variable.c: fix private constant message

* variable.c (rb_const_search): raise with the actual class/module
  name which defines the private constant.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@56117 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,8 @@
+Fri Sep  9 10:07:40 2016  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* variable.c (rb_const_search): raise with the actual class/module
+	  name which defines the private constant.
+
 Thu Sep  8 17:47:18 2016  Kazuki Tsujimoto  <kazuki@callcc.net>
 
 	* array.c (flatten): use rb_obj_class instead of rb_class_of

test/ruby/test_module.rb

@@ -1360,6 +1360,9 @@ class TestModule < Test::Unit::TestCase
     c.const_set(:FOO, "foo")
     $VERBOSE = verbose
     assert_raise(NameError) { c::FOO }
+    assert_raise_with_message(NameError, /#{c}::FOO/) do
+      Class.new(c)::FOO
+    end
   end
 
   def test_private_constant2

variable.c

@@ -2261,7 +2261,7 @@ rb_const_search(VALUE klass, ID id, int exclude, int recurse, int visibility)
 	while ((ce = rb_const_lookup(tmp, id))) {
 	    if (visibility && RB_CONST_PRIVATE_P(ce)) {
 		rb_name_err_raise("private constant %2$s::%1$s referenced",
-				  klass, ID2SYM(id));
+				  tmp, ID2SYM(id));
 	    }
 	    rb_const_warn_if_deprecated(ce, klass, id);
 	    value = ce->value;