This test fail relatively frequently and it's unclear what is happening. ``` str: {"address":"0x7fbdeb26d4e0", "type":"STRING", "shape_id":1, "slot_size":40, "class":"0x7fbdd1e0ec50", "frozen":true, "embedded":true, "fstring":true, "bytesize":3, "value":"bar", "encoding":"UTF-8", "coderange":"7bit", "memsize":40, "flags":{"wb_protected":true, "old":true, "uncollectible":true, "marked":true}} bar: {"address":"0x7fbdd0a8b138", "type":"STRING", "shape_id":1, "slot_size":40, "class":"0x7fbdd1e0ec50", "frozen":true, "embedded":true, "fstring":true, "bytesize":3, "value":"bar", "encoding":"UTF-8", "coderange":"7bit", "memsize":40, "flags":{"wb_protected":true}} ``` The `"bar".freeze` literal correctly put an old-gen fstring on the stack. But `-%w(b a r).join('')` returns a young-gen fstring, which suggest it somehow failed to find the old one in the `frozen_strings` table. This could be caused by another test corrupting the table, or corrupting the `"bar"` fstring. By using a different literal value we can learn whether the bug is specific to `"bar"` (used in many tests) or more general.