object.c (rb_class_real): do not dereference 0 VALUE

* test/ruby/test_module.rb (test_inspect_segfault):
  Test case and bug report by Thomas Stratmann.
  [ruby-core:65214] [Bug #10282]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@47715 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 24 insertions, 0 deletions

diff --git a/test/ruby/test_module.rb b/test/ruby/test_module.rb
index ce5ab2ff73..f025c1948e 100644
--- a/test/ruby/test_module.rb
+++ b/test/ruby/test_module.rb
@@ -1971,6 +1971,30 @@ class TestModule < Test::Unit::TestCase
     }
   end
 
+  def test_inspect_segfault
+    bug_10282 = '[ruby-core:65214] [Bug #10282]'
+    assert_separately [], <<-RUBY
+      module ShallowInspect
+        def shallow_inspect
+          "foo"
+        end
+      end
+
+      module InspectIsShallow
+        include ShallowInspect
+        alias_method :inspect, :shallow_inspect
+      end
+
+      class A
+      end
+
+      A.prepend InspectIsShallow
+
+      expect = "#<Method: A(Object)#inspect(shallow_inspect)>"
+      assert_equal expect, A.new.method(:inspect).inspect, "#{bug_10282}"
+    RUBY
+  end
+
   private
 
   def assert_top_method_is_private(method)