<html>
    <head>
      <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 - unable to use variable assignment in integrated assembler"
   href="https://bugs.llvm.org/show_bug.cgi?id=37425">37425</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>unable to use variable assignment in integrated assembler
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>clang
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>trunk
          </td>
        </tr>

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

        <tr>
          <th>OS</th>
          <td>Linux
          </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>-New Bugs
          </td>
        </tr>

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

        <tr>
          <th>Reporter</th>
          <td>ndesaulniers@google.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>isanbard@gmail.com, jyknight@google.com, llvm-bugs@lists.llvm.org, niravd@google.com, pirama@google.com, srhines@google.com
          </td>
        </tr>

        <tr>
          <th>Blocks</th>
          <td>4068
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Created <span class=""><a href="attachment.cgi?id=20296" name="attach_20296" title="test.S">attachment 20296</a> <a href="attachment.cgi?id=20296&action=edit" title="test.S">[details]</a></span>
test.S

$ cat test.S 
var_xdata = %rcx

xorq var_xdata, var_xdata

$ gcc -c test.S
$ objdump -D test.o

test.o:     file format elf64-x86-64


Disassembly of section .text:

0000000000000000 <.text>:
   0:   48 31 c9                xor    %rcx,%rcx


$ clang -c test.S  
test.S:1:13: error: unknown token in expression
var_xdata = %rcx
            ^
test.S:1:13: error: missing expression
var_xdata = %rcx
            ^
test.S:3:17: error: invalid operand for instruction
xorq var_xdata, var_xdata
^

This is visible while trying to use llvm's integrated assembler to assemble the
linux kernel, particularly:

arch/x86/crypto/aes_ctrby8_avx-x86_64.S
arch/x86/crypto/aesni-intel_avx-x86_64.S</pre>
        </div>
      </p>

        <div id="referenced">
          <hr style="border: 1px dashed #969696">
          <b>Referenced Bugs:</b>
          <ul>
              <li>
                [<a class="bz_bug_link 
          bz_status_ASSIGNED "
   title="ASSIGNED - [Meta] Compiling the Linux kernel with clang"
   href="https://bugs.llvm.org/show_bug.cgi?id=4068">Bug 4068</a>] [Meta] Compiling the Linux kernel with clang
              </li>
          </ul>
        </div>
        <br>

      <hr>
      <span>You are receiving this mail because:</span>

      <ul>
          <li>You are on the CC list for the bug.</li>
      </ul>
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