semantics.c (finish_switch_cond): Handle error cases gracefully.

        * semantics.c (finish_switch_cond): Handle error cases gracefully.
        Detected by g++.law/enum5.C
        * typeck.c (build_modify_expr): Check for errors after resolving
        offsets. Detected by g++.brendan/static1.C
        * decl.c (complete_array_type): Ignore initial_value if it is an
        error. Detected by g++.benjamin/17930.C
        * typeck2.c (process_init_constructor): Return error if one argument
        is in error. Detected by g++.benjamin/13478.C

From-SVN: r25740

gcc/cp/ChangeLog

+1999-03-13  Martin von Lwis  <loewis@informatik.hu-berlin.de>
+
+	* semantics.c (finish_switch_cond): Handle error cases gracefully.
+	Detected by g++.law/enum5.C
+
+	* typeck.c (build_modify_expr): Check for errors after resolving
+	offsets. Detected by g++.brendan/static1.C
+
+	* decl.c (complete_array_type): Ignore initial_value if it is an
+	error. Detected by g++.benjamin/17930.C	
+
+	* typeck2.c (process_init_constructor): Return error if one argument
+	is in error. Detected by g++.benjamin/13478.C
+
 1999-03-12  Martin von Lwis  <loewis@informatik.hu-berlin.de>
 
 	* decl.c (select_decl): Allow class templates when we need types.

gcc/cp/decl.c

@@ -8259,6 +8259,8 @@ complete_array_type (type, initial_value, do_default)
 	  /* Make an error message unless that happened already.  */
 	  if (initial_value != error_mark_node)
 	    value = 1;
+	  else
+	    initial_value = NULL_TREE;
 
 	  /* Prevent further error messages.  */
 	  maxindex = build_int_2 (0, 0);

gcc/cp/semantics.c

@@ -490,12 +490,20 @@ finish_switch_cond (cond)
       r = build_min_nt (SWITCH_STMT, cond, NULL_TREE);
       add_tree (r);
     }
-  else
+  else if (cond != error_mark_node)
     {
       emit_line_note (input_filename, lineno);
       c_expand_start_case (cond);
       r = NULL_TREE;
     }
+  else
+    {
+      /* The code is in error, but we don't want expand_end_case to
+         crash. */
+      c_expand_start_case (boolean_false_node);
+      r = NULL_TREE;
+    }
+
   push_switch ();
 
   /* Don't let the tree nodes for COND be discarded by

gcc/cp/typeck.c

@@ -5920,6 +5920,9 @@ build_modify_expr (lhs, modifycode, rhs)
       olhstype = lhstype = TREE_TYPE (lhs);
     }
 
+  if (lhs == error_mark_node)
+    return lhs;
+
   if (TREE_CODE (lhstype) == REFERENCE_TYPE
       && modifycode != INIT_EXPR)
     {

gcc/cp/typeck2.c

@@ -932,6 +932,8 @@ process_init_constructor (type, init, elts)
 		  tree tail1 = tail;
 		  next1 = digest_init (TREE_TYPE (type),
 				       TREE_VALUE (tail), &tail1);
+		  if (next1 == error_mark_node)
+		    return next1;
 		  my_friendly_assert
 		    (same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (type)),
 				  TYPE_MAIN_VARIANT (TREE_TYPE (next1))),