From 0c0d447a96c1786e855782bd18f35f307e5ca2d8 Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Sat, 25 Jul 2015 02:54:57 -0400
Subject: [PATCH] re PR c++/64989 (constant-initialization of self-referencing
 array)

	PR c++/64989
	* pt.c (splice_late_return_type): Correct deduced return type for
	abbreviated function template.

From-SVN: r226207
---
 gcc/cp/ChangeLog                     |  6 ++++++
 gcc/cp/pt.c                          | 20 ++++++++++++--------
 gcc/testsuite/g++.dg/cpp1z/abbrev1.C | 11 +++++++++++
 3 files changed, 29 insertions(+), 8 deletions(-)
 create mode 100644 gcc/testsuite/g++.dg/cpp1z/abbrev1.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index df805e678af..39869df547c 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2015-07-24  Jason Merrill  <jason@redhat.com>
+
+	PR c++/64989
+	* pt.c (splice_late_return_type): Correct deduced return type for
+	abbreviated function template.
+
 2015-07-24  Richard Biener  <rguenther@suse.de>
 
 	* init.c (build_vec_init): Build iterator bound in the same
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 5004883a63e..971c98ee0d9 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -22459,15 +22459,19 @@ do_auto_deduction (tree type, tree init, tree auto_node)
 tree
 splice_late_return_type (tree type, tree late_return_type)
 {
-  tree argvec;
+  if (is_auto (type))
+    {
+      if (late_return_type)
+	return late_return_type;
 
-  if (late_return_type == NULL_TREE)
-    return type;
-  argvec = make_tree_vec (1);
-  TREE_VEC_ELT (argvec, 0) = late_return_type;
-  if (current_template_parms)
-    argvec = add_to_template_args (current_template_args (), argvec);
-  return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
+      tree idx = get_template_parm_index (type);
+      if (TEMPLATE_PARM_LEVEL (idx) <= processing_template_decl)
+	/* In an abbreviated function template we didn't know we were dealing
+	   with a function template when we saw the auto return type, so update
+	   it to have the correct level.  */
+	return make_auto_1 (TYPE_IDENTIFIER (type));
+    }
+  return type;
 }
 
 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto' or
diff --git a/gcc/testsuite/g++.dg/cpp1z/abbrev1.C b/gcc/testsuite/g++.dg/cpp1z/abbrev1.C
new file mode 100644
index 00000000000..68a0bf3acad
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1z/abbrev1.C
@@ -0,0 +1,11 @@
+// PR c++/64969
+// { dg-options "-std=c++1z" }
+
+auto f1(auto x) { return *x; }
+decltype(auto) f2(auto x) { return *x; }
+auto f3(auto x) -> int { return *x; }
+
+int i;
+auto r1 = f1(&i);
+auto r2 = f2(&i);
+auto r3 = f3(&i);
-- 
2.30.2