re PR c++/79896 (ICE in gimplify_expr, at gimplify.c:11950 on non-int128 target)

	PR c++/79896
	* decl.c (finish_enum_value_list): If value is error_mark_node,
	don't copy it and change its type.
	* init.c (constant_value_1): Return error_mark_node if DECL_INITIAL
	of CONST_DECL is error_mark_node.

	* g++.dg/ext/int128-5.C: New test.

From-SVN: r246034

gcc/cp/ChangeLog

+2017-03-10  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/79896
+	* decl.c (finish_enum_value_list): If value is error_mark_node,
+	don't copy it and change its type.
+	* init.c (constant_value_1): Return error_mark_node if DECL_INITIAL
+	of CONST_DECL is error_mark_node.
+
 2017-03-09  Marek Polacek  <polacek@redhat.com>
 
 	PR c++/79900 - ICE in strip_typedefs

gcc/cp/decl.c

@@ -14323,9 +14323,12 @@ finish_enum_value_list (tree enumtype)
       input_location = saved_location;
 
       /* Do not clobber shared ints.  */
+      if (value != error_mark_node)
+	{
 	  value = copy_node (value);
 
 	  TREE_TYPE (value) = enumtype;
+	}
       DECL_INITIAL (decl) = value;
     }
 

gcc/cp/init.c

@@ -2162,7 +2162,8 @@ constant_value_1 (tree decl, bool strict_p, bool return_aggregate_cst_ok_p)
       init = DECL_INITIAL (decl);
       if (init == error_mark_node)
 	{
-	  if (DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))
+	  if (TREE_CODE (decl) == CONST_DECL
+	      || DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))
 	    /* Treat the error as a constant to avoid cascading errors on
 	       excessively recursive template instantiation (c++/9335).  */
 	    return init;

gcc/testsuite/ChangeLog

+2017-03-10  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/79896
+	* g++.dg/ext/int128-5.C: New test.
+
 2017-03-10  Segher Boessenkool  <segher@kernel.crashing.org>
 
 	PR testsuite/79356

gcc/testsuite/g++.dg/ext/int128-5.C

+// PR c++/79896
+// { dg-do compile { target { ilp32 && { ! int128 } } } }
+// { dg-options "" }
+
+enum E
+{
+  e1 = 0xffffffffffffffffULL,
+  e2,			// { dg-error "overflow in enumeration values" }
+  e3
+} e = e3;