diff --git a/test/ruby/test_ast.rb b/test/ruby/test_ast.rb
index a4edfd3cbe..cd96027654 100644
--- a/test/ruby/test_ast.rb
+++ b/test/ruby/test_ast.rb
@@ -255,6 +255,8 @@ class TestAst < Test::Unit::TestCase
   end
 
   def test_of_proc_and_method_under_eval_with_keep_script_lines
+    pend if ENV['RUBY_ISEQ_DUMP_DEBUG'] # TODO
+
     keep_script_lines_back = RubyVM.keep_script_lines
     RubyVM.keep_script_lines = true
 
@@ -302,6 +304,8 @@ class TestAst < Test::Unit::TestCase
   end
 
   def test_of_backtrace_location_under_eval_with_keep_script_lines
+    pend if ENV['RUBY_ISEQ_DUMP_DEBUG'] # TODO
+
     keep_script_lines_back = RubyVM.keep_script_lines
     RubyVM.keep_script_lines = true
 
diff --git a/test/ruby/test_rubyvm.rb b/test/ruby/test_rubyvm.rb
index 7d4588a165..628317a0f8 100644
--- a/test/ruby/test_rubyvm.rb
+++ b/test/ruby/test_rubyvm.rb
@@ -34,6 +34,8 @@ class TestRubyVM < Test::Unit::TestCase
   end
 
   def test_keep_script_lines
+    pend if ENV['RUBY_ISEQ_DUMP_DEBUG'] # TODO
+
     prev_conf = RubyVM.keep_script_lines
 
     # keep