diff --git a/spec/ruby/core/process/groups_spec.rb b/spec/ruby/core/process/groups_spec.rb
index 2e12aa350c..8b76bc7932 100644
--- a/spec/ruby/core/process/groups_spec.rb
+++ b/spec/ruby/core/process/groups_spec.rb
@@ -53,9 +53,8 @@ describe "Process.groups=" do
 
       platform_is_not :aix do
         it "raises Errno::EPERM" do
-          groups = Process.groups
           lambda {
-            Process.groups = groups
+            Process.groups = [0]
           }.should raise_error(Errno::EPERM)
         end
       end