This is an unofficial snapshot of the ISO/IEC JTC1 SC22 WG21 Core Issues List revision 115d. See http://www.open-std.org/jtc1/sc22/wg21/ for the official list.

2024-10-26

1295. Binding a reference to an rvalue bit-field

[Voted into the WP at the February, 2012 meeting; moved to DR at the October, 2012 meeting.]

Consider the following example:

  struct X {
    unsigned bitfield : 4;
  };
  int main() {
    X x = { 1 };
    unsigned const &ref = static_cast<X &&>(x).bitfield;
  }

According to 9.4.4 [dcl.init.ref] paragraph 5, ref is bound to the bit-field xvalue.

Proposed resolution (August, 2011):

Change the indicated sub-bullet of 9.4.4 [dcl.init.ref] paragraph 5 as follows:

• is an xvalue (but is not a bit-field), class prvalue, array prvalue or function lvalue and “cv1 T1” is reference-compatible with “cv2 T2”, or