Remove unnecessary module flag, add module assertions to other module flags

6 files changed, 11 insertions, 23 deletions

diff --git a/class.c b/class.c
index e752cf87d9..0255a7c7e6 100644
--- a/class.c
+++ b/class.c
@@ -1268,11 +1268,12 @@ do_include_modules_at(const VALUE klass, VALUE c, VALUE module, int search_super
             rb_module_add_to_subclasses_list(m, iclass);
 	}
 
-	if (FL_TEST(klass, RMODULE_IS_REFINEMENT)) {
+	if (BUILTIN_TYPE(klass) == T_MODULE && FL_TEST(klass, RMODULE_IS_REFINEMENT)) {
 	    VALUE refined_class =
 		rb_refinement_module_get_refined_class(klass);
 
             rb_id_table_foreach(RCLASS_M_TBL(module), add_refined_method_entry_i, (void *)refined_class);
+            RUBY_ASSERT(BUILTIN_TYPE(c) == T_MODULE);
 	    FL_SET(c, RMODULE_INCLUDED_INTO_REFINEMENT);
 	}
 
@@ -1497,7 +1498,7 @@ rb_mod_ancestors(VALUE mod)
 {
     VALUE p, ary = rb_ary_new();
     VALUE refined_class = Qnil;
-    if (FL_TEST(mod, RMODULE_IS_REFINEMENT)) {
+    if (BUILTIN_TYPE(mod) == T_MODULE && FL_TEST(mod, RMODULE_IS_REFINEMENT)) {
         refined_class = rb_refinement_module_get_refined_class(mod);
     }
 
diff --git a/eval.c b/eval.c
index 237c0fbd66..a059987824 100644
--- a/eval.c
+++ b/eval.c
@@ -1129,7 +1129,7 @@ rb_mod_include(int argc, VALUE *argv, VALUE module)
     CONST_ID(id_append_features, "append_features");
     CONST_ID(id_included, "included");
 
-    if (FL_TEST(module, RMODULE_IS_REFINEMENT)) {
+    if (BUILTIN_TYPE(module) == T_MODULE && FL_TEST(module, RMODULE_IS_REFINEMENT)) {
         rb_raise(rb_eTypeError, "Refinement#include has been removed");
     }
 
@@ -1183,7 +1183,7 @@ rb_mod_prepend(int argc, VALUE *argv, VALUE module)
     int i;
     ID id_prepend_features, id_prepended;
 
-    if (FL_TEST(module, RMODULE_IS_REFINEMENT)) {
+    if (BUILTIN_TYPE(module) == T_MODULE && FL_TEST(module, RMODULE_IS_REFINEMENT)) {
         rb_raise(rb_eTypeError, "Refinement#prepend has been removed");
     }
 
@@ -1264,7 +1264,6 @@ rb_using_refinement(rb_cref_t *cref, VALUE klass, VALUE module)
 	    }
 	}
     }
-    FL_SET(module, RMODULE_IS_OVERLAID);
     superclass = refinement_superclass(superclass);
     c = iclass = rb_include_class_new(module, superclass);
     RB_OBJ_WRITE(c, &RCLASS_REFINED_CLASS(c), klass);
@@ -1273,7 +1272,6 @@ rb_using_refinement(rb_cref_t *cref, VALUE klass, VALUE module)
 
     module = RCLASS_SUPER(module);
     while (module && module != klass) {
-	FL_SET(module, RMODULE_IS_OVERLAID);
 	c = RCLASS_SET_SUPER(c, rb_include_class_new(module, RCLASS_SUPER(c)));
         RB_OBJ_WRITE(c, &RCLASS_REFINED_CLASS(c), klass);
         module = RCLASS_SUPER(module);
@@ -1362,13 +1360,11 @@ add_activated_refinement(VALUE activated_refinements,
 	    c = RCLASS_SUPER(c);
 	}
     }
-    FL_SET(refinement, RMODULE_IS_OVERLAID);
     superclass = refinement_superclass(superclass);
     c = iclass = rb_include_class_new(refinement, superclass);
     RB_OBJ_WRITE(c, &RCLASS_REFINED_CLASS(c), klass);
     refinement = RCLASS_SUPER(refinement);
     while (refinement && refinement != klass) {
-	FL_SET(refinement, RMODULE_IS_OVERLAID);
 	c = RCLASS_SET_SUPER(c, rb_include_class_new(refinement, RCLASS_SUPER(c)));
         RB_OBJ_WRITE(c, &RCLASS_REFINED_CLASS(c), klass);
 	refinement = RCLASS_SUPER(refinement);
@@ -1421,6 +1417,7 @@ rb_mod_refine(VALUE module, VALUE klass)
 	VALUE superclass = refinement_superclass(klass);
 	refinement = rb_refinement_new();
 	RCLASS_SET_SUPER(refinement, superclass);
+        RUBY_ASSERT(BUILTIN_TYPE(refinement) == T_MODULE);
 	FL_SET(refinement, RMODULE_IS_REFINEMENT);
 	CONST_ID(id_refined_class, "__refined_class__");
 	rb_ivar_set(refinement, id_refined_class, klass);
@@ -1511,7 +1508,7 @@ used_modules_i(VALUE _, VALUE mod, VALUE ary)
 {
     ID id_defined_at;
     CONST_ID(id_defined_at, "__defined_at__");
-    while (FL_TEST(rb_class_of(mod), RMODULE_IS_REFINEMENT)) {
+    while (BUILTIN_TYPE(rb_class_of(mod)) == T_MODULE && FL_TEST(rb_class_of(mod), RMODULE_IS_REFINEMENT)) {
 	rb_ary_push(ary, rb_attr_get(rb_class_of(mod), id_defined_at));
 	mod = RCLASS_SUPER(mod);
     }
@@ -1562,7 +1559,7 @@ rb_mod_s_used_modules(VALUE _)
 static int
 used_refinements_i(VALUE _, VALUE mod, VALUE ary)
 {
-    while (FL_TEST(rb_class_of(mod), RMODULE_IS_REFINEMENT)) {
+    while (BUILTIN_TYPE(rb_class_of(mod)) == T_MODULE && FL_TEST(rb_class_of(mod), RMODULE_IS_REFINEMENT)) {
         rb_ary_push(ary, rb_class_of(mod));
 	mod = RCLASS_SUPER(mod);
     }
diff --git a/include/ruby/internal/core/rclass.h b/include/ruby/internal/core/rclass.h
index 13a33a28bd..6d450917db 100644
--- a/include/ruby/internal/core/rclass.h
+++ b/include/ruby/internal/core/rclass.h
@@ -26,7 +26,6 @@
 #include "ruby/internal/cast.h"
 
 /** @cond INTERNAL_MACRO */
-#define RMODULE_IS_OVERLAID              RMODULE_IS_OVERLAID
 #define RMODULE_IS_REFINEMENT            RMODULE_IS_REFINEMENT
 #define RMODULE_INCLUDED_INTO_REFINEMENT RMODULE_INCLUDED_INTO_REFINEMENT
 /** @endcond */
@@ -55,15 +54,6 @@
  * Why is it here, given RClass itself is not?
  */
 enum ruby_rmodule_flags {
-
-    /**
-     * This flag has something to do with refinements... I guess?  It is set on
-     * occasions  for modules  that are  refined by  refinements, but  it seems
-     * ...  nobody cares  about  such things?   Not sure  but  this flag  could
-     * perhaps be a write-only information.
-     */
-    RMODULE_IS_OVERLAID              = RUBY_FL_USER2,
-
     /**
      * This flag has something to do  with refinements.  A module created using
      * rb_mod_refine()  has this  flag set.   This  is the  bit which  controls
diff --git a/vm_insnhelper.c b/vm_insnhelper.c
index 2eb9fd8630..1e40088ffa 100644
--- a/vm_insnhelper.c
+++ b/vm_insnhelper.c
@@ -3798,6 +3798,7 @@ static inline VALUE
 vm_search_normal_superclass(VALUE klass)
 {
     if (BUILTIN_TYPE(klass) == T_ICLASS &&
+            RB_TYPE_P(RBASIC(klass)->klass, T_MODULE) &&
 	FL_TEST_RAW(RBASIC(klass)->klass, RMODULE_IS_REFINEMENT)) {
 	klass = RBASIC(klass)->klass;
     }
@@ -3840,7 +3841,6 @@ vm_search_super_method(const rb_control_frame_t *reg_cfp, struct rb_call_data *c
     }
 
     if (BUILTIN_TYPE(current_defined_class) != T_MODULE &&
-	!FL_TEST_RAW(current_defined_class, RMODULE_INCLUDED_INTO_REFINEMENT) &&
         reg_cfp->iseq != method_entry_iseqptr(me) &&
         !rb_obj_is_kind_of(recv, current_defined_class)) {
 	VALUE m = RB_TYPE_P(current_defined_class, T_ICLASS) ?
diff --git a/vm_method.c b/vm_method.c
index a10f90e7a3..b12d134dce 100644
--- a/vm_method.c
+++ b/vm_method.c
@@ -858,7 +858,7 @@ rb_method_entry_make(VALUE klass, ID mid, VALUE defined_class, rb_method_visibil
        rb_class_modify_check(klass);
     }
 
-    if (FL_TEST(klass, RMODULE_IS_REFINEMENT)) {
+    if (RB_TYPE_P(klass, T_MODULE) && FL_TEST(klass, RMODULE_IS_REFINEMENT)) {
 	VALUE refined_class = rb_refinement_module_get_refined_class(klass);
 	rb_add_refined_method_entry(refined_class, mid);
     }
diff --git a/yjit/src/codegen.rs b/yjit/src/codegen.rs
index e64f269cfe..3591e05b3d 100644
--- a/yjit/src/codegen.rs
+++ b/yjit/src/codegen.rs
@@ -5035,7 +5035,7 @@ fn gen_invokesuper(
     // vm_search_normal_superclass
     let rbasic_ptr: *const RBasic = current_defined_class.as_ptr();
     if current_defined_class.builtin_type() == RUBY_T_ICLASS
-        && unsafe { FL_TEST_RAW((*rbasic_ptr).klass, VALUE(RMODULE_IS_REFINEMENT)) != VALUE(0) }
+        && unsafe { RB_TYPE_P((*rbasic_ptr).klass, RUBY_T_MODULE) && FL_TEST_RAW((*rbasic_ptr).klass, VALUE(RMODULE_IS_REFINEMENT)) != VALUE(0) }
     {
         return CantCompile;
     }