vm_insnhelper.c: preserve encoding

* vm_insnhelper.c (vm_getivar): preserve variable name encoding in
  warning message.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@48047 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

2 files changed, 6 insertions, 1 deletions

diff --git a/test/ruby/test_module.rb b/test/ruby/test_module.rb
index f025c1948e..5a0d819fb7 100644
--- a/test/ruby/test_module.rb
+++ b/test/ruby/test_module.rb
@@ -1826,6 +1826,11 @@ class TestModule < Test::Unit::TestCase
     assert_warning '' do
       assert_equal(42, a.ivar)
     end
+
+    name = "@\u{5909 6570}"
+    assert_warning(/instance variable #{name} not initialized/) do
+      assert_nil(a.instance_eval(name))
+    end
   end
 
   def test_uninitialized_attr
diff --git a/vm_insnhelper.c b/vm_insnhelper.c
index b81001b0ef..495b7224fd 100644
--- a/vm_insnhelper.c
+++ b/vm_insnhelper.c
@@ -527,7 +527,7 @@ vm_getivar(VALUE obj, ID id, IC ic, rb_call_info_t *ci, int is_attr)
 
 	if (UNLIKELY(val == Qundef)) {
 	    if (!is_attr && RTEST(ruby_verbose))
-		rb_warning("instance variable %s not initialized", rb_id2name(id));
+		rb_warning("instance variable %"PRIsVALUE" not initialized", QUOTE_ID(id));
 	    val = Qnil;
 	}
 	return val;