diff --git a/gc.c b/gc.c
index b036a81b8b..b11e39c2e0 100644
--- a/gc.c
+++ b/gc.c
@@ -2370,10 +2370,6 @@ newobj_init(VALUE klass, VALUE flags, int wb_protected, rb_objspace_t *objspace,
     return obj;
 }
 
-static inline void heap_add_freepage(rb_heap_t *heap, struct heap_page *page);
-static struct heap_page *heap_next_freepage(rb_objspace_t *objspace, rb_size_pool_t *size_pool, rb_heap_t *heap);
-static inline void ractor_set_cache(rb_ractor_t *cr, struct heap_page *page, size_t size_pool_idx);
-
 size_t
 rb_gc_obj_slot_size(VALUE obj)
 {