From a5dccd4614b84381f6799ae0162cd0859de0fc86 Mon Sep 17 00:00:00 2001
From: Nathan Sidwell <nathan@acm.org>
Date: Mon, 5 Mar 2018 16:12:07 +0000
Subject: [PATCH] [PR c++/84694] ICE on template friend decl

https://gcc.gnu.org/ml/gcc-patches/2018-03/msg00221.html
	PR c++/84694
	* friend.c (do_friend): Restore check for identifier_p inside
	TEMPLATE_ID_EXPR.

	PR c++/84694
	* g++.dg/template/pr84694.C: New.

From-SVN: r258254
---
 gcc/cp/ChangeLog                        | 6 ++++++
 gcc/cp/friend.c                         | 3 ++-
 gcc/testsuite/ChangeLog                 | 5 +++++
 gcc/testsuite/g++.dg/template/pr84694.C | 6 ++++++
 4 files changed, 19 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/g++.dg/template/pr84694.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 5e166350e40..6c37dc3eabb 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2018-03-05  Nathan Sidwell  <nathan@acm.org>
+
+	PR c++/84694
+	* friend.c (do_friend): Restore check for identifier_p inside
+	TEMPLATE_ID_EXPR.
+
 2018-03-05  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	PR c++/84618
diff --git a/gcc/cp/friend.c b/gcc/cp/friend.c
index 8125f1c34d2..b31d4cfb72c 100644
--- a/gcc/cp/friend.c
+++ b/gcc/cp/friend.c
@@ -495,7 +495,8 @@ do_friend (tree ctype, tree declarator, tree decl,
   if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
     {
       declarator = TREE_OPERAND (declarator, 0);
-      declarator = OVL_NAME (declarator);
+      if (!identifier_p (declarator))
+	declarator = OVL_NAME (declarator);
     }
 
   if (ctype)
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 6195e215a9e..934339d97f7 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2018-03-05  Nathan Sidwell  <nathan@acm.org>
+
+	PR c++/84694
+	* g++.dg/template/pr84694.C: New.
+
 2018-03-05  Jakub Jelinek  <jakub@redhat.com>
 
 	PR target/84524
diff --git a/gcc/testsuite/g++.dg/template/pr84694.C b/gcc/testsuite/g++.dg/template/pr84694.C
new file mode 100644
index 00000000000..ba74560c14d
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/pr84694.C
@@ -0,0 +1,6 @@
+// PR c++84694 ICE on friend decl
+template<typename>
+struct a {
+  template<int ()> void b();
+  friend void b<0>(); // ICEd with useless friend decl
+};
-- 
2.30.2