hash.c: fix memory leak

* hash.c (env_shift): fix memory leak on Windows, free environment
  strings block always.  [ruby-dev:48332] [Bug #9983]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@46570 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,8 @@
+Fri Jun 27 05:33:26 2014  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* hash.c (env_shift): fix memory leak on Windows, free environment
+	  strings block always.  [ruby-dev:48332] [Bug #9983]
+
 Fri Jun 27 03:41:53 2014  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* sprintf.c (GETASTER): should not use the numbered argument to be

hash.c

@@ -3554,6 +3554,7 @@ static VALUE
 env_shift(void)
 {
     char **env;
+    VALUE result = Qnil;
 
     env = GET_ENVIRON(environ);
     if (*env) {
@@ -3562,11 +3563,11 @@ env_shift(void)
 	    VALUE key = env_str_new(*env, s-*env);
 	    VALUE val = env_str_new2(getenv(RSTRING_PTR(key)));
 	    env_delete(Qnil, key);
-	    return rb_assoc_new(key, val);
+	    result = rb_assoc_new(key, val);
 	}
     }
     FREE_ENVIRON(environ);
-    return Qnil;
+    return result;
 }
 
 /*

test/ruby/test_env.rb

@@ -533,4 +533,13 @@ class TestEnv < Test::Unit::TestCase
       ENV.select {ENV.clear}
     end;
   end
+
+  def test_memory_leak_shift
+    bug9983 = '[ruby-dev:48332] [Bug #9983]'
+    assert_no_memory_leak([], <<-'end;', "5_000.times {ENV.shift; ENV[k] = v}", bug9983)
+      ENV.clear
+      k = 'FOO'
+      v = (ENV[k] = 'bar'*5000 rescue 'bar'*1500)
+    end;
+  end
 end