class.c (instantiate_type): Be more helpful.

	* class.c (instantiate_type): Be more helpful.
	* decl2.c (import_export_decl): Call import_export_class.
	* cp-tree.h (EMPTY_CONSTRUCTOR_P): Check !TREE_HAS_CONSTRUCTOR.
	* decl2.c (build_expr_from_tree): Propagate TREE_HAS_CONSTRUCTOR.
	* pt.c (tsubst_copy): Likewise.

From-SVN: r23511

gcc/cp/ChangeLog

+1998-11-02  Jason Merrill  <jason@yorick.cygnus.com>
+
+	* class.c (instantiate_type): Be more helpful.
+
+	* decl2.c (import_export_decl): Call import_export_class.
+
+	* cp-tree.h (EMPTY_CONSTRUCTOR_P): Check !TREE_HAS_CONSTRUCTOR.
+	* decl2.c (build_expr_from_tree): Propagate TREE_HAS_CONSTRUCTOR.
+	* pt.c (tsubst_copy): Likewise.
+
 1998-11-02  Mark Mitchell  <mark@markmitchell.com>
 
 	* init.c (expand_vec_init): Fix off-by-one error.

gcc/cp/class.c

@@ -5040,8 +5040,16 @@ instantiate_type (lhstype, rhs, complain)
 	    my_friendly_assert (TREE_CODE (function) == FUNCTION_DECL, 185);
 
 	    if (! DECL_STATIC_FUNCTION_P (function))
-	      cp_error ("reference to `%D' can only be used in a call",
-			function);
+	      {
+		tree t = TREE_TYPE (TREE_OPERAND (rhs, 0));
+		if (TYPE_MAIN_VARIANT (t) == current_class_type)
+		  t = constructor_name (t);
+
+		cp_error ("object-dependent reference to `%D' can only be used in a call",
+			  function);
+		cp_error ("  to form a pointer to member function, say `&%T::%D'",
+			  t, DECL_NAME (function));
+	      }
 
 	    mark_used (function);
 	    return function;

gcc/cp/cp-tree.h

@@ -1482,8 +1482,9 @@ extern int flag_new_for_scope;
    has been duly initialized in its constructor.  */
 #define TREE_HAS_CONSTRUCTOR(NODE) (TREE_LANG_FLAG_4(NODE))
 
-#define EMPTY_CONSTRUCTOR_P(NODE) (TREE_CODE (NODE) == CONSTRUCTOR \
-				   && CONSTRUCTOR_ELTS (NODE) == NULL_TREE)
+#define EMPTY_CONSTRUCTOR_P(NODE) (TREE_CODE (NODE) == CONSTRUCTOR	   \
+				   && CONSTRUCTOR_ELTS (NODE) == NULL_TREE \
+				   && ! TREE_HAS_CONSTRUCTOR (NODE))
 
 #if 0
 /* Indicates that a NON_LVALUE_EXPR came from a C++ reference.

gcc/cp/decl2.c

@@ -2785,6 +2785,7 @@ import_export_decl (decl)
   else if (DECL_FUNCTION_MEMBER_P (decl))
     {
       tree ctype = DECL_CLASS_CONTEXT (decl);
+      import_export_class (ctype);
       if (CLASSTYPE_INTERFACE_KNOWN (ctype)
 	  && (! DECL_ARTIFICIAL (decl) || DECL_VINDEX (decl)))
 	{
@@ -2803,6 +2804,10 @@ import_export_decl (decl)
   else if (DECL_ARTIFICIAL (decl) && DECL_MUTABLE_P (decl))
     {
       tree ctype = TREE_TYPE (DECL_NAME (decl));
+
+      if (IS_AGGR_TYPE (ctype))
+	import_export_class (ctype);
+
       if (IS_AGGR_TYPE (ctype) && CLASSTYPE_INTERFACE_KNOWN (ctype)
 	  && TYPE_VIRTUAL_P (ctype)
 	  /* If the type is a cv-qualified variant of a type, then we
@@ -3852,6 +3857,7 @@ build_expr_from_tree (t)
 
 	r = build_nt (CONSTRUCTOR, NULL_TREE,
 		      build_expr_from_tree (CONSTRUCTOR_ELTS (t)));
+	TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
 
 	if (TREE_TYPE (t))
 	  return digest_init (TREE_TYPE (t), r, 0);

gcc/cp/pt.c

@@ -5917,6 +5917,7 @@ tsubst_copy (t, args, in_decl)
      tree in_decl;
 {
   enum tree_code code;
+  tree r;
 
   if (t == NULL_TREE || t == error_mark_node)
     return t;
@@ -6000,7 +6001,7 @@ tsubst_copy (t, args, in_decl)
 
 	if (id != TREE_OPERAND (t, 0))
 	  {
-	    tree r = build_nt (LOOKUP_EXPR, id);
+	    r = build_nt (LOOKUP_EXPR, id);
 	    LOOKUP_EXPR_GLOBAL (r) = LOOKUP_EXPR_GLOBAL (t);
 	    t = r;
 	  }
@@ -6119,7 +6120,7 @@ tsubst_copy (t, args, in_decl)
     case COND_EXPR:
     case MODOP_EXPR:
       {
-	tree r = build_nt
+	r = build_nt
 	  (code, tsubst_copy (TREE_OPERAND (t, 0), args, in_decl),
 	   tsubst_copy (TREE_OPERAND (t, 1), args, in_decl),
 	   tsubst_copy (TREE_OPERAND (t, 2), args, in_decl));
@@ -6142,7 +6143,7 @@ tsubst_copy (t, args, in_decl)
 
     case NEW_EXPR:
       {
-	tree r = build_nt
+	r = build_nt
 	(code, tsubst_copy (TREE_OPERAND (t, 0), args, in_decl),
 	 tsubst_copy (TREE_OPERAND (t, 1), args, in_decl),
 	 tsubst_copy (TREE_OPERAND (t, 2), args, in_decl));
@@ -6152,7 +6153,7 @@ tsubst_copy (t, args, in_decl)
 
     case DELETE_EXPR:
       {
-	tree r = build_nt
+	r = build_nt
 	(code, tsubst_copy (TREE_OPERAND (t, 0), args, in_decl),
 	 tsubst_copy (TREE_OPERAND (t, 1), args, in_decl));
 	DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
@@ -6223,9 +6224,13 @@ tsubst_copy (t, args, in_decl)
 	return t;
 
     case CONSTRUCTOR:
-      return build
-	(CONSTRUCTOR, tsubst (TREE_TYPE (t), args, in_decl), NULL_TREE,
-	 tsubst_copy (CONSTRUCTOR_ELTS (t), args, in_decl));
+      {
+	r = build
+	  (CONSTRUCTOR, tsubst (TREE_TYPE (t), args, in_decl), NULL_TREE,
+	   tsubst_copy (CONSTRUCTOR_ELTS (t), args, in_decl));
+	TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
+	return r;
+      }
 
     default:
       return t;