clang/test/CXX/expr/expr.prim/expr.prim.lambda/default-arguments.cpp

   1 // RUN: %clang_cc1 -fsyntax-only -std=c++11 %s -verify
   2 // RUN: %clang_cc1 -fsyntax-only -std=c++11 %s -verify -triple i386-windows
   3
   4 void defargs() {
   5   auto l1 = [](int i, int j = 17, int k = 18) { return i + j + k; };
   6   int i1 = l1(1);
   7   int i2 = l1(1, 2);
   8   int i3 = l1(1, 2, 3);
   9 }
  10
  11
  12 void defargs_errors() {
  13   auto l1 = [](int i,
  14                int j = 17,
  15                int k) { }; // expected-error{{missing default argument on parameter 'k'}}
  16
  17   auto l2 = [](int i, int j = i) {}; // expected-error{{default argument references parameter 'i'}}
  18
  19   int foo;
  20   auto l3 = [](int i = foo) {}; // expected-error{{default argument references local variable 'foo' of enclosing function}}
  21 }
  22
  23 struct NonPOD {
  24   NonPOD();
  25   NonPOD(const NonPOD&);
  26   ~NonPOD();
  27 };
  28
  29 struct NoDefaultCtor {
  30   NoDefaultCtor(const NoDefaultCtor&); // expected-note{{candidate constructor}} \
  31                                        // expected-note{{candidate constructor not viable: requires 1 argument, but 0 were provided}}
  32   ~NoDefaultCtor();
  33 };
  34
  35 template<typename T>
  36 void defargs_in_template_unused(T t) {
  37   auto l1 = [](const T& value = T()) { };  // expected-error{{no matching constructor for initialization of 'NoDefaultCtor'}} \
  38                                            // expected-note {{in instantiation of default function argument expression for 'operator()<NoDefaultCtor>' required here}}
  39   l1(t);
  40 }
  41
  42 template void defargs_in_template_unused(NonPOD);
  43 template void defargs_in_template_unused(NoDefaultCtor);  // expected-note{{in instantiation of function template specialization 'defargs_in_template_unused<NoDefaultCtor>' requested here}}
  44
  45 template<typename T>
  46 void defargs_in_template_used() {
  47   auto l1 = [](const T& value = T()) { }; // expected-error{{no matching constructor for initialization of 'NoDefaultCtor'}} \
  48                                           // expected-note {{in instantiation of default function argument expression for 'operator()<NoDefaultCtor>' required here}}
  49   l1();
  50 }
  51
  52 template void defargs_in_template_used<NonPOD>();
  53 template void defargs_in_template_used<NoDefaultCtor>(); // expected-note{{in instantiation of function template specialization}}
  54