clang/test/CXX/expr/expr.prim/expr.prim.lambda/p5.cpp

   1 // RUN: %clang_cc1 -std=c++11 %s -Winvalid-noreturn -verify
   2
   3 // An attribute-specifier-seq in a lambda-declarator appertains to the
   4 // type of the corresponding function call operator.
   5 void test_attributes() {
   6   auto nrl = [](int x) -> int { if (x > 0) return x; }; // expected-warning{{on-void lambda does not return a value in all control paths}}
   7
   8   // FIXME: GCC accepts the [[gnu::noreturn]] attribute here.
   9   auto nrl2 = []() [[gnu::noreturn]] { return; }; // expected-warning{{attribute 'noreturn' ignored}}
  10 }
  11
  12 template<typename T>
  13 struct bogus_override_if_virtual : public T {
  14   bogus_override_if_virtual() : T(*(T*)0) { } // expected-warning {{binding dereferenced null pointer to reference has undefined behavior}}
  15   int operator()() const;
  16 };
  17
  18 void test_quals() {
  19   // This function call operator is declared const (9.3.1) if and only
  20   // if the lambda- expression's parameter-declaration-clause is not
  21   // followed by mutable.
  22   auto l = [=](){}; // expected-note{{method is not marked volatile}}
  23   const decltype(l) lc = l;
  24   l();
  25   lc();
  26
  27   auto ml = [=]() mutable{}; // expected-note{{method is not marked const}} \
  28                              // expected-note{{method is not marked volatile}}
  29   const decltype(ml) mlc = ml;
  30   ml();
  31   mlc(); // expected-error{{no matching function for call to object of type}}
  32
  33   // It is neither virtual nor declared volatile.
  34   volatile decltype(l) lv = l;
  35   volatile decltype(ml) mlv = ml;
  36   lv(); // expected-error{{no matching function for call to object of type}}
  37   mlv(); // expected-error{{no matching function for call to object of type}}
  38
  39   bogus_override_if_virtual<decltype(l)> bogus; // expected-note{{in instantiation of member function 'bogus_override_if_virtual<(lambda}}
  40 }
  41
  42 // Core issue 974: default arguments (8.3.6) may be specified in the
  43 // parameter-declaration-clause of a lambda-declarator.
  44 int test_default_args() {
  45   return [](int i = 5, int j = 17) { return i+j;}(5, 6);
  46 }
  47
  48 // Any exception-specification specified on a lambda-expression
  49 // applies to the corresponding function call operator.
  50 void test_exception_spec() {
  51   auto tl1 = []() throw(int) {};
  52   auto tl2 = []() {};
  53   static_assert(!noexcept(tl1()), "lambda can throw");
  54   static_assert(!noexcept(tl2()), "lambda can throw");
  55
  56   auto ntl1 = []() throw() {};
  57   auto ntl2 = []() noexcept(true) {};
  58   auto ntl3 = []() noexcept {};
  59   static_assert(noexcept(ntl1()), "lambda cannot throw");
  60   static_assert(noexcept(ntl2()), "lambda cannot throw");
  61   static_assert(noexcept(ntl3()), "lambda cannot throw");
  62 }
  63