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    <head>
      <base href="http://llvm.org/bugs/" />
    </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 --- - [-cxx-abi microsoft] bad layout involving empty struct field and empty virtual bases"
   href="http://llvm.org/bugs/show_bug.cgi?id=18434">18434</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>[-cxx-abi microsoft] bad layout involving empty struct field and empty virtual bases
          </td>
        </tr>

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

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

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

        <tr>
          <th>Reporter</th>
          <td>david.majnemer@gmail.com
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>llvmbugs@cs.uiuc.edu
          </td>
        </tr>

        <tr>
          <th>Classification</th>
          <td>Unclassified
          </td>
        </tr></table>
      <p>
        <div>
        <pre>given:
#if defined(__clang__) || defined(__GNUC__)
typedef __SIZE_TYPE__ size_t;
#endif
extern "C" int printf(const char *fmt, ...);
static char buffer[419430400];
inline void *operator new(size_t, void *pv) { return pv; }
struct A {
  char Field;
  A() { printf("Field: %d\n", (int)&Field - (int)buffer); }                     
};
struct B {};
struct C : A {};
struct D : virtual C {
  struct {} DField;
};
struct E : virtual D, virtual B, virtual A {};

int main() { new (buffer) E; }

MSVC gives:
Field: 4
Field: 16

clang gives:
Field: 4
Field: 20</pre>
        </div>
      </p>
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