Fix PR c++/70204 (ICE in non_const_var_error)

gcc/cp/ChangeLog:

	PR c++/70204
	* constexpr.c (non_const_var_error): Check
	DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P.

gcc/testsuite/ChangeLog:

	PR c++/70204
	* g++.dg/cpp0x/constexpr-70204a.C: New test.
	* g++.dg/cpp0x/constexpr-70204b.C: New test.

From-SVN: r234390

gcc/cp/ChangeLog

+2016-03-22  Patrick Palka  <ppalka@gcc.gnu.org>
+
+	PR c++/70204
+	* constexpr.c (non_const_var_error): Check
+	DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P.
+
 2016-03-21  Richard Henderson  <rth@redhat.com>
 
 	PR c++/70273

gcc/cp/constexpr.c

@@ -2763,7 +2763,8 @@ non_const_var_error (tree r)
 	inform (DECL_SOURCE_LOCATION (r),
 		"%q#D is volatile", r);
       else if (!DECL_INITIAL (r)
-	       || !TREE_CONSTANT (DECL_INITIAL (r)))
+	       || !TREE_CONSTANT (DECL_INITIAL (r))
+	       || !DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r))
 	inform (DECL_SOURCE_LOCATION (r),
 		"%qD was not initialized with a constant "
 		"expression", r);

gcc/testsuite/ChangeLog

+2016-03-22  Patrick Palka  <ppalka@gcc.gnu.org>
+
+	PR c++/70204
+	* g++.dg/cpp0x/constexpr-70204a.C: New test.
+	* g++.dg/cpp0x/constexpr-70204b.C: New test.
+
 2016-03-21  Jakub Jelinek  <jakub@redhat.com>
 
 	PR middle-end/70326

gcc/testsuite/g++.dg/cpp0x/constexpr-70204a.C

+// PR c++/70204
+// { dg-do compile { target c++11 } }
+
+int a;
+
+template < int N, int I >
+void fn1 ()
+{
+  const int x = I * a, y = x;
+  fn1 < y, I > (); // { dg-error "constant|no match" }
+}
+
+int
+main ()
+{
+  fn1 < 0, 0 > ();
+  return 0;
+}

gcc/testsuite/g++.dg/cpp0x/constexpr-70204b.C

+// PR c++/70204
+// { dg-do compile { target c++11 } }
+
+int a;
+
+void fn1 ()
+{
+  const int x = 0 * a;
+  constexpr int y = x; // { dg-error "constant" }
+}