From 2c65d990eb80d25c2e040be14a2918a0311dc37c Mon Sep 17 00:00:00 2001
From: Nathan Sidwell <nathan@acm.org>
Date: Wed, 18 Jan 2017 12:51:28 +0000
Subject: [PATCH] re PR c++/79091 (ICE in write_unnamed_type)

	PR c++/79091
	* mangle.c (write_exception_spec): Check nothrow explicitly.
	(write_encoding): Don't increment processing_template_decl around
	encoding.

	PR c++/79091
	* g++.dg/pr79091.C: New.

From-SVN: r244575
---
 gcc/cp/ChangeLog               |  7 +++++++
 gcc/cp/mangle.c                | 14 ++++++--------
 gcc/testsuite/ChangeLog        |  5 +++++
 gcc/testsuite/g++.dg/pr79091.C | 25 +++++++++++++++++++++++++
 4 files changed, 43 insertions(+), 8 deletions(-)
 create mode 100644 gcc/testsuite/g++.dg/pr79091.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index a42454a478a..7733be7cc52 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,10 @@
+2017-01-18  Nathan Sidwell  <nathan@acm.org>
+
+	PR c++/79091
+	* mangle.c (write_exception_spec): Check nothrow explicitly.
+	(write_encoding): Don't increment processing_template_decl around
+	encoding.
+
 2017-01-18  Markus Trippelsdorf  <markus@trippelsdorf.de>
 
 	PR c++/70182
diff --git a/gcc/cp/mangle.c b/gcc/cp/mangle.c
index d1b107cbb1d..033660f0091 100644
--- a/gcc/cp/mangle.c
+++ b/gcc/cp/mangle.c
@@ -366,17 +366,19 @@ write_exception_spec (tree spec)
       return;
     }
 
-  if (nothrow_spec_p (spec))
+  if (spec == noexcept_true_spec || spec == empty_except_spec)
     write_string ("Do");
-  else if (TREE_PURPOSE (spec))
+  else if (tree expr = TREE_PURPOSE (spec))
     {
-      gcc_assert (uses_template_parms (TREE_PURPOSE (spec)));
+      /* noexcept (expr)  */
+      gcc_assert (uses_template_parms (expr));
       write_string ("DO");
-      write_expression (TREE_PURPOSE (spec));
+      write_expression (expr);
       write_char ('E');
     }
   else
     {
+      /* throw (type-list) */
       write_string ("Dw");
       for (tree t = spec; t; t = TREE_CHAIN (t))
 	write_type (TREE_VALUE (t));
@@ -829,7 +831,6 @@ write_encoding (const tree decl)
 
       if (tmpl)
 	{
-	  ++processing_template_decl;
 	  fn_type = get_mostly_instantiated_function_type (decl);
 	  /* FN_TYPE will not have parameter types for in-charge or
 	     VTT parameters.  Therefore, we pass NULL_TREE to
@@ -846,9 +847,6 @@ write_encoding (const tree decl)
       write_bare_function_type (fn_type,
 				mangle_return_type_p (decl),
 				d);
-
-      if (tmpl)
-	--processing_template_decl;
     }
 }
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 738afb621b2..6822d3dcd1e 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2017-01-18  Nathan Sidwell  <nathan@acm.org>
+
+	PR c++/79091
+	* g++.dg/pr79091.C: New.
+
 2017-01-17  Joe Seymour  <joe.s@somniumtech.com>
 
 	* gcc.target/msp430/mul_f5_muldef.c: New test.
diff --git a/gcc/testsuite/g++.dg/pr79091.C b/gcc/testsuite/g++.dg/pr79091.C
new file mode 100644
index 00000000000..ad8cf5a43e5
--- /dev/null
+++ b/gcc/testsuite/g++.dg/pr79091.C
@@ -0,0 +1,25 @@
+// PR 79091 ICE mangling an unnamed enum in a tempate instantiation.
+
+enum  {
+  One = 1
+};
+
+template<int Options>
+class Matrix {};
+
+template<int Dim>
+Matrix<Dim ? One : 0> *Bar ()
+{
+  return 0;
+}
+
+template<int Opt> 
+Matrix<Opt> *Baz ()
+{
+  return 0;
+}
+
+bool Foo ()
+{
+  return Baz<1> () == Bar<1> ();
+}
-- 
2.30.2