4 files changed, 68 insertions, 9 deletions
diff --git a/clang/lib/Sema/SemaAccess.cpp b/clang/lib/Sema/SemaAccess.cpp
index 90d31772221..e2b7a7e061d 100644
--- a/clang/lib/Sema/SemaAccess.cpp
+++ b/clang/lib/Sema/SemaAccess.cpp
@@ -514,6 +514,9 @@ static AccessResult MatchesFriend(Sema &S,
 static AccessResult MatchesFriend(Sema &S,
                                   const EffectiveContext &EC,
                                   FriendDecl *FriendD) {
+  if (FriendD->isInvalidDecl())
+    return AR_accessible;
+
   if (TypeSourceInfo *T = FriendD->getFriendType())
     return MatchesFriend(S, EC, T->getType()->getCanonicalTypeUnqualified());
 
diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index 19580957832..1d633a90480 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -6538,6 +6538,8 @@ Sema::ActOnFriendFunctionDecl(Scope *S,
   FrD->setAccess(AS_public);
   CurContext->addDecl(FrD);
 
+  if (ND->isInvalidDecl()) FrD->setInvalidDecl();
+
   return DeclPtrTy::make(ND);
 }
 
diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index 5cfacf78b57..af852aa3406 100644
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -1365,8 +1365,12 @@ Sema::MatchTemplateParametersToScopeSpecifier(SourceLocation DeclStartLoc,
   // If there were at least as many template-ids as there were template
   // parameter lists, then there are no template parameter lists remaining for
   // the declaration itself.
-  if (Idx >= NumParamLists)
+  if (Idx >= NumParamLists) {
+    // Silently drop template member friend declarations.
+    // TODO: implement these
+    if (IsFriend && NumParamLists) Invalid = true;
     return 0;
+  }
 
   // If there were too many template parameter lists, complain about that now.
   if (Idx != NumParamLists - 1) {
@@ -1395,6 +1399,11 @@ Sema::MatchTemplateParametersToScopeSpecifier(SourceLocation DeclStartLoc,
     }
   }
 
+  // Silently drop template member template friend declarations.
+  // TODO: implement these
+  if (IsFriend && NumParamLists > 1)
+    Invalid = true;
+
   // Return the last template parameter list, which corresponds to the
   // entity being declared.
   return ParamLists[NumParamLists - 1];
diff --git a/clang/test/CXX/temp/temp.decls/temp.friend/p5.cpp b/clang/test/CXX/temp/temp.decls/temp.friend/p5.cpp
index f23611bd505..82c2b3169d4 100644
--- a/clang/test/CXX/temp/temp.decls/temp.friend/p5.cpp
+++ b/clang/test/CXX/temp/temp.decls/temp.friend/p5.cpp
@@ -1,13 +1,58 @@
 // RUN: %clang_cc1 -fsyntax-only -verify %s
 
-template <class T> class A {
-  class Member {
+namespace test0 {
+  template <class T> class A {
+    class Member {};
   };
-};
 
-class B {
-  template <class T> friend class A<T>::Member;
-};
+  class B {
+    template <class T> friend class A<T>::Member;
+  };
+
+  A<int> a;
+  B b;
+}
+
+// rdar://problem/8204127
+namespace test1 {
+  template <class T> struct A;
+
+  class C {
+    static void foo();
+    template <class T> friend void A<T>::f();
+  };
 
-A<int> a;
-B b;
+  template <class T> struct A {
+    void f() { C::foo(); }
+  };
+
+  template <class T> struct A<T*> {
+    void f() { C::foo(); }
+  };
+
+  template <> struct A<char> {
+    void f() { C::foo(); }
+  };
+}
+
+// FIXME: these should fail!
+namespace test2 {
+  template <class T> struct A;
+
+  class C {
+    static void foo();
+    template <class T> friend void A<T>::g();
+  };
+
+  template <class T> struct A {
+    void f() { C::foo(); }
+  };
+
+  template <class T> struct A<T*> {
+    void f() { C::foo(); }
+  };
+
+  template <> struct A<char> {
+    void f() { C::foo(); }
+  };
+}