refactor constify most of rb_method_definition_t

Most (if not all) of the fields of rb_method_definition_t are never
meant to be modified once after they are stored.  Marking them const
makes it possible for compilers to warn on unintended modifications.

1 files changed, 1 insertions, 1 deletions

diff --git a/gc.c b/gc.c
index c9f26cc174..0caee4c260 100644
--- a/gc.c
+++ b/gc.c
@@ -7831,7 +7831,7 @@ void rb_update_st_references(struct st_table *ht)
 static void
 gc_ref_update_method_entry(rb_objspace_t *objspace, rb_method_entry_t *me)
 {
-    rb_method_definition_t *def = me->def;
+    const rb_method_definition_t *def = me->def;
 
     UPDATE_IF_MOVED(objspace, me->owner);
     UPDATE_IF_MOVED(objspace, me->defined_class);