diff --git a/test/ruby/test_symbol.rb b/test/ruby/test_symbol.rb
index f24bb81583..0cc760ae00 100644
--- a/test/ruby/test_symbol.rb
+++ b/test/ruby/test_symbol.rb
@@ -223,8 +223,14 @@ class TestSymbol < Test::Unit::TestCase
   end
 
   def test_symol_gc_1
+    assert_normal_exit('".".intern;GC.start(immediate_sweep:false);eval %[GC.start;".".intern]',
+                       '',
+                       child_env: '--disable-gems')
     assert_normal_exit('".".intern;GC.start(immediate_sweep:false);eval %[GC.start;:"."]',
                        '',
                        child_env: '--disable-gems')
+    assert_normal_exit('".".intern;GC.start(immediate_sweep:false);eval %[GC.start;%i"."]',
+                       '',
+                       child_env: '--disable-gems')
   end
 end