libstdc++-v3/testsuite/20_util/function_objects/bind_front/107784.cc

   1 // { dg-do compile { target c++20 } }
   2
   3 #include <functional>
   4
   5 struct Foo
   6 {
   7   void func() {}
   8 };
   9
  10 void bar() { }
  11
  12 // PR libstdc++/107784 - QOI: sizeof( bind_front( Member-Function ) ) too big
  13 static_assert( sizeof(std::bind_front(&Foo::func)) == sizeof(&Foo::func) );
  14 static_assert( sizeof(std::bind_front(&bar)) == sizeof(&bar) );
  15
  16 // PR libstdc++/108290 - QoI: bind_front captureless lambda is too big
  17 auto empty_lambda = [](auto, auto) { return 0; };
  18
  19 struct {
  20   void operator()(int, int, int) { }
  21   template<typename T> void operator()(T, T) { }
  22 } empty_class;
  23
  24 static_assert(sizeof(std::bind_front(empty_lambda)) == 1);
  25 static_assert(sizeof(std::bind_front(empty_lambda, 1)) == sizeof(int));
  26 static_assert(sizeof(std::bind_front(empty_lambda, empty_lambda)) == 2);
  27 static_assert(sizeof(std::bind_front(empty_lambda, empty_class)) == 1);
  28 static_assert(sizeof(std::bind_front(empty_lambda, 1, 2)) == 2 * sizeof(int));
  29 static_assert(sizeof(std::bind_front(empty_lambda, '1', empty_lambda)) == 2);
  30 static_assert(sizeof(std::bind_front(empty_lambda, '1', empty_class)) == 1);
  31
  32 static_assert(sizeof(std::bind_front(empty_class)) == 1);
  33 static_assert(sizeof(std::bind_front(empty_class, 1)) == sizeof(int));
  34 static_assert(sizeof(std::bind_front(empty_class, empty_lambda)) == 1);
  35 static_assert(sizeof(std::bind_front(empty_class, empty_class)) == 2);
  36 static_assert(sizeof(std::bind_front(empty_class, 1, 2)) == 2 * sizeof(int));
  37 static_assert(sizeof(std::bind_front(empty_class, '1', empty_lambda)) == 1);
  38 static_assert(sizeof(std::bind_front(empty_class, '1', empty_class)) == 2);
  39
  40 struct derived1 : decltype(std::bind_front(empty_class))
  41 {
  42   int i;
  43 };
  44 static_assert(sizeof(derived1) == sizeof(int));
  45
  46 struct derived2 : decltype(std::bind_front(empty_class, empty_lambda))
  47 {
  48   int i;
  49 };
  50 static_assert(sizeof(derived2) == sizeof(int));