c-typeck.c (lookup_field): New function (for chill).

* c-typeck.c (lookup_field): New function (for chill).
(build_component_ref): Call it.

From-SVN: r5330

gcc/c-typeck.c

@@ -1033,48 +1033,15 @@ default_conversion (exp)
   return exp;
 }
 
-/* Make an expression to refer to the COMPONENT field of
-   structure or union value DATUM.  COMPONENT is an IDENTIFIER_NODE.  */
+/* Look up component name in the structure type definition.  */
      
-tree
-build_component_ref (datum, component)
-     tree datum, component;
+static tree
+lookup_field (type, component)
+     tree type, component;
 {
-  register tree type = TREE_TYPE (datum);
-  register enum tree_code code = TREE_CODE (type);
-  register tree field = NULL;
-  register tree ref;
-
-  /* If DATUM is a COMPOUND_EXPR or COND_EXPR, move our reference inside it
-     unless we are not to support things not strictly ANSI.  */
-  switch (TREE_CODE (datum))
-    {
-    case COMPOUND_EXPR:
-      {
-	tree value = build_component_ref (TREE_OPERAND (datum, 1), component);
-	return build (COMPOUND_EXPR, TREE_TYPE (value),
-		      TREE_OPERAND (datum, 0), value);
-      }
-    case COND_EXPR:
-      return build_conditional_expr
-	(TREE_OPERAND (datum, 0),
-	 build_component_ref (TREE_OPERAND (datum, 1), component),
-	 build_component_ref (TREE_OPERAND (datum, 2), component));
-    }
-
-  /* See if there is a field or component with name COMPONENT.  */
-
-  if (code == RECORD_TYPE || code == UNION_TYPE)
-    {
-      if (TYPE_SIZE (type) == 0)
-	{
-	  incomplete_type_error (NULL_TREE, type);
-	  return error_mark_node;
-	}
-
-      /* Look up component name in the structure type definition.
+  tree field;
 
-	 If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
+  /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
      to the field elements.  Use a binary search on this array to quickly
      find the element.  Otherwise, do a linear search.  TYPE_LANG_SPECIFIC
      will always be set for structures which have many elements.  */
@@ -1093,6 +1060,27 @@ build_component_ref (datum, component)
 
 	  half = (top - bot + 1) >> 1;
 	  field = field_array[bot+half];
+
+	  if (DECL_NAME (field) == NULL_TREE)
+	    {
+	      /* Step through all anon unions in linear fashion.  */
+	      while (DECL_NAME (field_array[bot]) == NULL_TREE)
+		{
+		  tree anon;
+		  field = field_array[bot++];
+		  anon = lookup_field (TREE_TYPE (field), component);
+		  if (anon != NULL_TREE)
+		    return anon;
+		}
+
+	      /* Entire record is only anon unions.  */
+	      if (bot > top)
+		return NULL_TREE;
+
+	      /* Restart the binary search, with new lower bound.  */
+	      continue;
+	    }
+
 	  cmp = (long)DECL_NAME (field) - (long)component;
 	  if (cmp == 0)
 	    break;
@@ -1111,11 +1099,62 @@ build_component_ref (datum, component)
     {
       for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
 	{
+	  if (DECL_NAME (field) == NULL_TREE)
+	    {
+	      tree anon = lookup_field (TREE_TYPE (field), component);
+	      if (anon != NULL_TREE)
+		return anon;
+	    }
+
 	  if (DECL_NAME (field) == component)
 	    break;
 	}
     }
 
+  return field;
+}
+
+/* Make an expression to refer to the COMPONENT field of
+   structure or union value DATUM.  COMPONENT is an IDENTIFIER_NODE.  */
+
+tree
+build_component_ref (datum, component)
+     tree datum, component;
+{
+  register tree type = TREE_TYPE (datum);
+  register enum tree_code code = TREE_CODE (type);
+  register tree field = NULL;
+  register tree ref;
+
+  /* If DATUM is a COMPOUND_EXPR or COND_EXPR, move our reference inside it
+     unless we are not to support things not strictly ANSI.  */
+  switch (TREE_CODE (datum))
+    {
+    case COMPOUND_EXPR:
+      {
+	tree value = build_component_ref (TREE_OPERAND (datum, 1), component);
+	return build (COMPOUND_EXPR, TREE_TYPE (value),
+		      TREE_OPERAND (datum, 0), value);
+      }
+    case COND_EXPR:
+      return build_conditional_expr
+	(TREE_OPERAND (datum, 0),
+	 build_component_ref (TREE_OPERAND (datum, 1), component),
+	 build_component_ref (TREE_OPERAND (datum, 2), component));
+    }
+
+  /* See if there is a field or component with name COMPONENT.  */
+
+  if (code == RECORD_TYPE || code == UNION_TYPE)
+    {
+      if (TYPE_SIZE (type) == 0)
+	{
+	  incomplete_type_error (NULL_TREE, type);
+	  return error_mark_node;
+	}
+
+      field = lookup_field (type, component);
+
       if (!field)
 	{
 	  error (code == RECORD_TYPE