C++ PATCH for c++/57222 (bogus error with alias-template)

[Jason Merrill]

lookup_template_class wasn't dealing properly with getting a 
TEMPLATE_DECL that represents a template template parameter.

Tested x86_64-pc-linux-gnu, applying to trunk and 4.8.
commit 7eed04dd8adeea6654e9275666586e52aef0b629
Author: Jason Merrill <ja...@redhat.com>
Date:   Thu May 9 09:37:53 2013 -0400
    	PR c++/57222
    	* pt.c (lookup_template_class_1): Handle getting a template
    	template parameter as D1.

diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 2cb2abd..0747de6 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -7016,7 +7016,7 @@ maybe_get_template_decl_from_type_decl (tree decl)
     ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
 }
 
-/* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
+/* Given an IDENTIFIER_NODE (or type TEMPLATE_DECL) and a chain of
    parameters, find the desired type.
 
    D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
@@ -7097,6 +7097,11 @@ lookup_template_class_1 (tree d1, tree arglist, tree in_decl, tree context,
       d1 = DECL_NAME (templ);
       context = DECL_CONTEXT (templ);
     }
+  else if (DECL_TEMPLATE_TEMPLATE_PARM_P (d1))
+    {
+      templ = d1;
+      d1 = DECL_NAME (templ);
+    }
 
   /* Issue an error message if we didn't find a template.  */
   if (! templ)
diff --git a/gcc/testsuite/g++.dg/cpp0x/alias-decl-34.C b/gcc/testsuite/g++.dg/cpp0x/alias-decl-34.C
new file mode 100644
index 0000000..4306ab7
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/alias-decl-34.C
@@ -0,0 +1,23 @@
+// PR c++/57222
+// { dg-require-effective-target c++11 }
+
+template <template <typename T> class Templ>
+using Bool = Templ<bool>;
+
+template <typename T>
+class Foo {
+private:
+public:
+    template<template<typename U> class Templ>
+    void method(Bool<Templ> boolTempl);
+};
+
+template <typename T>
+template <template <typename U> class Templ>
+void Foo<T>::method(Bool<Templ> boolTempl) {
+}
+
+int main() {
+    Foo<char> foo;
+    return 0;
+}
diff --git a/gcc/testsuite/g++.dg/template/crash84.C b/gcc/testsuite/g++.dg/template/crash84.C
index c42f85c..103e90a 100644
--- a/gcc/testsuite/g++.dg/template/crash84.C
+++ b/gcc/testsuite/g++.dg/template/crash84.C
@@ -5,7 +5,7 @@
 template<typename T> struct a
 {
     template <template <typename> class C, typename X, C<X>* =0>
-    struct b // { dg-error "class C' is not a template|is not a valid type" }
+    struct b
     {
     };
 };
@@ -13,7 +13,8 @@ template<typename T> struct a
 void
 foo ()
 {
-    a<int> v; // { dg-message "required from here" }
+  a<int> a1; // OK
+  a<int>::b<a,int> b1; // { dg-error "template argument" }
 }
 
-
+// { dg-prune-output "invalid type in declaration" }