4 files changed, 44 insertions, 23 deletions

diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index 10f875b1b76..d7ebedf72a0 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -1522,11 +1522,12 @@ QualType ASTContext::getDependentSizedArrayType(QualType EltTy,
   DependentSizedArrayType *Canon = 0;
   llvm::FoldingSetNodeID ID;
 
+  QualType CanonicalEltTy = getCanonicalType(EltTy);
   if (NumElts) {
     // Dependently-sized array types that do not have a specified
     // number of elements will have their sizes deduced from an
     // initializer.
-    DependentSizedArrayType::Profile(ID, *this, getCanonicalType(EltTy), ASM,
+    DependentSizedArrayType::Profile(ID, *this, CanonicalEltTy, ASM,
                                      EltTypeQuals, NumElts);
 
     Canon = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
@@ -1539,28 +1540,28 @@ QualType ASTContext::getDependentSizedArrayType(QualType EltTy,
     New = new (*this, TypeAlignment)
       DependentSizedArrayType(*this, EltTy, QualType(Canon, 0),
                               NumElts, ASM, EltTypeQuals, Brackets);
-  } else {
-    QualType CanonEltTy = getCanonicalType(EltTy);
-    if (CanonEltTy == EltTy) {
-      New = new (*this, TypeAlignment)
-        DependentSizedArrayType(*this, EltTy, QualType(),
-                                NumElts, ASM, EltTypeQuals, Brackets);
-
-      if (NumElts) {
-        DependentSizedArrayType *CanonCheck
-          = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
-        assert(!CanonCheck && "Dependent-sized canonical array type broken");
-        (void)CanonCheck;
-        DependentSizedArrayTypes.InsertNode(New, InsertPos);
-      }
-    } else {
-      QualType Canon = getDependentSizedArrayType(CanonEltTy, NumElts,
-                                                  ASM, EltTypeQuals,
-                                                  SourceRange());
-      New = new (*this, TypeAlignment)
-        DependentSizedArrayType(*this, EltTy, Canon,
-                                NumElts, ASM, EltTypeQuals, Brackets);
+  } else if (CanonicalEltTy == EltTy) {
+    // This is a canonical type. Record it.
+    New = new (*this, TypeAlignment)
+      DependentSizedArrayType(*this, EltTy, QualType(),
+                              NumElts, ASM, EltTypeQuals, Brackets);
+    
+    if (NumElts) {
+#ifndef NDEBUG
+      DependentSizedArrayType *CanonCheck
+        = DependentSizedArrayTypes.FindNodeOrInsertPos(ID, InsertPos);
+      assert(!CanonCheck && "Dependent-sized canonical array type broken");
+      (void)CanonCheck;
+#endif
+      DependentSizedArrayTypes.InsertNode(New, InsertPos);
     }
+  } else {
+    QualType Canon = getDependentSizedArrayType(CanonicalEltTy, NumElts,
+                                                ASM, EltTypeQuals,
+                                                SourceRange());
+    New = new (*this, TypeAlignment)
+      DependentSizedArrayType(*this, EltTy, Canon,
+                              NumElts, ASM, EltTypeQuals, Brackets);
   }
 
   Types.push_back(New);
diff --git a/clang/lib/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp
index 38e786bff10..c0aff9afde3 100644
--- a/clang/lib/Serialization/ASTReader.cpp
+++ b/clang/lib/Serialization/ASTReader.cpp
@@ -2764,6 +2764,8 @@ QualType ASTReader::ReadTypeRecord(unsigned Index) {
     }
     TypedefDecl *Decl = cast<TypedefDecl>(GetDecl(Record[0]));
     QualType Canonical = GetType(Record[1]);
+    if (!Canonical.isNull())
+      Canonical = Context->getCanonicalType(Canonical);
     return Context->getTypedefType(Decl, Canonical);
   }
 
@@ -2867,6 +2869,8 @@ QualType ASTReader::ReadTypeRecord(unsigned Index) {
     NestedNameSpecifier *NNS = ReadNestedNameSpecifier(Record, Idx);
     const IdentifierInfo *Name = this->GetIdentifierInfo(Record, Idx);
     QualType Canon = GetType(Record[Idx++]);
+    if (!Canon.isNull())
+      Canon = Context->getCanonicalType(Canon);
     return Context->getDependentNameType(Keyword, NNS, Name, Canon);
   }
 
diff --git a/clang/test/PCH/cxx-templates.cpp b/clang/test/PCH/cxx-templates.cpp
index d36d5449c81..95477992e67 100644
--- a/clang/test/PCH/cxx-templates.cpp
+++ b/clang/test/PCH/cxx-templates.cpp
@@ -17,7 +17,7 @@ struct A {
   static T my_templf(T x) { return x; }
 };
 
-void test() {
+void test(const int (&a6)[17]) {
   int x = templ_f<int, 5>(3);
   
   S<char, float>::templ();
@@ -32,6 +32,8 @@ void test() {
   s3.m();
 
   TS5 ts(0);
+
+  S6<const int[17]>::t2 b6 = a6;
 }
 
 template struct S4<int>;
diff --git a/clang/test/PCH/cxx-templates.h b/clang/test/PCH/cxx-templates.h
index e1f285b19dc..5baa772b5d0 100644
--- a/clang/test/PCH/cxx-templates.h
+++ b/clang/test/PCH/cxx-templates.h
@@ -150,3 +150,17 @@ struct TS5 {
 template<class T> void f_PR8134(T);
 template<class T> void f_PR8134(T);
 void g_PR8134() { f_PR8134(0); f_PR8134('x'); }
+
+// rdar8580149
+template <typename T>
+struct S6;
+
+template <typename T, unsigned N>
+struct S6<const T [N]>
+{
+private:
+   typedef const T t1[N];
+public:
+   typedef t1& t2;
+};
+