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    <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 - Static constexpr string struct causes unresolved symbols on Windows"
   href="https://bugs.llvm.org/show_bug.cgi?id=43280">43280</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>Static constexpr string struct causes unresolved symbols on Windows
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>new-bugs
          </td>
        </tr>

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

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

        <tr>
          <th>OS</th>
          <td>All
          </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>unassignedbugs@nondot.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>ToHe_EMA@gmx.de
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>htmldeveloper@gmail.com, llvm-bugs@lists.llvm.org
          </td>
        </tr></table>
      <p>
        <div>
        <pre>We are currently exploring to compile our software on Windows with Clang, but
hit a couple Clang/LLVM bugs along the way. Using a static constexpr string in
a struct/class results in unresolved symbols when linking. The minimal code
needed to trigger the bug looks like this:
struct Struct
{
        static constexpr char const* ConstexprVar = "Test";
        char const* const* Do() { return &ConstexprVar; }
};
int main() { Struct().Do(); }

It is simply compiled with "clang++ Main.cpp" without further options which
then results in this error:
<span class="quote">>Main-70a406.o : error LNK2019: unresolved external symbol "public: static char const * const Struct::ConstexprVar" >(?ConstexprVar@Struct@@2QEBDEB) referenced in
> function "public: char const * const * __cdecl Struct::Do(void)" (?Do@Struct@@QEAAPEBQEBDXZ)
>Main.o : fatal error LNK1120: 1 unresolved externals
>clang++: error: linker command failed with exit code 1120 (use -v to see invocation)</span >

When trying to link with lld, the result is the same:
<span class="quote">>lld: error: undefined symbol: public: static char const *const Struct::ConstexprVar
>>> referenced by Main.o:(public: char const *const * __cdecl Struct::Do(void))</span >

At least the current stable release 8.0 and the nightly build (from here
<a href="https://llvm.org/builds/">https://llvm.org/builds/</a>) are affected.</pre>
        </div>
      </p>


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