<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 - clang-cl emits bogus error LNK2019: unresolved external symbol _wmemchr"
   href="https://bugs.llvm.org/show_bug.cgi?id=37911">37911</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>clang-cl emits bogus error LNK2019: unresolved external symbol _wmemchr
          </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>Windows NT
          </td>
        </tr>

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

        <tr>
          <th>Severity</th>
          <td>normal
          </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>sfinae@hotmail.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>llvm-bugs@lists.llvm.org
          </td>
        </tr></table>
      <p>
        <div>
        <pre>This was reported to MSVC:
<a href="https://developercommunity.visualstudio.com/content/problem/234075/unresolved-symbols-in-iosfwd-with-has-constexpr-ch-1.html">https://developercommunity.visualstudio.com/content/problem/234075/unresolved-symbols-in-iosfwd-with-has-constexpr-ch-1.html</a>

It appears to be a Clang bug.

C:\Temp\CLANG_REPRO>clang-cl -m32 -v
clang version 6.0.0 (tags/RELEASE_600/final)
Target: i386-pc-windows-msvc
Thread model: posix
InstalledDir: S:\msvc\src\vctools\NonShip\ClangLLVM\bin

C:\Temp\CLANG_REPRO>type pch.h
#pragma once
#include <string>

C:\Temp\CLANG_REPRO>type pch.cpp
// empty file

C:\Temp\CLANG_REPRO>type test.cpp
int main() {
    (void) std::wstring().find(L' ', 0);
}

C:\Temp\CLANG_REPRO>clang-cl -m32 /EHsc /nologo /W4 -Ycpch.h -FI pch.h pch.cpp
-c -std:c++latest -MDd

C:\Temp\CLANG_REPRO>clang-cl -m32 /EHsc /nologo /W4 -Yupch.h -FI pch.h test.cpp
pch.obj -std:c++latest -MDd
test-c47dea.obj : error LNK2019: unresolved external symbol _wmemchr referenced
in function "public: static wchar_t const * __cdecl
std::_WChar_traits<wchar_t>::find(wchar_t const *,unsigned int,wchar_t const
&)" (?find@?$_WChar_traits@_W@std@@SAPB_WPB_WIAB_W@Z)
test.exe : fatal error LNK1120: 1 unresolved externals
clang-cl.exe: error: linker command failed with exit code 1120 (use -v to see
invocation)</pre>
        </div>
      </p>


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

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