<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/161608>161608</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            LLD ThinLto Issues with Swift codebase
        </td>
    </tr>

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

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

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

<pre>
    When using thin lto with Swift, we see a couple of LLD crashes.

All crashes seen so far are in  `AArch64 Instruction Selection` stages.

Setup:
1. Build with Xcode 16.4 toolchain.
2. Only use LLD for ThinLto.
3. Reproducer attached
4. `bazelisk build :Buttons --features=swift.thin_lto --features=thin_lto --features=swift.emit_bc --ios_multi_cpus=arm64`



```
LLVM ERROR: Unsupported stack probing method
PLEASE submit a bug report to https://github.com/llvm/llvm-project/issues/ and include the crash backtrace and instructions to reproduce the bug.
Stack dump:
0.      Running pass 'Function Pass Manager' on module 'bazel-out/ios_arm64-fastbuild-ios-arm64-min15.0-applebin_ios-ST-4adaf0076b5c/bin/libNeedleFoundation.a(NonCoreComponent.swift.bc)259720'.
1. Running pass 'AArch64 Instruction Selection' on function '@"$s16NeedleFoundation16NonCoreComponentC6parentACyxGAA5Scope_p_tcfC"'
```
</pre>
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