From 5d52e47ed6a4f920723ebec371594a3fe7878d7c Mon Sep 17 00:00:00 2001
From: Douglas Gregor <dgregor@apple.com>
Date: Sat, 16 Jan 2010 18:09:52 +0000
Subject: [PATCH] Partial fix for PR6022, where we were complaining when a
 friend function template declared within a class template did not match a
 function in another scope. We really need to rework how friends-in-templates
 are semantically checked.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@93642 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Sema/SemaDecl.cpp                 |  3 ++-
 test/SemaTemplate/friend-template.cpp | 18 +++++++++++++++++-
 2 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index b308613a46..101cae84be 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -3362,7 +3362,8 @@ Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC,
       Diag(NewFD->getLocation(), diag::err_out_of_line_declaration)
         << D.getCXXScopeSpec().getRange();
       NewFD->setInvalidDecl();
-    } else if (!Redeclaration) {
+    } else if (!Redeclaration && 
+               !(isFriend && CurContext->isDependentContext())) {
       // The user tried to provide an out-of-line definition for a
       // function that is a member of a class or namespace, but there
       // was no such member function declared (C++ [class.mfct]p2,
diff --git a/test/SemaTemplate/friend-template.cpp b/test/SemaTemplate/friend-template.cpp
index 05289b10d2..8bc2631e11 100644
--- a/test/SemaTemplate/friend-template.cpp
+++ b/test/SemaTemplate/friend-template.cpp
@@ -1,5 +1,4 @@
 // RUN: %clang_cc1 -fsyntax-only -verify %s
-
 // PR5057
 namespace test0 {
   namespace std {
@@ -107,3 +106,20 @@ namespace test5 {
     template <typename T> friend struct cache;
   };
 }
+
+// PR6022
+namespace PR6022 {
+  template <class T1, class T2 , class T3  > class A;
+
+  namespace inner {
+    template<class T1, class T2, class T3, class T> 
+    A<T1, T2, T3>& f0(A<T1, T2, T3>&, T);
+  } 
+
+  template<class T1, class T2, class T3>
+  class A {
+    template<class U1, class U2, class U3, class T>  
+    friend A<U1, U2, U3>& inner::f0(A<U1, U2, U3>&, T);
+  };
+}
+