2007-11-23  Jakub Jelinek  <jakub@redhat.com>

	PR c++/30293
	PR c++/30294
	* decl.c (cp_finish_decl): Disallow variable or field
	definitions if extern "Java" aggregates.
	(grokparms): Disallow parameters with extern "Java"
	aggregates.
	(check_function_type): Disallow function return values
	with extern "Java" aggregates.
	* init.c (build_new_1): Disallow placement new with
	extern "Java" aggregates.

	* g++.dg/ext/java-2.C: New test.

--- gcc/cp/decl.c.jj	2007-11-19 17:46:41.000000000 +0100
+++ gcc/cp/decl.c	2007-11-22 13:34:52.000000000 +0100
@@ -5349,6 +5349,20 @@ cp_finish_decl (tree decl, tree init, bo
 	     is *not* defined.  */
 	  && (!DECL_EXTERNAL (decl) || init))
 	{
+	  if (TYPE_FOR_JAVA (type) && IS_AGGR_TYPE (type))
+	    {
+	      tree jclass
+		= IDENTIFIER_GLOBAL_VALUE (get_identifier ("jclass"));
+	      /* Allow libjava/prims.cc define primitive classes.  */
+	      if (init != NULL_TREE
+		  || jclass == NULL_TREE
+		  || TREE_CODE (jclass) != TYPE_DECL
+		  || !POINTER_TYPE_P (TREE_TYPE (jclass))
+		  || !same_type_ignoring_top_level_qualifiers_p
+					(type, TREE_TYPE (TREE_TYPE (jclass))))
+		error ("Java object %qD not allocated with %<new%>", decl);
+	      init = NULL_TREE;
+	    }
 	  if (init)
 	    {
 	      DECL_NONTRIVIALLY_INITIALIZED_P (decl) = 1;
@@ -5419,6 +5433,9 @@ cp_finish_decl (tree decl, tree init, bo
       else if (TREE_CODE (type) == ARRAY_TYPE)
 	layout_type (type);
     }
+  else if (TREE_CODE (decl) == FIELD_DECL
+	   && TYPE_FOR_JAVA (type) && IS_AGGR_TYPE (type))
+    error ("non-static data member %qD has Java class type", decl);
 
   /* Add this declaration to the statement-tree.  This needs to happen
      after the call to check_initializer so that the DECL_EXPR for a
@@ -8993,6 +9010,16 @@ grokparms (cp_parameter_declarator *firs
 	  TREE_TYPE (decl) = error_mark_node;
 	}
 
+      if (type != error_mark_node
+	  && TYPE_FOR_JAVA (type)
+	  && IS_AGGR_TYPE (type))
+	{
+	  error ("parameter %qD has Java class type", decl);
+	  type = error_mark_node;
+	  TREE_TYPE (decl) = error_mark_node;
+	  init = NULL_TREE;
+	}
+
       if (type != error_mark_node)
 	{
 	  /* Top-level qualifiers on the parameters are
@@ -10465,11 +10492,15 @@ check_function_type (tree decl, tree cur
 
   if (dependent_type_p (return_type))
     return;
-  if (!COMPLETE_OR_VOID_TYPE_P (return_type))
+  if (!COMPLETE_OR_VOID_TYPE_P (return_type)
+      || (TYPE_FOR_JAVA (return_type) && IS_AGGR_TYPE (return_type)))
     {
       tree args = TYPE_ARG_TYPES (fntype);
-	  
-      error ("return type %q#T is incomplete", return_type);
+
+      if (!COMPLETE_OR_VOID_TYPE_P (return_type))
+	error ("return type %q#T is incomplete", return_type);
+      else
+	error ("return type has Java class type %q#T", return_type);
 
       /* Make it return void instead.  */
       if (TREE_CODE (fntype) == METHOD_TYPE)
--- gcc/cp/init.c.jj	2007-09-20 21:26:48.000000000 +0200
+++ gcc/cp/init.c	2007-11-22 10:49:47.000000000 +0100
@@ -1786,6 +1786,11 @@ build_new_1 (tree placement, tree type, 
 		    (alloc_fn,
 		     build_tree_list (NULL_TREE, class_addr)));
     }
+  else if (TYPE_FOR_JAVA (elt_type))
+    {
+      error ("Java class %q#T object allocated using placement new", elt_type);
+      return error_mark_node;
+    }
   else
     {
       tree fnname;
--- gcc/testsuite/g++.dg/ext/java-2.C.jj	2007-11-22 10:55:10.000000000 +0100
+++ gcc/testsuite/g++.dg/ext/java-2.C	2007-11-22 10:54:59.000000000 +0100
@@ -0,0 +1,79 @@
+// PR c++/30293
+// PR c++/30294
+// { dg-do compile }
+// { dg-options "" }
+
+extern "Java" {
+typedef __java_byte jbyte;
+namespace java {
+namespace lang {
+  class Object {};
+  class Class {};
+}
+}
+typedef struct java::lang::Object* jobject;
+typedef java::lang::Class *jclass;
+}
+extern "C" jobject _Jv_AllocObject (jclass);
+
+extern "Java" {
+  struct A { static java::lang::Class class$; };
+}
+
+struct B {
+  A a;		// { dg-error "has Java class type" }
+};
+
+void* operator new (__SIZE_TYPE__, void*) throw();
+char buf[1024];
+
+A a;		// { dg-error "not allocated with" }
+A b = A ();	// { dg-error "not allocated with" }
+A *c = new ((void *) buf) A ();	// { dg-error "using placement new" }
+A *d = new A ();
+jbyte e = 6;
+
+const A fn1 ()	// { dg-error "return type has Java class type" }
+{
+  A a;		// { dg-error "not allocated with" }
+  return a;
+}
+
+A fn2 ()	// { dg-error "return type has Java class type" }
+{
+  A a;		// { dg-error "not allocated with" }
+  return a;
+}
+
+A *fn3 ()
+{
+  return new A ();
+}
+
+A &fn4 ()
+{
+  return *c;
+}
+
+jbyte fn5 ()
+{
+  return 7;
+}
+
+void fn6 (A x)	// { dg-error "has Java class type" }
+{
+}
+
+void fn7 (const A x)	// { dg-error "has Java class type" }
+{
+}
+
+void fn8 (A *x)
+{
+  (void) x;
+}
+
+void fn9 (jbyte x)
+{
+  (void) x;
+}