ceph/src/boost/libs/config/test/helper_macro_test.cpp

   1 //  (C) Copyright John Maddock 2014-9.
   2 //  (C) Copyright Andrey Semashev 2017.
   3 //  Use, modification and distribution are subject to the
   4 //  Boost Software License, Version 1.0. (See accompanying file
   5 //  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   6
   7 #include <boost/config.hpp>
   8
   9 int test_fallthrough(int n)
  10 {
  11    switch (n)
  12    {
  13    case 0:
  14       n++;
  15       BOOST_FALLTHROUGH;
  16    case 1:
  17       n++;
  18       break;
  19    }
  20    return n;
  21 }
  22
  23 int test_unreachable(int i)
  24 {
  25    if(BOOST_LIKELY(i)) return i;
  26
  27    throw i;
  28    BOOST_UNREACHABLE_RETURN(0)  // NOTE: no semicolon afterwards!!
  29 }
  30
  31 BOOST_FORCEINLINE int always_inline(int i){ return ++i; }
  32 BOOST_NOINLINE int never_inline(int i){ return ++i; }
  33
  34 BOOST_NORETURN void always_throw()
  35 {
  36    throw 0;
  37 }
  38
  39 struct BOOST_MAY_ALIAS aliasing_struct {};
  40 typedef unsigned int BOOST_MAY_ALIAS aliasing_uint;
  41
  42 struct BOOST_ATTRIBUTE_NODISCARD nodiscard_struct {};
  43
  44
  45 #define test_fallthrough(x) foobar(x)
  46
  47 struct empty {};
  48 struct no_unique
  49 {
  50    int a;
  51    BOOST_ATTRIBUTE_NO_UNIQUE_ADDRESS empty b;
  52 };
  53
  54 template <bool b>
  55 struct trait
  56 {
  57    enum { value = b };
  58 };
  59
  60
  61 int main()
  62 {
  63    typedef int unused_type BOOST_ATTRIBUTE_UNUSED;
  64    try
  65    {
  66       int result = test_fallthrough BOOST_PREVENT_MACRO_SUBSTITUTION(0);
  67       BOOST_STATIC_CONSTANT(bool, value = 0);
  68       result += test_unreachable(1);
  69       result += always_inline(2);
  70       result += never_inline(3);
  71       if(BOOST_UNLIKELY(!result))
  72          always_throw();
  73       nodiscard_struct s;
  74       no_unique no_un;
  75
  76       BOOST_IF_CONSTEXPR(trait<true>::value)
  77       {
  78          result += 2;
  79       }
  80    }
  81    catch(int)
  82    {
  83       return 1;
  84    }
  85    return 0;
  86 }
  87