clang/test/CXX/expr/expr.post/expr.static.cast/p3-p4-0x.cpp

   1 // RUN: %clang_cc1 -std=c++11 -fsyntax-only -verify %s
   2
   3
   4 // p3
   5 // A glvalue of type "cv1 T1" can be cast to type "rvalue reference to
   6 // cv2 T2" if "cv2 T2" is reference-compatible with "cv1 T1" (8.5.3).
   7 // p4
   8 // Otherwise, an expression e can be explicitly converted to a type T using a
   9 // static_cast of the form static_cast<T>(e) if the declaration T t(e); is
  10 // well-formed, for some invented temporary variable t (8.5). [...]
  11 struct A { };
  12 struct B : A { };
  13
  14 struct C { explicit operator A&&(); };
  15 struct D { operator B(); };
  16
  17 template<typename T> T& lvalue();
  18 template<typename T> T&& xvalue();
  19 template <typename T> T prvalue();
  20
  21 void test(A &a, B &b) {
  22   A &&ar0 = static_cast<A&&>(prvalue<A>());
  23   A &&ar1 = static_cast<A&&>(prvalue<B>());
  24   A &&ar2 = static_cast<A&&>(lvalue<C>());
  25   A &&ar3 = static_cast<A&&>(xvalue<C>());
  26   A &&ar4 = static_cast<A&&>(prvalue<C>());
  27   A &&ar5 = static_cast<A&&>(lvalue<D>());
  28   A &&ar6 = static_cast<A&&>(xvalue<D>());
  29   A &&ar7 = static_cast<A&&>(prvalue<D>());
  30
  31   A &&ar8 = static_cast<A&&>(prvalue<const A>()); // expected-error {{binding reference of type 'A' to value of type 'const A' drops 'const' qualifier}}
  32   A &&ar9 = static_cast<A&&>(lvalue<const A>());  // expected-error {{cannot cast from lvalue of type 'const A'}}
  33   A &&ar10 = static_cast<A&&>(xvalue<const A>()); // expected-error {{cannot cast from rvalue of type 'const A'}}
  34
  35   const A &&ar11 = static_cast<const A&&>(prvalue<A>());
  36   const A &&ar12 = static_cast<const A&&>(prvalue<B>());
  37   const A &&ar13 = static_cast<const A&&>(lvalue<C>());
  38   const A &&ar14 = static_cast<const A&&>(xvalue<C>());
  39   const A &&ar15 = static_cast<const A&&>(prvalue<C>());
  40   const A &&ar16 = static_cast<const A&&>(lvalue<D>());
  41
  42   const A &&ar17 = static_cast<const A&&>(prvalue<A const volatile>()); // expected-error {{binding reference of type 'const A' to value of type 'const volatile A' drops 'volatile' qualifier}}
  43 }