<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=http://email.email.llvm.org/c/eJylVF1zmzoQ_TX4ZceMER_GDzzYxsmkjd1MQnp7nzwCFqNGgEcSdf3vu4K4Tm57HzqdYUBoV7vnnN1V3pXnZFkZVMCPR3kW7QFMLTQUXdMI4_hLqI05alo47IaegzB1n7tkph8pv10-06PqvmJh6Pf1KLvxQlZGHo-ZV_J5xIOKB6HPkEdBnLMCPS8vFnwWocPW0JxBdgWXYINBinl_gLwXsoRCcV1jCdyAFO2LRagNPyDwtoRDZwgvQtVJeeqsDZXqFDgsbvg5RyhFVaHC1hCjVhvVF6ZTmkIb4FICVwh9W2IlWkqhcPAtcIzisIXlPUud2eXN7PNKW7SF7Eu86vDUH4-dssxvsUUlirRrMoW4vmQWXevWFNILA89K-7vMpgMnmg0RKbe_pBii5QTaRlpxjY6_vlq3vKgpAO2LYkUCvlgtKRd5bf7vPIstMTYfybyld1eBMEDV5_CIEskZvqHSBHsISzoPJbEyk5NF7sLb85ntnCM3RQ1FzdsDEbOHiCTv5bsKuLCjyume5D_VSE7KZsbvx45ycqBmyiU2INqh5kj-kF3SD71pi38HvcZSE5ZrmaIZFA1_QZjewk60Xzm47muFYJre33_e7je75ep-s394_PRhs86eHD9tpFAXa7Z8vN1kT_vs0371fHefktlh7EscOf5q9_kh-0Lf5Ta9fXimbTq03i4_bkbXffbvA6meDt37E88vwKYjC_c_HluagPKit9WXuf7M6m6pjkffGN9v-K4Xu8yFZXsGakqSMO96M06y0Jo2aCbq7mS7qxLfwU72DSnK2xftwqRM_HLhL_iE96buVPIPihOKKZsxb9IrmfzxFTDk1LQI_TAMJnWCPM7jxTzHIPDDhR_Enh3_eeUF83LuxdFE8hylTpxwRbK2eBph09oJ08nfIxAJkaGHXsxfBLEbF16wKJBF86rMq9J3ghk2XEjXxnE7dZioZAhJpdRklEIbfTVyrcWhRRwAE0IjjMRk7NXrjfX-Xh0HY6C0GkCHKTxTu1PH_BwRGs7dzXqYTzYZOCQDgR_WBdE5>53554</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            linker crashed after applying patch "[llvm] Use = default (NFC)"
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

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

    <tr>
      <th>Reporter</th>
      <td>
          Weiwei-2021
      </td>
    </tr>
</table>

<pre>
    After applying this commit: https://github.com/llvm/llvm-project/commit/152d61a821da76a4fa4532ea648b2ce11bc9a06e, my local llvm Debug build crashed at linking stage and got the follwoing error (maybe different constructors but all are undefined reference error):

**llvm/include/llvm/Support/GenericDomTreeConstruction.h:1541: undefined reference to `llvm::DominatorTreeBase<llvm::MachineBasicBlock, true>::DominatorTreeBase()'**

If it is a Release version, the building is fine. 

This patch changed the default constructor. Not sure whether it expose a problem in linker.  The build command I useds is:
` cmake -G Ninja ../llvm -DLLVM_ENABLE_PROJECTS=mlir -DLLVM_TARGETS_TO_BUILD="X86;NVPTX;AMDGPU" -DCMAKE_BUILD_TYPE=Debug
`
` cmake --build .
`
My ld version is 2.30, and cmake version is cmake version 3.18.2. Any clue about this issue or how to fix it? Thanks. 
</pre>
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