[ruby-core:116388] [BUG] leak in deprecated Data_Make_Struct

  I can't open new bug on Redmine due to TOTP so I'll post here.
  (I'm not going to run JS, view images, or deal with proprietary
  tools/services).

I realize Data_Make_Struct is deprecated and I'm updating a gem
to TypedData, there's likely old code which is affected by this
leak.

With the patch below to make data_spec.c use Data_Make_Struct,
this script leaks:

  $LOAD_PATH << './spec/ruby/optional/capi/ext'
  require 'data_spec'
  loop { CApiAllocSpecs.Data_Make_Struct }

I noticed this on Ruby 3.3 (32-bit x86) with `clogger' RubyGem,
and also up to recent master commit c0cabc0a699b2c8b
(Dump annotations on RubyVM::ISeq.disasm (#9667), 2024-01-23)
---
 Not sure how to write a Ruby spec for malloc memory leaks but
 I'm just a drive by contributor at this point.  It takes
 me 2-3 hours to build and test Ruby on my old system so I don't
 feel like doing more.

 spec/ruby/optional/capi/ext/data_spec.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/spec/ruby/optional/capi/ext/data_spec.c b/spec/ruby/optional/capi/ext/data_spec.c
index ef069ef0ba..450eef6c76 100644
--- a/spec/ruby/optional/capi/ext/data_spec.c
+++ b/spec/ruby/optional/capi/ext/data_spec.c
@@ -24,6 +24,11 @@ VALUE sdaf_alloc_func(VALUE klass) {
   return Data_Wrap_Struct(klass, &sample_wrapped_struct_mark, &sample_wrapped_struct_free, bar);
 }
 
+VALUE sdaf_make_struct(VALUE klass) {
+  struct sample_wrapped_struct* bar;
+  return Data_Make_Struct(klass, struct sample_wrapped_struct, sample_wrapped_struct_mark, RUBY_DEFAULT_FREE, bar);
+}
+
 VALUE sdaf_get_struct(VALUE self) {
   struct sample_wrapped_struct* bar;
   Data_Get_Struct(self, struct sample_wrapped_struct, bar);
@@ -74,6 +79,7 @@ VALUE sws_rb_check_type(VALUE self, VALUE obj, VALUE other) {
 void Init_data_spec(void) {
   VALUE cls = rb_define_class("CApiAllocSpecs", rb_cObject);
   rb_define_alloc_func(cls, sdaf_alloc_func);
+  rb_define_singleton_method(cls, "Data_Make_Struct", sdaf_make_struct, 0);
   rb_define_method(cls, "wrapped_data", sdaf_get_struct, 0);
   cls = rb_define_class("CApiWrappedStructSpecs", rb_cObject);
   rb_define_method(cls, "wrap_struct", sws_wrap_struct, 1);
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