From 9ee2cecc2fd6a0e4e9633f0a4096b87414635c16 Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Fri, 15 Jul 2016 14:37:56 -0400
Subject: [PATCH] PR c++/71718 - infinite recursion and alias template

	* pt.c (push_tinst_level_loc): Set at_eof before fatal_error.

From-SVN: r238387
---
 gcc/cp/ChangeLog                           |  3 +++
 gcc/cp/pt.c                                |  2 ++
 gcc/testsuite/g++.dg/cpp0x/alias-decl-55.C | 23 ++++++++++++++++++++++
 3 files changed, 28 insertions(+)
 create mode 100644 gcc/testsuite/g++.dg/cpp0x/alias-decl-55.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 81f0a24ec45..1ef3812a82f 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,8 @@
 2016-07-15  Jason Merrill  <jason@redhat.com>
 
+	PR c++/71718
+	* pt.c (push_tinst_level_loc): Set at_eof before fatal_error.
+
 	PR c++/70824
 	* init.c (constant_value_1): Don't instantiated DECL_INITIAL of
 	artificial variables.
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index a1b0ca9a858..73b53e23b4d 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -9132,6 +9132,8 @@ push_tinst_level_loc (tree d, location_t loc)
 
   if (tinst_depth >= max_tinst_depth)
     {
+      /* Tell error.c not to try to instantiate any templates.  */
+      at_eof = 2;
       fatal_error (input_location,
 		   "template instantiation depth exceeds maximum of %d"
                    " (use -ftemplate-depth= to increase the maximum)",
diff --git a/gcc/testsuite/g++.dg/cpp0x/alias-decl-55.C b/gcc/testsuite/g++.dg/cpp0x/alias-decl-55.C
new file mode 100644
index 00000000000..c6d7ae64dd6
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/alias-decl-55.C
@@ -0,0 +1,23 @@
+// PR c++/71718
+// { dg-do compile { target c++11 } }
+
+template <typename T>
+class A : T{};
+
+template <typename T>
+using sp = A<T>;
+
+struct Base {};
+
+template <typename T, int num = 1>
+const sp<T>
+rec() 			// { dg-error "depth" }
+{
+  return rec<T, num - 1>();  
+}
+
+static void f(void) {
+  rec<Base>();
+}
+
+// { dg-prune-output "compilation terminated" }
-- 
2.30.2