CD) {
   if (!LangOpts.CPlusPlus0x)
     return false;
 
+  SourceLocation Loc = CD->getLocation();
+
   // Do access control from the constructor
   ContextRAII CtorContext(*this, CD);
 
@@ -3503,7 +3504,7 @@ bool Sema::ShouldDeleteCopyConstructor(CXXConstructorDecl *CD) {
     CXXDestructorDecl *BaseDtor = LookupDestructor(BaseDecl);
     if (BaseDtor->isDeleted())
       return true;
-    if (CheckDestructorAccess(SourceLocation(), BaseDtor, PDiag()) !=
+    if (CheckDestructorAccess(Loc, BaseDtor, PDiag()) !=
         AR_accessible)
       return true;
 
@@ -3514,15 +3515,13 @@ bool Sema::ShouldDeleteCopyConstructor(CXXConstructorDecl *CD) {
     InitializedEntity BaseEntity =
       InitializedEntity::InitializeBase(Context, BI, 0);
     InitializationKind Kind =
-      InitializationKind::CreateDirect(SourceLocation(), SourceLocation(),
-                                       SourceLocation());
+      InitializationKind::CreateDirect(Loc, Loc, Loc);
 
     // Construct a fake expression to perform the copy overloading.
     QualType ArgType = BaseType.getUnqualifiedType();
     if (ConstArg)
       ArgType.addConst();
-    Expr *Arg = new (Context) OpaqueValueExpr(SourceLocation(), ArgType,
-                                              VK_LValue);
+    Expr *Arg = new (Context) OpaqueValueExpr(Loc, ArgType, VK_LValue);
 
     InitializationSequence InitSeq(*this, BaseEntity, Kind, &Arg, 1);
 
@@ -3542,7 +3541,7 @@ bool Sema::ShouldDeleteCopyConstructor(CXXConstructorDecl *CD) {
     CXXDestructorDecl *BaseDtor = LookupDestructor(BaseDecl);
     if (BaseDtor->isDeleted())
       return true;
-    if (CheckDestructorAccess(SourceLocation(), BaseDtor, PDiag()) !=
+    if (CheckDestructorAccess(Loc, BaseDtor, PDiag()) !=
         AR_accessible)
       return true;
 
@@ -3553,15 +3552,13 @@ bool Sema::ShouldDeleteCopyConstructor(CXXConstructorDecl *CD) {
     InitializedEntity BaseEntity =
       InitializedEntity::InitializeBase(Context, BI, BI);
     InitializationKind Kind =
-      InitializationKind::CreateDirect(SourceLocation(), SourceLocation(),
-                                       SourceLocation());
+      InitializationKind::CreateDirect(Loc, Loc, Loc);
 
     // Construct a fake expression to perform the copy overloading.
     QualType ArgType = BaseType.getUnqualifiedType();
     if (ConstArg)
       ArgType.addConst();
-    Expr *Arg = new (Context) OpaqueValueExpr(SourceLocation(), ArgType,
-                                              VK_LValue);
+    Expr *Arg = new (Context) OpaqueValueExpr(Loc, ArgType, VK_LValue);
 
     InitializationSequence InitSeq(*this, BaseEntity, Kind, &Arg, 1);
 
@@ -3614,7 +3611,7 @@ bool Sema::ShouldDeleteCopyConstructor(CXXConstructorDecl *CD) {
         CXXDestructorDecl *FieldDtor = LookupDestructor(FieldRecord);
         if (FieldDtor->isDeleted())
           return true;
-        if (CheckDestructorAccess(SourceLocation(), FieldDtor, PDiag()) !=
+        if (CheckDestructorAccess(Loc, FieldDtor, PDiag()) !=
             AR_accessible)
           return true;
       }
@@ -3630,8 +3627,7 @@ bool Sema::ShouldDeleteCopyConstructor(CXXConstructorDecl *CD) {
     }
 
     InitializationKind Kind = 
-      InitializationKind::CreateDirect(SourceLocation(), SourceLocation(),
-                                       SourceLocation());
+      InitializationKind::CreateDirect(Loc, Loc, Loc);
  
     // Construct a fake expression to perform the copy overloading.
     QualType ArgType = FieldType;
@@ -3639,8 +3635,7 @@ bool Sema::ShouldDeleteCopyConstructor(CXXConstructorDecl *CD) {
       ArgType = ArgType->getPointeeType();
     else if (ConstArg)
       ArgType.addConst();
-    Expr *Arg = new (Context) OpaqueValueExpr(SourceLocation(), ArgType,
-                                              VK_LValue);
+    Expr *Arg = new (Context) OpaqueValueExpr(Loc, ArgType, VK_LValue);
    
     InitializationSequence InitSeq(*this, Entities.back(), Kind, &Arg, 1);
 
@@ -3657,6 +3652,8 @@ bool Sema::ShouldDeleteCopyAssignmentOperator(CXXMethodDecl *MD) {
   if (!LangOpts.CPlusPlus0x)
     return false;
 
+  SourceLocation Loc = MD->getLocation();
+
   // Do access control from the constructor
   ContextRAII MethodContext(*this, MD);
 
@@ -3672,7 +3669,7 @@ bool Sema::ShouldDeleteCopyAssignmentOperator(CXXMethodDecl *MD) {
 
   DeclarationName OperatorName =
     Context.DeclarationNames.getCXXOperatorName(OO_Equal);
-  LookupResult R(*this, OperatorName, SourceLocation(), LookupOrdinaryName);
+  LookupResult R(*this, OperatorName, Loc, LookupOrdinaryName);
   R.suppressDiagnostics();
 
   // FIXME: We should put some diagnostic logic right into this function.
@@ -3716,18 +3713,16 @@ bool Sema::ShouldDeleteCopyAssignmentOperator(CXXMethodDecl *MD) {
     QualType ThisType = BaseType;
     if (ConstArg)
       ArgType.addConst();
-    Expr *Args[] = { new (Context) OpaqueValueExpr(SourceLocation(), ThisType,
-                                                   VK_LValue)
-                   , new (Context) OpaqueValueExpr(SourceLocation(), ArgType,
-                                                   VK_LValue)
+    Expr *Args[] = { new (Context) OpaqueValueExpr(Loc, ThisType, VK_LValue)
+                   , new (Context) OpaqueValueExpr(Loc, ArgType, VK_LValue)
                    };
 
-    OverloadCandidateSet OCS((SourceLocation()));
+    OverloadCandidateSet OCS((Loc));
     OverloadCandidateSet::iterator Best;
 
     AddFunctionCandidates(R.asUnresolvedSet(), Args, 2, OCS);
 
-    if (OCS.BestViableFunction(*this, SourceLocation(), Best, false) !=
+    if (OCS.BestViableFunction(*this, Loc, Best, false) !=
         OR_Success)
       return true;
   }
@@ -3763,18 +3758,16 @@ bool Sema::ShouldDeleteCopyAssignmentOperator(CXXMethodDecl *MD) {
     QualType ThisType = BaseType;
     if (ConstArg)
       ArgType.addConst();
-    Expr *Args[] = { new (Context) OpaqueValueExpr(SourceLocation(), ThisType,
-                                                   VK_LValue)
-                   , new (Context) OpaqueValueExpr(SourceLocation(), ArgType,
-                                                   VK_LValue)
+    Expr *Args[] = { new (Context) OpaqueValueExpr(Loc, ThisType, VK_LValue)
+                   , new (Context) OpaqueValueExpr(Loc, ArgType, VK_LValue)
                    };
 
-    OverloadCandidateSet OCS((SourceLocation()));
+    OverloadCandidateSet OCS((Loc));
     OverloadCandidateSet::iterator Best;
 
     AddFunctionCandidates(R.asUnresolvedSet(), Args, 2, OCS);
 
-    if (OCS.BestViableFunction(*this, SourceLocation(), Best, false) !=
+    if (OCS.BestViableFunction(*this, Loc, Best, false) !=
         OR_Success)
       return true;
   }
@@ -3841,18 +3834,16 @@ bool Sema::ShouldDeleteCopyAssignmentOperator(CXXMethodDecl *MD) {
       QualType ThisType = FieldType;
       if (ConstArg)
         ArgType.addConst();
-      Expr *Args[] = { new (Context) OpaqueValueExpr(SourceLocation(), ThisType,
-                                                     VK_LValue)
-                     , new (Context) OpaqueValueExpr(SourceLocation(), ArgType,
-                                                     VK_LValue)
+      Expr *Args[] = { new (Context) OpaqueValueExpr(Loc, ThisType, VK_LValue)
+                     , new (Context) OpaqueValueExpr(Loc, ArgType, VK_LValue)
                      };
 
-      OverloadCandidateSet OCS((SourceLocation()));
+      OverloadCandidateSet OCS((Loc));
       OverloadCandidateSet::iterator Best;
 
       AddFunctionCandidates(R.asUnresolvedSet(), Args, 2, OCS);
 
-      if (OCS.BestViableFunction(*this, SourceLocation(), Best, false) !=
+      if (OCS.BestViableFunction(*this, Loc, Best, false) !=
           OR_Success)
         return true;
     }
@@ -3867,6 +3858,8 @@ bool Sema::ShouldDeleteDestructor(CXXDestructorDecl *DD) {
   if (!LangOpts.CPlusPlus0x)
     return false;
 
+  SourceLocation Loc = DD->getLocation();
+
   // Do access control from the destructor
   ContextRAII CtorContext(*this, DD);
 
@@ -3894,7 +3887,7 @@ bool Sema::ShouldDeleteDestructor(CXXDestructorDecl *DD) {
     //    a destructor that is inaccessible from the defaulted destructor
     if (BaseDtor->isDeleted())
       return true;
-    if (CheckDestructorAccess(SourceLocation(), BaseDtor, PDiag()) !=
+    if (CheckDestructorAccess(Loc, BaseDtor, PDiag()) !=
         AR_accessible)
       return true;
   }
@@ -3910,7 +3903,7 @@ bool Sema::ShouldDeleteDestructor(CXXDestructorDecl *DD) {
     //    a destructor that is inaccessible from the defaulted destructor
     if (BaseDtor->isDeleted())
       return true;
-    if (CheckDestructorAccess(SourceLocation(), BaseDtor, PDiag()) !=
+    if (CheckDestructorAccess(Loc, BaseDtor, PDiag()) !=
         AR_accessible)
       return true;
   }
@@ -3944,7 +3937,7 @@ bool Sema::ShouldDeleteDestructor(CXXDestructorDecl *DD) {
         //    inaccessible from the defaulted destructor
         if (FieldDtor->isDeleted())
           return true;
-        if (CheckDestructorAccess(SourceLocation(), FieldDtor, PDiag()) !=
+        if (CheckDestructorAccess(Loc, FieldDtor, PDiag()) !=
           AR_accessible)
         return true;
         
@@ -3960,7 +3953,7 @@ bool Sema::ShouldDeleteDestructor(CXXDestructorDecl *DD) {
     FunctionDecl *OperatorDelete = 0;
     DeclarationName Name =
       Context.DeclarationNames.getCXXOperatorName(OO_Delete);
-    if (FindDeallocationFunction(SourceLocation(), RD, Name, OperatorDelete,
+    if (FindDeallocationFunction(Loc, RD, Name, OperatorDelete,
           false))
       return true;
   }
@@ -5997,15 +5990,13 @@ CXXConstructorDecl *Sema::DeclareImplicitDefaultConstructor(
   
   // Note that we have declared this constructor.
   ++ASTContext::NumImplicitDefaultConstructorsDeclared;
-
-  // Do not delete this yet if we're in a template
-  if (!ClassDecl->isDependentType() &&
-      ShouldDeleteDefaultConstructor(DefaultCon))
-    DefaultCon->setDeletedAsWritten();
   
   if (Scope *S = getScopeForContext(ClassDecl))
     PushOnScopeChains(DefaultCon, S, false);
   ClassDecl->addDecl(DefaultCon);
+
+  if (ShouldDeleteDefaultConstructor(DefaultCon))
+    DefaultCon->setDeletedAsWritten();
   
   return DefaultCon;
 }
@@ -6706,14 +6697,14 @@ CXXMethodDecl *Sema::DeclareImplicitCopyAssignment(CXXRecordDecl *ClassDecl) {
   
   // Note that we have added this copy-assignment operator.
   ++ASTContext::NumImplicitCopyAssignmentOperatorsDeclared;
-  
-  if (ShouldDeleteCopyAssignmentOperator(CopyAssignment))
-    CopyAssignment->setDeletedAsWritten();
 
   if (Scope *S = getScopeForContext(ClassDecl))
     PushOnScopeChains(CopyAssignment, S, false);
   ClassDecl->addDecl(CopyAssignment);
   
+  if (ShouldDeleteCopyAssignmentOperator(CopyAssignment))
+    CopyAssignment->setDeletedAsWritten();
+  
   AddOverriddenMethods(ClassDecl, CopyAssignment);
   return CopyAssignment;
 }
@@ -7187,12 +7178,12 @@ CXXConstructorDecl *Sema::DeclareImplicitCopyConstructor(
                                                SC_None, 0);
   CopyConstructor->setParams(&FromParam, 1);
 
-  if (ShouldDeleteCopyConstructor(CopyConstructor))
-    CopyConstructor->setDeletedAsWritten();
-
   if (Scope *S = getScopeForContext(ClassDecl))
     PushOnScopeChains(CopyConstructor, S, false);
   ClassDecl->addDecl(CopyConstructor);
+
+  if (ShouldDeleteCopyConstructor(CopyConstructor))
+    CopyConstructor->setDeletedAsWritten();
   
   return CopyConstructor;
 }
diff --git a/test/SemaCXX/defaulted-ctor-loop.cpp b/test/SemaCXX/defaulted-ctor-loop.cpp
new file mode 100644
index 0000000000..6a41972cf7
--- /dev/null
+++ b/test/SemaCXX/defaulted-ctor-loop.cpp
@@ -0,0 +1,14 @@
+// RUN: %clang_cc1 -fsyntax-only -verify -std=c++0x %s
+
+// WARNING: This test may recurse infinitely if failing.
+
+struct foo;
+struct bar {
+  bar(foo&);
+};
+struct foo {
+  bar b;
+  foo()
+    : b(b) // expected-warning{{field is uninitialized}}
+  {}
+};