class.c, [...]: Remove com_interface attribute support.

        * class.c, cp-tree.h, rtti.c: Remove com_interface attribute support.
        * tree.c (cp_valid_lang_attribute): Warn about use of com_interface
        attribute.

From-SVN: r42465

gcc/cp/ChangeLog

+2001-05-22  Jason Merrill  <jason_merrill@redhat.com>
+
+	* class.c, cp-tree.h, rtti.c: Remove com_interface attribute support.
+	* tree.c (cp_valid_lang_attribute): Warn about use of com_interface
+	attribute.
+
 2001-05-22  Joseph S. Myers  <jsm28@cam.ac.uk>
 
 	* parse.y: Refer to compound literals as such, not as

gcc/cp/class.c

@@ -1690,18 +1690,6 @@ check_bases (t, cant_have_default_ctor_p, cant_have_const_ctor_p,
       TYPE_OVERLOADS_ARRAY_REF (t) |= TYPE_OVERLOADS_ARRAY_REF (basetype);
       TYPE_OVERLOADS_ARROW (t) |= TYPE_OVERLOADS_ARROW (basetype);
       TYPE_POLYMORPHIC_P (t) |= TYPE_POLYMORPHIC_P (basetype);
-
-      /* Derived classes can implicitly become COMified if their bases
-	 are COM.  */
-      if (CLASSTYPE_COM_INTERFACE (basetype))
-	CLASSTYPE_COM_INTERFACE (t) = 1;
-      else if (i == 0 && CLASSTYPE_COM_INTERFACE (t))
-	{
-	  cp_error 
-	    ("COM interface type `%T' with non-COM leftmost base class `%T'",
-	     t, basetype);
-	  CLASSTYPE_COM_INTERFACE (t) = 0;
-	}
     }
 }
 
@@ -7993,10 +7981,6 @@ build_rtti_vtbl_entries (binfo, vid)
   basetype = BINFO_TYPE (binfo);
   t = BINFO_TYPE (vid->rtti_binfo);
 
-  /* For a COM object there is no RTTI entry.  */
-  if (CLASSTYPE_COM_INTERFACE (basetype))
-    return;
-
   /* To find the complete object, we will first convert to our most
      primary base, and then add the offset in the vtbl to that value.  */
   b = binfo;

gcc/cp/cp-tree.h

@@ -132,8 +132,6 @@ Boston, MA 02111-1307, USA.  */
      use a virtual thunk, as opposed to an ordinary thunk.
 
      The BV_FN is the declaration for the virtual function itself.
-     When CLASSTYPE_COM_INTERFACE_P does not hold, the first entry
-     does not have a BV_FN; it is just an offset.
 
      The BV_OVERRIDING_BASE is the binfo for the final overrider for
      this function.  (That binfo's BINFO_TYPE will always be the same
@@ -1578,10 +1576,6 @@ struct lang_type
 #define CLASSTYPE_NEARLY_EMPTY_P(NODE) \
   (TYPE_LANG_SPECIFIC (NODE)->nearly_empty_p)
 
-/* Nonzero means that this type is meant for communication via COM.  */
-#define CLASSTYPE_COM_INTERFACE(NODE) \
-  (TYPE_LANG_SPECIFIC(NODE)->com_interface)
-
 /* A list of class types of which this type is a friend.  The
    TREE_VALUE is normally a TYPE, but will be a TEMPLATE_DECL in the
    case of a template friend.  */

gcc/cp/rtti.c

@@ -122,11 +122,6 @@ build_headof (exp)
 
   if (!TYPE_POLYMORPHIC_P (type))
     return exp;
-  if (CLASSTYPE_COM_INTERFACE (type))
-    {
-      cp_error ("RTTI not supported for COM interface type `%T'", type);
-      return error_mark_node;
-    }
 
   /* If we don't have rtti stuff, get to a sub-object that does.  */
   if (!CLASSTYPE_VFIELDS (TREE_TYPE (TREE_TYPE (exp))))
@@ -222,11 +217,6 @@ get_tinfo_decl_dynamic (exp)
 
       if (! flag_rtti)
 	error ("taking dynamic typeid of object with -fno-rtti");
-      if (CLASSTYPE_COM_INTERFACE (type))
-	{
-	  cp_error ("RTTI not supported for COM interface type `%T'", type);
-	  return error_mark_node;
-	}
 
       /* If we don't have rtti stuff, get to a sub-object that does.  */
       if (! CLASSTYPE_VFIELDS (type))

gcc/cp/tree.c

@@ -2236,12 +2236,7 @@ cp_valid_lang_attribute (attr_name, attr_args, decl, type)
     }
   if (is_attribute_p ("com_interface", attr_name))
     {
-      if (! flag_vtable_thunks)
-	{
-	  error ("`com_interface' only supported with -fvtable-thunks");
-	  return 0;
-	}
-
+      static int warned;
       if (attr_args != NULL_TREE
 	  || decl != NULL_TREE
 	  || ! CLASS_TYPE_P (type)
@@ -2251,6 +2246,9 @@ cp_valid_lang_attribute (attr_name, attr_args, decl, type)
 	  return 0;
 	}
 
+      if (! warned++)
+	warning ("\
+`com_interface' is obsolete; g++ vtables are now COM-compatible by default");
       return 1;
     }
   else if (is_attribute_p ("init_priority", attr_name))

gcc/testsuite/g++.old-deja/g++.ext/comint1.C

-// Test that we can use mixins with COM classes.
-
-struct A
-{
-  virtual int foo () = 0;
-  virtual int bar () = 0;
-} __attribute__((__com_interface__));
-
-struct B
-{
-  virtual int baz () { return 5; }
-};
-
-struct C : public A, public B
-{
-  int foo () { return 0; }
-  int bar () { return 1; }
-};
-
-int main ()
-{
-  C c;
-  return c.foo ();
-}