<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=http://email.email.llvm.org/c/eJylU9tu1DAQ_ZrkxdpVMo4T-yEPbRckVBBIVKJ99GW8MTjxEju7tF-Ps21VQYUQQkrmopmcnDljq2Du-8-IZEjpEAt6UcDb_OyDUcGnbZj3OXvI7xvGBvHpKCwp4IqkAUm8H0dMs9MkzXKKFmfiInHTUXpnZEJDYsiNMp278YccDx7JKSzeEJU_T1J_24QjztaHk5v2K-5pcHogcXhuksfgTEZS93_6ZTgkN7oHmVyYtkW1K6qLR3t582VFdGll9fE6EyM15AH_Oim_43fqA8frLbkZ1onWodIczKIzkwzzG4BLw6K2Oow58f747DaHOXxFnXKaa6NbAw6gBEiJDRW6URJE0wpeaS6hUwayb8GIShdAjbN2w7WFWhnJG80E7SiVshLCcmGxM7XorOEUKqpbpRvbWmW0EY3lSjXAWgP0fV1Tvsm26ciLvAY9Jox5PSP-oh85yBhz4WkLr8U2eMDJRJKlLk1PjaBClnJJQ5j7q2GR03d3u4hymX3_zyK5GBeMOWDARVsOPe2gsaZCY41qW6i1Rg6K6Y6rpuI1Lb1U6GNfsMsCIGuW3SVUOS7Yrvx_Bq6HCuoagFc0W7bVygJjdS14wxRDVjQVjtL57YqzHqBy7s-QatnHXPQupvhSzNq6_YT4RPhFryfGySV_Ll6FOSzJTZkL25F3jxdqvU6vFlKeKfdnvj8BbP07NA>52896</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [Coroutines] Invalided symmetric transfer
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            c++20
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
            ChuanqiXu9
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          ChuanqiXu9
      </td>
    </tr>
</table>

<pre>
    See https://godbolt.org/z/E55h9Pv9f , the symmetric transfer is invalidated so that the example would be stack-overflowing, which should be avoided by the symmetric transfer optimization.

BTW, it is OK in 12: https://godbolt.org/z/8Y8YbM8eK. This is introduced in https://github.com/llvm/llvm-project/commit/822b92aae439c4ba2946980c8a27bd2c8a62d90c#diff-8cf21bda84c593733aa099f89fe7d197fd83203c6bc4f6fbdcd94f8bb4256d23L1138-L1147 , which deletes some optimization passes which symmetric transfer depends on.
</pre>
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