Fix the desugaring of dependent decltype and typeof(expr) nodes. The

isSugared() and desugar() routines previously provided were never
actually called, since the corresponding types
(DependentTypeOfExprType, DependentDecltypeType) don't have
corresponding type classes. Outside of the current (incomplete) patch
I'm working on, I haven't found a way to trigger this problem.

llvm-svn: 134973

2 files changed, 20 insertions, 10 deletions

diff --git a/clang/include/clang/AST/Type.h b/clang/include/clang/AST/Type.h
index f1710f0e973..d8a92272c86 100644
--- a/clang/include/clang/AST/Type.h
+++ b/clang/include/clang/AST/Type.h
@@ -2952,7 +2952,7 @@ public:
   QualType desugar() const;
 
   /// \brief Returns whether this type directly provides sugar.
-  bool isSugared() const { return true; }
+  bool isSugared() const;
 
   static bool classof(const Type *T) { return T->getTypeClass() == TypeOfExpr; }
   static bool classof(const TypeOfExprType *) { return true; }
@@ -2972,9 +2972,6 @@ public:
   DependentTypeOfExprType(const ASTContext &Context, Expr *E)
     : TypeOfExprType(E), Context(Context) { }
 
-  bool isSugared() const { return false; }
-  QualType desugar() const { return QualType(this, 0); }
-
   void Profile(llvm::FoldingSetNodeID &ID) {
     Profile(ID, Context, getUnderlyingExpr());
   }
@@ -3025,10 +3022,10 @@ public:
   QualType getUnderlyingType() const { return UnderlyingType; }
 
   /// \brief Remove a single level of sugar.
-  QualType desugar() const { return getUnderlyingType(); }
+  QualType desugar() const;
 
   /// \brief Returns whether this type directly provides sugar.
-  bool isSugared() const { return !isDependentType(); }
+  bool isSugared() const;
 
   static bool classof(const Type *T) { return T->getTypeClass() == Decltype; }
   static bool classof(const DecltypeType *) { return true; }
@@ -3046,9 +3043,6 @@ class DependentDecltypeType : public DecltypeType, public llvm::FoldingSetNode {
 public:
   DependentDecltypeType(const ASTContext &Context, Expr *E);
 
-  bool isSugared() const { return false; }
-  QualType desugar() const { return QualType(this, 0); }
-
   void Profile(llvm::FoldingSetNodeID &ID) {
     Profile(ID, Context, getUnderlyingExpr());
   }
diff --git a/clang/lib/AST/Type.cpp b/clang/lib/AST/Type.cpp
index 20a0d595e41..89c00eb8507 100644
--- a/clang/lib/AST/Type.cpp
+++ b/clang/lib/AST/Type.cpp
@@ -1645,8 +1645,15 @@ TypeOfExprType::TypeOfExprType(Expr *E, QualType can)
     TOExpr(E) {
 }
 
+bool TypeOfExprType::isSugared() const {
+  return !TOExpr->isTypeDependent();
+}
+
 QualType TypeOfExprType::desugar() const {
-  return getUnderlyingExpr()->getType();
+  if (isSugared())
+    return getUnderlyingExpr()->getType();
+  
+  return QualType(this, 0);
 }
 
 void DependentTypeOfExprType::Profile(llvm::FoldingSetNodeID &ID,
@@ -1663,6 +1670,15 @@ DecltypeType::DecltypeType(Expr *E, QualType underlyingType, QualType can)
   UnderlyingType(underlyingType) {
 }
 
+bool DecltypeType::isSugared() const { return !E->isInstantiationDependent(); }
+
+QualType DecltypeType::desugar() const {
+  if (isSugared())
+    return getUnderlyingType();
+  
+  return QualType(this, 0);
+}
+
 DependentDecltypeType::DependentDecltypeType(const ASTContext &Context, Expr *E)
   : DecltypeType(E, Context.DependentTy), Context(Context) { }