diff --git a/ChangeLog b/ChangeLog
index 73e1f9e094..9061b20f3a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Sun Aug 11 15:10:40 2013  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* parse.y (rb_enc_symname_type): allow ID_ATTRSET for ID_INSTANCE,
+	  ID_GLOBAL, ID_CLASS, ID_JUNK too.  [Bug #8756]
+
 Sun Aug 11 13:17:00 2013  Charlie Somerville  <charliesome@ruby-lang.org>
 
 	* include/ruby/encoding.h: Reduce ENCODING_INLINE_MAX to 127 as this
diff --git a/parse.y b/parse.y
index f5e79c18e7..060691f7b7 100644
--- a/parse.y
+++ b/parse.y
@@ -10182,8 +10182,11 @@ rb_enc_symname_p(const char *name, rb_encoding *enc)
     return rb_enc_symname2_p(name, strlen(name), enc);
 }
 
+#define IDSET_ATTRSET_FOR_SYNTAX ((1U<<ID_LOCAL)|(1U<<ID_CONST))
+#define IDSET_ATTRSET_FOR_INTERN (~(~0U<<ID_SCOPE_MASK) & ~(1U<<ID_ATTRSET))
+
 static int
-rb_enc_symname_type(const char *name, long len, rb_encoding *enc)
+rb_enc_symname_type(const char *name, long len, rb_encoding *enc, unsigned int allowed_atttset)
 {
     const char *m = name;
     const char *e = m + len;
@@ -10267,7 +10270,7 @@ rb_enc_symname_type(const char *name, long len, rb_encoding *enc)
 	    ++m;
 	    break;
 	  case '=':
-	    if (type != ID_CONST && type != ID_LOCAL) return -1;
+	    if (!(allowed_atttset & (1U << type))) return -1;
 	    type = ID_ATTRSET;
 	    ++m;
 	    break;
@@ -10280,15 +10283,15 @@ rb_enc_symname_type(const char *name, long len, rb_encoding *enc)
 int
 rb_enc_symname2_p(const char *name, long len, rb_encoding *enc)
 {
-    return rb_enc_symname_type(name, len, enc) != -1;
+    return rb_enc_symname_type(name, len, enc, IDSET_ATTRSET_FOR_SYNTAX) != -1;
 }
 
 static int
-rb_str_symname_type(VALUE name)
+rb_str_symname_type(VALUE name, unsigned int allowed_atttset)
 {
     const char *ptr = StringValuePtr(name);
     long len = RSTRING_LEN(name);
-    int type = rb_enc_symname_type(ptr, len, rb_enc_get(name));
+    int type = rb_enc_symname_type(ptr, len, rb_enc_get(name), allowed_atttset);
     RB_GC_GUARD(name);
     return type;
 }
@@ -10719,43 +10722,43 @@ rb_check_id_cstr(const char *ptr, long len, rb_encoding *enc)
 int
 rb_is_const_name(VALUE name)
 {
-    return rb_str_symname_type(name) == ID_CONST;
+    return rb_str_symname_type(name, 0) == ID_CONST;
 }
 
 int
 rb_is_class_name(VALUE name)
 {
-    return rb_str_symname_type(name) == ID_CLASS;
+    return rb_str_symname_type(name, 0) == ID_CLASS;
 }
 
 int
 rb_is_global_name(VALUE name)
 {
-    return rb_str_symname_type(name) == ID_GLOBAL;
+    return rb_str_symname_type(name, 0) == ID_GLOBAL;
 }
 
 int
 rb_is_instance_name(VALUE name)
 {
-    return rb_str_symname_type(name) == ID_INSTANCE;
+    return rb_str_symname_type(name, 0) == ID_INSTANCE;
 }
 
 int
 rb_is_attrset_name(VALUE name)
 {
-    return rb_str_symname_type(name) == ID_ATTRSET;
+    return rb_str_symname_type(name, IDSET_ATTRSET_FOR_INTERN) == ID_ATTRSET;
 }
 
 int
 rb_is_local_name(VALUE name)
 {
-    return rb_str_symname_type(name) == ID_LOCAL;
+    return rb_str_symname_type(name, 0) == ID_LOCAL;
 }
 
 int
 rb_is_method_name(VALUE name)
 {
-    switch (rb_str_symname_type(name)) {
+    switch (rb_str_symname_type(name, 0)) {
       case ID_LOCAL: case ID_ATTRSET: case ID_JUNK:
 	return TRUE;
     }
@@ -10765,7 +10768,7 @@ rb_is_method_name(VALUE name)
 int
 rb_is_junk_name(VALUE name)
 {
-    return rb_str_symname_type(name) == -1;
+    return rb_str_symname_type(name, IDSET_ATTRSET_FOR_SYNTAX) == -1;
 }
 
 #endif /* !RIPPER */
diff --git a/test/ruby/test_struct.rb b/test/ruby/test_struct.rb
index 677452879c..1bcc485410 100644
--- a/test/ruby/test_struct.rb
+++ b/test/ruby/test_struct.rb
@@ -131,7 +131,15 @@ class TestStruct < Test::Unit::TestCase
 
     klass = Struct.new(:@a)
     o = klass.new(1)
+    assert_equal(1, o.__send__(:@a))
     assert_equal("#<struct :@a=1>", o.inspect)
+    o.__send__(:"@a=", 2)
+    assert_equal(2, o.__send__(:@a))
+    assert_equal("#<struct :@a=2>", o.inspect)
+    o.__send__("@a=", 3)
+    assert_equal(3, o.__send__(:@a))
+    assert_equal("#<struct :@a=3>", o.inspect)
+
     methods = klass.instance_methods(false)
     assert_equal([:@a, :"@a="].inspect, methods.inspect, '[Bug #8756]')
     assert_include(methods, :@a)