From a7ddca92d62bca781fd6825829f76e12b0b66096 Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Mon, 22 Apr 2013 14:49:01 -0400
Subject: [PATCH] * mangle.c (write_type): Mangle decltype(auto).

From-SVN: r198150
---
 gcc/cp/ChangeLog                          |  4 ++++
 gcc/cp/mangle.c                           |  5 ++++-
 gcc/testsuite/g++.dg/cpp1y/auto-mangle1.C | 12 ++++++++++++
 3 files changed, 20 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/g++.dg/cpp1y/auto-mangle1.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 7e224ae2e0e..b4680c276eb 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,7 @@
+2013-04-22  Jason Merrill  <jason@redhat.com>
+
+	* mangle.c (write_type): Mangle decltype(auto).
+
 2013-04-19  Jason Merrill  <jason@redhat.com>
 
 	N3638 changes to return type deduction
diff --git a/gcc/cp/mangle.c b/gcc/cp/mangle.c
index 83c3e628da0..8da62b5e969 100644
--- a/gcc/cp/mangle.c
+++ b/gcc/cp/mangle.c
@@ -2019,7 +2019,10 @@ write_type (tree type)
 	    case TEMPLATE_TYPE_PARM:
 	      if (is_auto (type))
 		{
-		  write_identifier ("Da");
+		  if (AUTO_IS_DECLTYPE (type))
+		    write_identifier ("Dc");
+		  else
+		    write_identifier ("Da");
 		  ++is_builtin_type;
 		  break;
 		}
diff --git a/gcc/testsuite/g++.dg/cpp1y/auto-mangle1.C b/gcc/testsuite/g++.dg/cpp1y/auto-mangle1.C
new file mode 100644
index 00000000000..834cfc3ed86
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1y/auto-mangle1.C
@@ -0,0 +1,12 @@
+// Mangling for decltype(auto)
+// { dg-options "-std=c++1y" }
+
+void f();
+
+// { dg-final { scan-assembler "_Z2g1IiEDcv" } }
+template <class T> decltype(auto) g1() { return &f; }
+template decltype(auto) g1<int>();
+
+// { dg-final { scan-assembler "_Z2g2IiEDav" } }
+template <class T> auto g2() { return &f; }
+template auto g2<int>();
-- 
2.30.2