array.c (ary_recycle_hash): use rb_gc_force_recycle

Hidden objects (RBASIC_CLASS(hash) == 0) can never become
visible to other threads or signal handlers via
ObjectSpace.each_object or similar means.  Thus it is safe to
forcibly recycle the object slot for future use, here.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@57615 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

array.c

@@ -4095,12 +4095,12 @@ ary_make_hash_by(VALUE ary)
 static inline void
 ary_recycle_hash(VALUE hash)
 {
+    assert(RBASIC_CLASS(hash) == 0);
     if (RHASH(hash)->ntbl) {
 	st_table *tbl = RHASH(hash)->ntbl;
-	RHASH(hash)->ntbl = 0;
 	st_free_table(tbl);
     }
-    RB_GC_GUARD(hash);
+    rb_gc_force_recycle(hash);
 }
 
 /*