gcc/testsuite/g++.dg/cpp0x/constexpr-cast.C

   1 // Test to verify that evaluating reinterpret_cast is diagnosed in
   2 // constant expressions.
   3 // { dg-do compile { target c++11 } }
   4
   5 int i;
   6
   7 // The following was accepted due to bug 49171.
   8 constexpr void *q = reinterpret_cast<void*>(&i);    // { dg-error "not a constant expression" }
   9
  10 constexpr void *r0 = reinterpret_cast<void*>(1);    // { dg-error "not a constant expression|'reinterpret_cast' from integer to pointer" }
  11 constexpr void *r1 = reinterpret_cast<void*>(sizeof 'x');  // { dg-error "'reinterpret_cast<void\\*>\\(1\[ul\]\*\\)' is not a constant expression" }
  12
  13 template <class T>
  14 constexpr bool f ()
  15 {
  16 #if __cplusplus > 201103L
  17   T *p = reinterpret_cast<T*>(sizeof (T));  // { dg-error "not a constant expression" "" { target c++14 } }
  18   return p;
  19 #else
  20   return *reinterpret_cast<T*>(sizeof (T));  // { dg-error "not a constant expression" "" { target c++11_only } }
  21 #endif
  22 }
  23
  24 constexpr bool b = f<int>();   // { dg-message "in .constexpr. expansion of " }