<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/72854>72854</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            fix python SyntaxWarnings (invalid escape sequence) in check-all output
        </td>
    </tr>

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

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

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

<pre>
    Such as:

```
src_dir/clang/lib/Tooling/DumpTool/generate_cxx_src_locs.py:28: SyntaxWarning: invalid escape sequence '\*'    self.implementationContent += """
src_dir/llvm/utils/lit/lit/TestRunner.py:205: SyntaxWarning: invalid escape sequence '\c' """
src_dir/llvm/utils/lit/lit/TestRunner.py:1561: SyntaxWarning: invalid escape sequence '\s'                     match = _caching_re_compile("^\s*%else\s*(%{)?").search(ln)
src_dir/libcxx/utils/libcxx/test/format.py:64: SyntaxWarning: invalid escape sequence '\s'                     for output in re.split('[$]\s*":"\s*"RUN: at line \d+"', fullOutput):
src_dir/libcxx/utils/libcxx/test/params.py:121: SyntaxWarning: invalid escape sequence '\+' AddSubstitution("%{cxx_std}", re.sub("\+", "x", std)),
src_dir/libcxx/utils/libcxx/test/params.py:214: SyntaxWarning: invalid escape sequence '\+' AddFeature("stdlib=libc++") if re.match(".+-libc\+\+", stdlib) else None,
src_dir/compiler-rt/test/lit.common.cfg.py:800: SyntaxWarning: invalid escape sequence '\$'                    "-Wl,-z,origin -Wl,-rpath,\$ORIGIN -L%T -l%xdynamiclib_namespec"
src_dir/compiler-rt/test/lit.common.cfg.py:809: SyntaxWarning: invalid escape sequence '\$' "-Wl,-rpath,\$ORIGIN -L%T -l%xdynamiclib_namespec" + postfix,
src_dir/compiler-rt/test/lit.common.cfg.py:817: SyntaxWarning: invalid escape sequence '\$'                    "-Wl,-R\$ORIGIN -L%T -l%xdynamiclib_namespec" + postfix,
src_dir/llvm/test/lit.cfg.py:275: SyntaxWarning: invalid escape sequence '\d' match = re.search("release (\d+)\.(\d+)", ptxas_out)
```

Converting to raw strings addresses the issue.

Thanks a lot @ldionne for pointing me to the right direction, on properly re-submitting this pull request.

cc: @petrhosek

/branch eleftg/llvm-project/python_SyntaxWarnings_backport_17
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJy0ls-PmzgUx_8a52IFwQMGOOSQIZtVpVUrTWfVY2TMC3jH2Kxt2mT_-pUNmTTd9tB0NkIotvDz9_N-2cxa0SnEDckfSb5bscn12mxQ4tF1q0a3583HifeUWZJuSbwj8eX9EC9PGFrDD60wBPZcMtUR2EvRENg_ay1FGO-mYfQjAvsOFRrm8MBPp4NfKTW30Xgm6RZKkm7px7Ny7PSJGeXXplsq1GcmRUvRcjYitfj3hIojJVCQvCawJVBQSqlFeYzEMEocUDnmhFa1Vg6VowQeSbqjBGB5vtEt5eeBwH5yQtog372-n9G6p0kpNIvIOL9DJfca32L7JH9I7tjfLj76z29gjvfUO-fAGe-F6g4GD1wPo5BIoPRq899mC1sCOUqLr6OSQE6KRwIVSfcBrYosMsN7AqVUfv5bUtHw0-mGdZlwaD3vUZuBuZn1IXtL0qM2VE9unBwVihqM7BhcXIZ1jwQyku9e0cCnvGe_jJ_-fO83Z45KoZCSvG59VnnogkBNj5OUH4L54I7tT5OPzLBhqYQE7gly0FPQbdt-nBrrhJt8DSxBDJEKNedaUuzCVB3cMDWXONcXotrn6mn56xdAFZ76l6gguSegV6o9MjeZJSuta32XSXd-x_DNLL2i4uixQmLPn0YEHtfhs9na15yLGaioz2z6Xiv8DuZSD2Zt3BVNChdxPQxaRfzYzYhlHN-FmP0gawnA-pMkUK__IVBrIzqh6DJjRuZ6LzYY-PD07vd37-n6DwL5M11LAvmpPSs2CC5Fc1BsQDsi_073-Qm46n64K8m9un0Xp6O27ihOvxSjpPifYvT0xkjLufA1ywUCinuOodYjXFu-r_5LuyYABiUy678tX9tbRfI6up2YC2d0J2YPem5337sVzO9aq89onFAddZoa9oVaZ4TqLGVta9BatNT1SIW1E0Zfr3zumXqxlFGpHSVZLFuhlcLQx0ctVLA5oDfrDRjR9Y62wiCfu15NtaKj0SMaeaYG13ZqBuFmKb2wdJykpMY7yLqbnTn3niRZPKIzvbb4cnP5gX1jmOI9nS9KS5zWo9F_IQ897-x6rQ43sbGHhvGXURt3SIpVu0nbKq3YCjdJEcdZGT_kyarf5E3-0GIaV1Aig7ho4zLmcVImLMWqhGolNhBDmiQQJ0mWJUl0TDGGOIMyy5LymGcki3FgQkZeU6RNtwqe3RRQ5tlKsgalDfc9AIVfZreH3r9bmU3gaKbOencL6-zVihNO4uYoTnSmu80863PmB6kXWrKivEf-smZSLofwajJy0zs3hssl7P3VULh-any9XnP_G9cGvf6cCTz_BgAA__-YIk-0">