From 117ad0be08050242d0235b586dc431038f04dcf0 Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Thu, 15 Feb 2018 14:46:13 -0500
Subject: [PATCH] PR c++/84376 - ICE with omitted template arguments.

	* pt.c (dguide_name_p): Check for IDENTIFIER_NODE.

From-SVN: r257706
---
 gcc/cp/ChangeLog                               | 3 +++
 gcc/cp/pt.c                                    | 3 ++-
 gcc/testsuite/g++.dg/cpp1z/class-deduction47.C | 7 +++++++
 3 files changed, 12 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/g++.dg/cpp1z/class-deduction47.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 5ecc8ab2672..58073748315 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,5 +1,8 @@
 2018-02-15  Jason Merrill  <jason@redhat.com>
 
+	PR c++/84376 - ICE with omitted template arguments.
+	* pt.c (dguide_name_p): Check for IDENTIFIER_NODE.
+
 	PR c++/84368 - wrong error with local variable in variadic lambda.
 	* pt.c (tsubst_pack_expansion): Fix handling of non-packs in
 	local_specializations.
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index cd1aed8d677..268cfe5a454 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -25454,7 +25454,8 @@ dguide_name (tree tmpl)
 bool
 dguide_name_p (tree name)
 {
-  return (TREE_TYPE (name)
+  return (TREE_CODE (name) == IDENTIFIER_NODE
+	  && TREE_TYPE (name)
 	  && !strncmp (IDENTIFIER_POINTER (name), dguide_base,
 		       strlen (dguide_base)));
 }
diff --git a/gcc/testsuite/g++.dg/cpp1z/class-deduction47.C b/gcc/testsuite/g++.dg/cpp1z/class-deduction47.C
new file mode 100644
index 00000000000..3e47f58e698
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1z/class-deduction47.C
@@ -0,0 +1,7 @@
+// PR c++/84376
+
+template<int> struct A {};
+
+template<typename T> T foo() { return T(); }
+
+template<> A foo<A>();		// { dg-error "A" }
-- 
2.30.2