<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/113747>113747</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [clang] __attribute__((__noreturn__)) miscompile
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            clang
      </td>
    </tr>

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

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

<pre>
    `__attribute__((__noreturn__))` is miscompiled upstream.
See https://godbolt.org/z/T6nMoa75G from Miguel Young and his comment.

```
When using the standard [[noreturn]] and _Noreturn in their respective languages, codegen is identical, and correct. The C codegen is obviously wrong and clearly confusing the hell out of LLVM, as evidenced by this instruction sequence:

    jne     .LBB1_1
 mov     rax, qword ptr [rip + baz@GOTPCREL]
    call    rax
.LBB1_1: mov rax, qword ptr [rip + foo@GOTPCREL] call rax

(Just do call foo@PLT?)

My recommendation is that upstream use _Noreturn, or noreturn + <stdnoreturn.h>. Clang is clearly able to get this right, but somehow left hand isn't talking to right hand in the unification algorithm.

(This really isn't a C v. C++ difference at all; both languages define their standard noreturn primitives identically.)
```

</pre>
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