<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/138194>138194</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Crash in lld with thin LTO cache and assembly output
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            lld
      </td>
    </tr>

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

    <tr>
      <th>Reporter</th>
      <td>
          quic-akaryaki
      </td>
    </tr>
</table>

<pre>
    After #136121 is merged, thin LTO with assembly output with cache crashes lld. A test case is basic:

`int main() { return 0; }`

```
clang -c main.c -O2 -flto=thin -o main.o
ld.lld --thinlto-cache-dir=. --lto-emit-asm -e main main.o
```
The crash happens in the destructor of MCAsmStreamer, which tries to close a stream that it was passed. However, the stream was previously closed while calling the commit() function in LTOBackend.cpp: codegen().

A simple fix would be to delete the LTO pipeline before the stream commit function is called in LTOBackend.cpp: codegen().

</pre>
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