Revert "merge revision(s) ff222ac: [Backport #21370]"

This reverts commit acb19e8.

Author: k0kubun

compile.c

@@ -13234,13 +13234,6 @@ outer_variable_cmp(const void *a, const void *b, void *arg)
 {
     const struct outer_variable_pair *ap = (const struct outer_variable_pair *)a;
     const struct outer_variable_pair *bp = (const struct outer_variable_pair *)b;
-
-    if (!ap->name) {
-        return -1;
-    } else if (!bp->name) {
-        return 1;
-    }
-
     return rb_str_cmp(ap->name, bp->name);
 }
 

test/ruby/test_iseq.rb

@@ -905,25 +905,6 @@ def test_unreachable_next_in_block
     end
   end
 
-  def test_serialize_anonymous_outer_variables
-    iseq = RubyVM::InstructionSequence.compile(<<~'RUBY')
-      obj = Object.new
-      def obj.test
-        [1].each do
-          raise "Oops"
-        rescue
-          return it
-        end
-      end
-      obj
-    RUBY
-
-    binary = iseq.to_binary # [Bug # 21370]
-    roundtripped_iseq = RubyVM::InstructionSequence.load_from_binary(binary)
-    object = roundtripped_iseq.eval
-    assert_equal 1, object.test
-  end
-
   def test_loading_kwargs_memory_leak
     assert_no_memory_leak([], "#{<<~"begin;"}", "#{<<~'end;'}", rss: true)
     a = RubyVM::InstructionSequence.compile("foo(bar: :baz)").to_binary