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      <base href="https://bugs.llvm.org/">
    </head>
    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - extern_weak creates invalid data"
   href="https://bugs.llvm.org/show_bug.cgi?id=38976">38976</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>extern_weak creates invalid data
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>lld
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>unspecified
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>PC
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>Windows NT
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>enhancement
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>P
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>COFF
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>unassignedbugs@nondot.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>ck@remobjects.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>llvm-bugs@lists.llvm.org
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Created <span class=""><a href="attachment.cgi?id=20885" name="attach_20885" title="t.il">attachment 20885</a> <a href="attachment.cgi?id=20885&action=edit" title="t.il">[details]</a></span>
t.il

An extern_weak method that's *not* resolved ends up as a as a non 0 value once
linked with lld (it becomes IMAGEBASE + 80000000):

testcase:

target triple = "x86_64-pc-windows-msvc"

declare extern_weak i8 @__elements_dll_main(i8*, i32, i8*)

define x86_stdcallcc i8 @_DllMainCRTStartup(i8*, i32, i8*) {
BasicBlock256:
  %csLoc0 = alloca i8 (i8*, i32, i8*)*
  store i8 (i8*, i32, i8*)* @__elements_dll_main, i8 (i8*, i32, i8*)** %csLoc0
  %a = load i8 (i8*, i32, i8*)*, i8 (i8*, i32, i8*)** %csLoc0
  %b = icmp eq i8 (i8*, i32, i8*)* %a, null
  br i1 %b, label %BasicBlock258, label %BasicBlock259

BasicBlock258:                                    ; preds = %BasicBlock256
  ret i8 1
BasicBlock259:                                     ; preds = %BasicBlock256
  %c = call i8 %a(i8* null, i32 0, i8* null)
  ret i8 %c
}

steps:

llc t.il -filetype=obj
lld -flavor link /dll t.il.obj</pre>
        </div>
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