PR4794: Make instantiating friend class decls not crash.

llvm-svn: 80272
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 045c12a..1e1b6e8 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -4311,7 +4311,10 @@
   New->setLexicalDeclContext(CurContext);
 
   // Set the access specifier.
-  if (!Invalid && TUK != TUK_Friend)
+  // FIXME: This used to be skipped for friend tag decls, but it led to an
+  // assertion in Decl::CheckAccessDeclContext(); once various issues with
+  // friend class decls are sorted out, this should be revisited.
+  if (!Invalid)
     SetMemberAccessSpecifier(New, PrevDecl, AS);
 
   if (TUK == TUK_Definition)
diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 42fc1f8..a79742b 100644
--- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -265,6 +265,8 @@
   FriendClassDecl *NewD =
     FriendClassDecl::Create(SemaRef.Context, DC, D->getLocation(), T,
                             D->getFriendLoc());
+  NewD->setLexicalDeclContext(Owner);
+
   Owner->addDecl(NewD);
   return NewD;
 }
diff --git a/clang/test/SemaTemplate/instantiate-friend-class.cpp b/clang/test/SemaTemplate/instantiate-friend-class.cpp
new file mode 100644
index 0000000..004bf1b
--- /dev/null
+++ b/clang/test/SemaTemplate/instantiate-friend-class.cpp
@@ -0,0 +1,8 @@
+// RUN: clang-cc -fsyntax-only -verify %s
+
+template <class T> class X
+{
+  friend class Y;
+};
+X<int> y;
+