diff --git a/gc.c b/gc.c
index 8900279d99..b95094b385 100644
--- a/gc.c
+++ b/gc.c
@@ -10493,13 +10493,15 @@ static const rb_data_type_t weakmap_type = {
     0, 0, RUBY_TYPED_FREE_IMMEDIATELY
 };
 
+extern const struct st_hash_type rb_hashtype_ident;
+
 static VALUE
 wmap_allocate(VALUE klass)
 {
     struct weakmap *w;
     VALUE obj = TypedData_Make_Struct(klass, struct weakmap, &weakmap_type, w);
-    w->obj2wmap = st_init_numtable();
-    w->wmap2obj = st_init_numtable();
+    w->obj2wmap = st_init_table(&rb_hashtype_ident);
+    w->wmap2obj = st_init_table(&rb_hashtype_ident);
     w->final = rb_obj_method(obj, ID2SYM(rb_intern("finalize")));
     return obj;
 }
diff --git a/hash.c b/hash.c
index 9b5f978dd9..b73ade7c01 100644
--- a/hash.c
+++ b/hash.c
@@ -330,7 +330,8 @@ rb_ident_hash(st_data_t n)
     return (st_index_t)st_index_hash((st_index_t)n);
 }
 
-static const struct st_hash_type identhash = {
+#define identhash rb_hashtype_ident
+const struct st_hash_type rb_hashtype_ident = {
     rb_ident_cmp,
     rb_ident_hash,
 };