nobu	2018-04-03 15:57:44 +0900 (Tue, 03 Apr 2018)

  New Revision: 63068

  https://svn.ruby-lang.org/cgi-bin/viewvc.cgi?view=revision&revision=63068

  Log:
    proc.c: fix segfault when no singleton class
    
    * proc.c (rb_obj_singleton_method): bail out if the receiver does
      not have the singleton class without accessing the origin class
      not to segfault.  [Bug #14658]

  Modified files:
    trunk/proc.c
    trunk/test/ruby/test_method.rb
Index: test/ruby/test_method.rb
===================================================================
--- test/ruby/test_method.rb	(revision 63067)
+++ test/ruby/test_method.rb	(revision 63068)
@@ -790,6 +790,9 @@ class TestMethod < Test::Unit::TestCase https://github.com/ruby/ruby/blob/trunk/test/ruby/test_method.rb#L790
     class << o; prepend Module.new; end
     m = assert_nothing_raised(NameError, bug14658) {o.singleton_method(:bar)}
     assert_equal(:bar, m.call, bug14658)
+
+    o = Object.new
+    assert_raise(NameError, bug14658) {o.singleton_method(:bar)}
   end
 
   Feature9783 = '[ruby-core:62212] [Feature #9783]'
Index: proc.c
===================================================================
--- proc.c	(revision 63067)
+++ proc.c	(revision 63068)
@@ -1771,21 +1771,23 @@ VALUE https://github.com/ruby/ruby/blob/trunk/proc.c#L1771
 rb_obj_singleton_method(VALUE obj, VALUE vid)
 {
     const rb_method_entry_t *me;
-    VALUE klass = RCLASS_ORIGIN(rb_singleton_class_get(obj));
+    VALUE klass = rb_singleton_class_get(obj);
     ID id = rb_check_id(&vid);
 
+    if (NIL_P(klass) || NIL_P(klass = RCLASS_ORIGIN(klass))) {
+      undef:
+	rb_name_err_raise("undefined singleton method `%1$s' for `%2$s'",
+			  obj, vid);
+    }
     if (!id) {
-	if (!NIL_P(klass) &&
-	    respond_to_missing_p(klass, obj, vid, FALSE)) {
+	if (respond_to_missing_p(klass, obj, vid, FALSE)) {
 	    id = rb_intern_str(vid);
 	    return mnew_missing(klass, obj, id, rb_cMethod);
 	}
-      undef:
-	rb_name_err_raise("undefined singleton method `%1$s' for `%2$s'",
-			  obj, vid);
+	goto undef;
     }
-    if (NIL_P(klass) ||
-	UNDEFINED_METHOD_ENTRY_P(me = rb_method_entry_at(klass, id)) ||
+    me = rb_method_entry_at(klass, id);
+    if (UNDEFINED_METHOD_ENTRY_P(me) ||
 	UNDEFINED_REFINED_METHOD_P(me->def)) {
 	vid = ID2SYM(id);
 	goto undef;

--
ML: ruby-changes@q...
Info: http://www.atdot.net/~ko1/quickml/