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    <head>
      <base href="https://llvm.org/bugs/" />
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    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW --- - Error with C++11 uniform initialization of an array of type with explicit default constructor"
   href="https://llvm.org/bugs/show_bug.cgi?id=27052">27052</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>Error with C++11 uniform initialization of an array of type with explicit default constructor
          </td>
        </tr>

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

        <tr>
          <th>Version</th>
          <td>3.7
          </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>normal
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>P
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>C++11
          </td>
        </tr>

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

        <tr>
          <th>Reporter</th>
          <td>mosra@centrum.cz
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>dgregor@apple.com, llvm-bugs@lists.llvm.org
          </td>
        </tr>

        <tr>
          <th>Classification</th>
          <td>Unclassified
          </td>
        </tr></table>
      <p>
        <div>
        <pre>I am getting an error when compiling the following snippet:

    struct Explicit {
        explicit Explicit() {}
    };

    struct A {
        A(): _a{} {}

        Explicit _a[5];
    };

    int main() {}

Clang 3.7.1 complains that `error: chosen constructor is explicit in
copy-initialization`, both GCC 5.3 and MSVC 2015 compile fine. The behavior
differs when I make the following changes:

- If I remove the `explicit` keyword, it compiles fine (of course).
- If I make the `_a` member a non-array, it compiles fine.
- If I change `_a{}` to the C++03-style `_a()`, it compiles fine.
- If I change `_a{}` to `_a{Explicit{}, Explicit{}, Explicit{}, Explicit{},
Explicit{}}`, it compiles fine.
- If I change the constructor to `explicit Explicit() = default;`, it compiles
fine.

The problem is not just when using constructor initializer lists, but also when
initializing the array as a variable like this:

    Explicit b[5]{};

This behavior seems rather arbitrary to me and since the "old" C++03-style
works okay, I think it should have the same behavior in C++11.

This probably affects also older versions, didn't have a chance to test.</pre>
        </div>
      </p>
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