From 8e519a8b0a3543210d7103042cc0a2e1b3603832 Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Sat, 16 Mar 2013 22:38:35 -0400
Subject: [PATCH] re PR c++/56039 (ICE in iterative_hash_template_arg, at
 cp/pt.c:1606)

	PR c++/56039
	* tree.c (strip_typedefs_expr): Complain about lambda, don't abort.

From-SVN: r196741
---
 gcc/cp/ChangeLog                              |  3 +
 gcc/cp/tree.c                                 |  3 +-
 .../g++.dg/cpp0x/lambda/lambda-sfinae1.C      | 55 +++++++++++++++++++
 3 files changed, 60 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/g++.dg/cpp0x/lambda/lambda-sfinae1.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 739795b6a33..983365ca5e8 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,8 @@
 2013-03-16  Jason Merrill  <jason@redhat.com>
 
+	PR c++/56039
+	* tree.c (strip_typedefs_expr): Complain about lambda, don't abort.
+
 	PR c++/54359
 	* parser.c (cp_parser_direct_declarator): Fix late return
 	for out-of-class defn of member function.
diff --git a/gcc/cp/tree.c b/gcc/cp/tree.c
index 6dc33b9493f..42ba677056c 100644
--- a/gcc/cp/tree.c
+++ b/gcc/cp/tree.c
@@ -1421,7 +1421,8 @@ strip_typedefs_expr (tree t)
       }
 
     case LAMBDA_EXPR:
-      gcc_unreachable ();
+      error ("lambda-expression in a constant expression");
+      return error_mark_node;
 
     default:
       break;
diff --git a/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-sfinae1.C b/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-sfinae1.C
new file mode 100644
index 00000000000..973f8a78048
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-sfinae1.C
@@ -0,0 +1,55 @@
+// PR c++/56039
+// { dg-do compile { target c++11 } }
+
+template <bool> struct BoolSink { typedef void type; };
+
+template <typename T, typename U>
+struct AddRvalueReferenceImpl { typedef T type; };
+
+template <typename T>
+struct AddRvalueReferenceImpl<T, typename BoolSink<false &&
+      [] {
+         extern T &&tref;
+      }>::type> {		// { dg-error "lambda" }
+   typedef T &&type;
+};
+
+template <typename T>
+struct AddRvalueReference : AddRvalueReferenceImpl<T, void> { };
+
+namespace ImplHelpers {
+   template <typename T>
+   typename AddRvalueReference<T>::type create(void) { }
+}
+
+template <typename T, typename U, typename ...Args>
+struct IsConstructibleImpl { enum { value = 0 }; };
+
+template <typename T, typename ...Args>
+struct IsConstructibleImpl<T, typename BoolSink<false &&
+      [] {
+         T t( ::ImplHelpers::create<Args>() ...);
+      }>::type, Args ...> {	// { dg-error "lambda" }
+   enum { value = 1 };
+};
+
+template <typename T, typename ...Args>
+struct IsConstructible : IsConstructibleImpl<T, void, Args ...> { };
+
+struct DestroyMe {
+   ~DestroyMe() = delete;
+};
+
+static_assert(+IsConstructible<int>::value, "error");
+static_assert(!IsConstructible<void>::value, "error");
+static_assert(+IsConstructible<int [1]>::value, "error");
+static_assert(!IsConstructible<DestroyMe>::value, "error");
+static_assert(!IsConstructible<int *, char *>::value, "error");
+
+static_assert(+IsConstructible<int &&, int>::value, "error");
+static_assert(!IsConstructible<int &&, int &>::value, "error");
+static_assert(+IsConstructible<int &&, int &&>::value, "error");
+
+// { dg-prune-output "expected" }
+// { dg-prune-output "does not name a class" }
+// { dg-prune-output "static assertion" }
-- 
2.30.2