enumerator.c: should not store local variable address

* enumerator.c (enumerator_with_index): should not store local variable
  address to memoise the arguments.  it is invalidated after the return.
  [ruby-core:58692] [Bug #9178]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@43929 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,9 @@
+Sat Nov 30 16:25:14 2013  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* enumerator.c (enumerator_with_index): should not store local variable
+	  address to memoise the arguments.  it is invalidated after the return.
+	  [ruby-core:58692] [Bug #9178]
+
 Sat Nov 30 13:28:13 2013  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* siphash.c (sip_hash24): fix for aligned word access little endian

enumerator.c

@@ -495,9 +495,9 @@ enumerator_each(int argc, VALUE *argv, VALUE obj)
 static VALUE
 enumerator_with_index_i(RB_BLOCK_CALL_FUNC_ARGLIST(val, m))
 {
-    VALUE *memo = (VALUE *)m;
-    VALUE idx = *memo;
-    *memo = rb_int_succ(idx);
+    NODE *memo = (NODE *)m;
+    VALUE idx = memo->u1.value;
+    memo->u1.value = rb_int_succ(idx);
 
     if (argc <= 1)
 	return rb_yield_values(2, val, idx);
@@ -537,7 +537,7 @@ enumerator_with_index(int argc, VALUE *argv, VALUE obj)
 	memo = INT2FIX(0);
     else
 	memo = rb_to_int(memo);
-    return enumerator_block_call(obj, enumerator_with_index_i, (VALUE)&memo);
+    return enumerator_block_call(obj, enumerator_with_index_i, (VALUE)NEW_MEMO(memo, 0, 0));
 }
 
 /*

test/ruby/test_enumerator.rb

@@ -134,6 +134,16 @@ class TestEnumerator < Test::Unit::TestCase
     assert_raise(TypeError, bug8010){ @obj.to_enum(:foo, 1, 2, 3).with_index('1').to_a }
   end
 
+  def test_with_index_dangling_memo
+    bug9178 = '[ruby-core:58692] [Bug #9178]'
+    assert_separately([], <<-"end;")
+    bug = "#{bug9178}"
+    e = [1].to_enum(:chunk).with_index {|c,i| i == 5}
+    assert_kind_of(Enumerator, e)
+    assert_equal([false, [1]], e.to_a[0], bug)
+    end;
+  end
+
   def test_with_object
     obj = [0, 1]
     ret = (1..10).each.with_object(obj) {|i, memo|