class.c (check_field_decls): Remove empty_p parameter.

	* class.c (check_field_decls): Remove empty_p parameter.  Instead,
	clear CLASSTYPE_EMPTY_P.
	(build_base_field): Likewise.
	(build_base_fields): Likewise.
	(check_bases_and_members): Likewise.
	(create_vtbl_ptr): Likewise.
	(layout_class_type): Likewise.  Ensure that empty classes have
	size zero when used as base classes in the 3.2 ABI.
	(finish_struct_1): Initialize CLASSTYPE_EMPTY_P and
	CLASSTYPE_NEARLY_EMPTY_P.  Adjust calls to avoid passing empty_p
	parameter.
	(is_empty_class): Correct definition when using post-3.2 ABI.
	* cp-tree.h (lang_type_class): Add empty_p.
	(CLASSTYPE_EMPTY_P): New macro.

From-SVN: r58170

gcc/cp/ChangeLog

+2002-10-14  Mark Mitchell  <mark@codesourcery.com>
+
+	* class.c (check_field_decls): Remove empty_p parameter.  Instead,
+	clear CLASSTYPE_EMPTY_P.
+	(build_base_field): Likewise.
+	(build_base_fields): Likewise.
+	(check_bases_and_members): Likewise.
+	(create_vtbl_ptr): Likewise.
+	(layout_class_type): Likewise.  Ensure that empty classes have
+	size zero when used as base classes in the 3.2 ABI.
+	(finish_struct_1): Initialize CLASSTYPE_EMPTY_P and
+	CLASSTYPE_NEARLY_EMPTY_P.  Adjust calls to avoid passing empty_p
+	parameter.
+	(is_empty_class): Correct definition when using post-3.2 ABI.
+	* cp-tree.h (lang_type_class): Add empty_p.
+	(CLASSTYPE_EMPTY_P): New macro.
+
 2002-10-12  Nathan Sidwell  <nathan@codesourcery.com>
 
 	* init.c (build_delete): Do not apply save_expr for arrays.

gcc/cp/cp-tree.h

@@ -1134,6 +1134,7 @@ struct lang_type_class GTY(())
 
   unsigned anon_aggr : 1;
   unsigned non_zero_init : 1;
+  unsigned empty_p : 1;
 
   /* When adding a flag here, consider whether or not it ought to
      apply to a template instance if it applies to the template.  If
@@ -1142,7 +1143,7 @@ struct lang_type_class GTY(())
   /* There are some bits left to fill out a 32-bit word.  Keep track
      of this by updating the size of this bitfield whenever you add or
      remove a flag.  */
-  unsigned dummy : 6;
+  unsigned dummy : 5;
 
   int vsize;
 
@@ -1447,6 +1448,10 @@ struct lang_type GTY(())
 #define CLASSTYPE_NON_ZERO_INIT_P(NODE) \
   (LANG_TYPE_CLASS_CHECK (NODE)->non_zero_init)
 
+/* Nonzero if this class is "empty" in the sense of the C++ ABI.  */
+#define CLASSTYPE_EMPTY_P(NODE) \
+  (LANG_TYPE_CLASS_CHECK (NODE)->empty_p)
+
 /* Nonzero if this class is "nearly empty", i.e., contains only a
    virtual function table pointer.  */
 #define CLASSTYPE_NEARLY_EMPTY_P(NODE) \

gcc/testsuite/ChangeLog

+2002-10-14  Mark Mitchell  <mark@codesourcery.com>
+
+	* g++.dg/abi/empty8.C: New test.
+
 2002-10-15  Nathan Sidwell  <nathan@codesourcery.com>
 
 	* g++.dg/init/ctor1.C: New test.

gcc/testsuite/g++.dg/abi/empty8.C

+// { dg-do run }
+// { dg-options "-fabi-version=0" }
+
+struct E1 {};
+struct E2 : public E1 {};
+struct S1 { int i; };
+struct S2 : public S1, E2 {};
+
+S2 s2;
+
+int main () {
+  if ((char *)(E2*) &s2 != (char *)&s2)
+    return 1;
+}