PR c++/71092 - ICE with array and constexpr.

	* constexpr.c (cxx_eval_call_expression): Fail quietly when cgraph
	threw away DECL_SAVED_TREE.

From-SVN: r238395

gcc/cp/ChangeLog

 2016-07-15  Jason Merrill  <jason@redhat.com>
 
+	PR c++/71092
+	* constexpr.c (cxx_eval_call_expression): Fail quietly when cgraph
+	threw away DECL_SAVED_TREE.
+
 	PR c++/71117
 	Core 2189
 	* call.c (add_template_conv_candidate): Disable if there are

gcc/cp/constexpr.c

@@ -1504,9 +1504,19 @@ cxx_eval_call_expression (const constexpr_ctx *ctx, tree t,
     }
   else
     {
-      if (!result || result == error_mark_node)
+      if (result && result != error_mark_node)
+	/* OK */;
+      else if (!DECL_SAVED_TREE (fun))
+	{
+	  /* When at_eof >= 2, cgraph has started throwing away
+	     DECL_SAVED_TREE, so fail quietly.  FIXME we get here because of
+	     late code generation for VEC_INIT_EXPR, which needs to be
+	     completely reconsidered.  */
+	  gcc_assert (at_eof >= 2 && ctx->quiet);
+	  *non_constant_p = true;
+	}
+      else
 	{
-	  gcc_assert (DECL_SAVED_TREE (fun));
 	  tree body, parms, res;
 
 	  /* Reuse or create a new unshared copy of this function's body.  */

gcc/testsuite/g++.dg/cpp0x/constexpr-array17.C

+// PR c++/71092
+// { dg-do compile { target c++11 } }
+
+template <typename _Default> struct A { using type = _Default; };
+template <typename _Default, template <typename> class>
+using __detected_or = A<_Default>;
+template <typename _Default, template <typename> class _Op>
+using __detected_or_t = typename __detected_or<_Default, _Op>::type;
+template <typename _Tp> struct B { typedef _Tp value_type; };
+struct C {
+  template <typename _Tp> using __pointer = typename _Tp::pointer;
+};
+template <typename _Alloc> struct J : C {
+  using pointer = __detected_or_t<typename _Alloc::value_type *, __pointer>;
+};
+template <typename _T1> void _Construct(_T1 *) { new _T1; }
+struct D {
+  template <typename _ForwardIterator, typename _Size>
+  static _ForwardIterator __uninit_default_n(_ForwardIterator p1, _Size) {
+    _Construct(p1);
+  }
+};
+template <typename _ForwardIterator, typename _Size>
+void __uninitialized_default_n(_ForwardIterator p1, _Size) {
+  D::__uninit_default_n(p1, 0);
+}
+template <typename _ForwardIterator, typename _Size, typename _Tp>
+void __uninitialized_default_n_a(_ForwardIterator p1, _Size, _Tp) {
+  __uninitialized_default_n(p1, 0);
+}
+template <typename> struct __shared_ptr {
+  constexpr __shared_ptr() : _M_ptr(), _M_refcount() {}
+  int _M_ptr;
+  int _M_refcount;
+};
+template <typename _Alloc> struct F {
+  typedef _Alloc _Tp_alloc_type;
+  struct G {
+    typename J<_Tp_alloc_type>::pointer _M_start;
+    G(_Tp_alloc_type);
+  };
+  F(int, _Alloc p2) : _M_impl(p2) {}
+  G _M_impl;
+};
+template <typename _Tp, typename _Alloc = B<_Tp>> struct K : F<_Alloc> {
+  typedef _Alloc allocator_type;
+  K(int, allocator_type p2 = allocator_type()) : F<_Alloc>(0, p2) {
+    __uninitialized_default_n_a(this->_M_impl._M_start, 0, 0);
+  }
+};
+struct H {
+  H();
+  struct I {
+    __shared_ptr<int> trigger[1];
+  };
+  __shared_ptr<int> resetTrigger_;
+  K<I> states_;
+  __shared_ptr<int> triggerManager_;
+};
+__shared_ptr<int> a;
+H::H() : states_(0), triggerManager_(a) {}