diff --git a/object.c b/object.c
index 99950d477f..5e5329a5f8 100644
--- a/object.c
+++ b/object.c
@@ -339,7 +339,7 @@ rb_obj_copy_ivar(VALUE dest, VALUE obj)
     shape_id_t dest_shape_id = src_shape_id;
     shape_id_t initial_shape_id = RBASIC_SHAPE_ID(dest);
 
-    if (RSHAPE(initial_shape_id)->heap_index != RSHAPE(src_shape_id)->heap_index || !rb_shape_id_canonical_p(src_shape_id)) {
+    if (RSHAPE(initial_shape_id)->heap_index != RSHAPE(src_shape_id)->heap_index || !rb_shape_canonical_p(src_shape_id)) {
         RUBY_ASSERT(RSHAPE(initial_shape_id)->type == SHAPE_T_OBJECT);
 
         dest_shape_id = rb_shape_rebuild(initial_shape_id, src_shape_id);
diff --git a/shape.h b/shape.h
index 91f1931290..b58eebd4d3 100644
--- a/shape.h
+++ b/shape.h
@@ -142,7 +142,7 @@ void rb_shape_copy_fields(VALUE dest, VALUE *dest_buf, shape_id_t dest_shape_id,
 void rb_shape_copy_complex_ivars(VALUE dest, VALUE obj, shape_id_t src_shape_id, st_table *fields_table);
 
 static inline bool
-rb_shape_id_canonical_p(shape_id_t shape_id)
+rb_shape_canonical_p(shape_id_t shape_id)
 {
     return !RSHAPE(shape_id)->flags;
 }
diff --git a/variable.c b/variable.c
index c29ca02390..f7ba33e089 100644
--- a/variable.c
+++ b/variable.c
@@ -1659,7 +1659,7 @@ rb_obj_init_too_complex(VALUE obj, st_table *table)
 {
     // This method is meant to be called on newly allocated object.
     RUBY_ASSERT(!rb_shape_obj_too_complex_p(obj));
-    RUBY_ASSERT(rb_shape_id_canonical_p(RBASIC_SHAPE_ID(obj)));
+    RUBY_ASSERT(rb_shape_canonical_p(RBASIC_SHAPE_ID(obj)));
     RUBY_ASSERT(RSHAPE_LEN(RBASIC_SHAPE_ID(obj)) == 0);
 
     obj_transition_too_complex(obj, table);
@@ -2340,7 +2340,7 @@ rb_copy_generic_ivar(VALUE dest, VALUE obj)
         shape_id_t dest_shape_id = src_shape_id;
         shape_id_t initial_shape_id = rb_obj_shape_id(dest);
 
-        if (!rb_shape_id_canonical_p(src_shape_id)) {
+        if (!rb_shape_canonical_p(src_shape_id)) {
             RUBY_ASSERT(RSHAPE(initial_shape_id)->type == SHAPE_ROOT);
 
             dest_shape_id = rb_shape_rebuild(initial_shape_id, src_shape_id);