2 files changed, 67 insertions, 12 deletions

diff --git a/lib/Serialization/ASTReaderDecl.cpp b/lib/Serialization/ASTReaderDecl.cpp
index ab46e0a096..6e7cbbf9b0 100644
--- a/lib/Serialization/ASTReaderDecl.cpp
+++ b/lib/Serialization/ASTReaderDecl.cpp
@@ -123,8 +123,8 @@ namespace clang {
                                             ClassTemplateSpecializationDecl *D);
     void VisitClassTemplatePartialSpecializationDecl(
                                      ClassTemplatePartialSpecializationDecl *D);
-    void VisitClassScopeFunctionSpecializationDecl(

-                                       ClassScopeFunctionSpecializationDecl *D);

+    void VisitClassScopeFunctionSpecializationDecl(
+                                       ClassScopeFunctionSpecializationDecl *D);
     void VisitTemplateTypeParmDecl(TemplateTypeParmDecl *D);
     void VisitValueDecl(ValueDecl *VD);
     void VisitEnumConstantDecl(EnumConstantDecl *ECD);
@@ -1087,14 +1087,8 @@ void ASTDeclReader::VisitRedeclarableTemplateDecl(RedeclarableTemplateDecl *D) {
     ASTReader::FirstLatestDeclIDMap::iterator I
         = Reader.FirstLatestDeclIDs.find(ThisDeclID);
     if (I != Reader.FirstLatestDeclIDs.end()) {
-      Decl *NewLatest = Reader.GetDecl(I->second);
-      assert((LatestDecl->getLocation().isInvalid() ||
-              NewLatest->getLocation().isInvalid()  ||
-              !Reader.SourceMgr.isBeforeInTranslationUnit(
-                                                  NewLatest->getLocation(),
-                                                  LatestDecl->getLocation())) &&
-             "The new latest is supposed to come after the previous latest");
-      LatestDecl = cast<RedeclarableTemplateDecl>(NewLatest);
+      if (Decl *NewLatest = Reader.GetDecl(I->second))
+        LatestDecl = cast<RedeclarableTemplateDecl>(NewLatest);
     }
 
     assert(LatestDecl->getKind() == D->getKind() && "Latest kind mismatch");
@@ -1217,8 +1211,8 @@ void ASTDeclReader::VisitClassTemplatePartialSpecializationDecl(
   }
 }
 
-void ASTDeclReader::VisitClassScopeFunctionSpecializationDecl(

-                                    ClassScopeFunctionSpecializationDecl *D) {

+void ASTDeclReader::VisitClassScopeFunctionSpecializationDecl(
+                                    ClassScopeFunctionSpecializationDecl *D) {
   VisitDecl(D);
   D->Specialization = ReadDeclAs<CXXMethodDecl>(Record, Idx);
 }
diff --git a/test/PCH/chain-friend-instantiation.cpp b/test/PCH/chain-friend-instantiation.cpp
new file mode 100644
index 0000000000..294d979112
--- /dev/null
+++ b/test/PCH/chain-friend-instantiation.cpp
@@ -0,0 +1,61 @@
+// RUN: %clang_cc1 %s -ast-print -o - -chain-include %s -chain-include %s
+
+#if !defined(PASS1)
+#define PASS1
+
+template <class T> class TClass;
+
+namespace NS {
+    template <class X, class Y> TClass<X> problematic(X * ptr, const TClass<Y> &src);
+
+    template <class T>
+    class TBaseClass
+    {
+    protected:
+        template <class X, class Y> friend TClass<X> problematic(X * ptr, const TClass<Y> &src);
+    };
+}
+
+template <class T>
+class TClass: public NS::TBaseClass<T>
+{
+public:
+    inline TClass() { }
+};
+
+
+namespace NS {
+    template <class X, class T>
+    TClass<X> problematic(X *ptr, const TClass<T> &src);
+}
+
+template <class X, class T>
+TClass<X> unconst(const TClass<T> &src);
+
+#elif !defined(PASS2)
+#define PASS2
+
+namespace std {
+class s {};
+}
+
+
+typedef TClass<std::s> TStr;
+
+struct crash {
+  TStr str;
+
+  crash(const TClass<std::s> p)
+  {
+    unconst<TStr>(p);
+  }
+};
+
+#else
+
+void f() {
+    const TStr p;
+    crash c(p);
+}
+
+#endif