libcxxabi/test/catch_reference_nullptr.pass.cpp

   1 //===----------------------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 // UNSUPPORTED: c++03
  10 // UNSUPPORTED: no-exceptions
  11
  12 #include <cassert>
  13 #include <cstddef>
  14 #include <cstdlib>
  15 #include <type_traits>
  16
  17 struct A {};
  18
  19 template<typename T, bool CanCatchNullptr>
  20 static void catch_nullptr_test() {
  21   try {
  22     throw nullptr;
  23   } catch (T &p) {
  24     assert(CanCatchNullptr && !static_cast<bool>(p));
  25   } catch (...) {
  26     assert(!CanCatchNullptr);
  27   }
  28 }
  29
  30 int main(int, char**)
  31 {
  32   static_assert(std::is_same<std::nullptr_t, decltype(nullptr)>::value, "");
  33
  34   // A reference to nullptr_t can catch nullptr.
  35   catch_nullptr_test<std::nullptr_t, true>();
  36   catch_nullptr_test<const std::nullptr_t, true>();
  37   catch_nullptr_test<volatile std::nullptr_t, true>();
  38   catch_nullptr_test<const volatile std::nullptr_t, true>();
  39
  40   // No other reference type can.
  41 #if 0
  42   // FIXME: These tests fail, because the ABI provides no way for us to
  43   // distinguish this from catching by value.
  44   catch_nullptr_test<void *, false>();
  45   catch_nullptr_test<void * const, false>();
  46   catch_nullptr_test<int *, false>();
  47   catch_nullptr_test<A *, false>();
  48   catch_nullptr_test<int A::*, false>();
  49   catch_nullptr_test<int (A::*)(), false>();
  50 #endif
  51
  52   return 0;
  53 }