(output_pending_init_elements): Don't crash if

constructor_unfilled_fields is 0.

(build_c_cast): When making union constructor,
copy TREE_CONSTANT from the given value.
(initializer_constant_valid_p): Special handling for "constant"
union constructor.

From-SVN: r5921

diff --git a/gcc/c-typeck.c b/gcc/c-typeck.c
index da34eee6195cc84638cac66b30754a54ffa03fc4..11ed850db47970e0469a28a7e957d633def49fbb 100644 (file)
--- a/gcc/c-typeck.c
+++ b/gcc/c-typeck.c
@@ -3469,7 +3469,7 @@ build_c_cast (type, expr)
       if (field)
        {
          char *name;
-         tree nvalue;
+         tree t;
 
          if (pedantic)
            pedwarn ("ANSI C forbids casts to union type");
@@ -3482,9 +3482,11 @@ build_c_cast (type, expr)
            }
          else
            name = "";
-         return digest_init (type, build (CONSTRUCTOR, type, NULL_TREE,
-                                          build_tree_list (field, value)),
-                             0, 0);
+         t = digest_init (type, build (CONSTRUCTOR, type, NULL_TREE,
+                                       build_tree_list (field, value)),
+                          0, 0);
+         TREE_CONSTANT (t) = TREE_CONSTANT (value);
+         return t;
        }
       error ("cast to union type from type not present in union");
       return error_mark_node;
@@ -4033,6 +4035,10 @@ initializer_constant_valid_p (value, endtype)
   switch (TREE_CODE (value))
     {
     case CONSTRUCTOR:
+      if (TREE_CODE (TREE_TYPE (value)) == UNION_TYPE
+         && TREE_CONSTANT (value))
+       return initializer_constant_valid_p (TREE_VALUE (CONSTRUCTOR_ELTS (value)));
+       
       return TREE_STATIC (value) ? null_pointer_node : 0;
 
     case INTEGER_CST:
@@ -5688,8 +5694,9 @@ output_pending_init_elements (all)
                                   0);
              goto retry;
            }
-         else if (tree_int_cst_lt (DECL_FIELD_BITPOS (TREE_PURPOSE (tail)),
-                                   DECL_FIELD_BITPOS (constructor_unfilled_fields)))
+         else if (constructor_unfilled_fields == 0
+                  || tree_int_cst_lt (DECL_FIELD_BITPOS (TREE_PURPOSE (tail)),
+                                      DECL_FIELD_BITPOS (constructor_unfilled_fields)))
            ;
          else if (next == 0
                   || tree_int_cst_lt (DECL_FIELD_BITPOS (TREE_PURPOSE (tail)),