clang/test/Sema/stmt-expr-in-default-arg.cpp

   1 // RUN: %clang_cc1 %s -fsyntax-only -verify -std=c++20
   2
   3 void foo() {
   4   void fn(int i, int = ({ 1; })); // expected-error {{default argument may not use a GNU statement expression}}
   5
   6   auto a = [](int = ({ 1; })) {}; // expected-error {{default argument may not use a GNU statement expression}}
   7
   8   auto b = []<int = ({ 1; })>(){}; // expected-error {{default non-type template argument may not use a GNU statement expression}}
   9
  10   void fn(int i, int j = ({{}, {}, {,}}), int k = ""); // expected-error {{default argument may not use a GNU statement expression}} expected-error {{cannot initialize a parameter of type 'int' with an lvalue of type 'const char[1]'}} expected-note {{passing argument to parameter 'k' here}}
  11 }
  12
  13 template <int foo = ({ 1; })> // expected-error {{default non-type template argument may not use a GNU statement expression}}
  14 void f() {}
  15
  16 template <int bar = ({ 1; })> // expected-error {{default non-type template argument may not use a GNU statement expression}}
  17 class S {};
  18
  19 template <typename Callable>
  20 int bar(Callable &&Call) {
  21   return Call();
  22 }
  23
  24 int baz() {
  25   auto l = [](int a = ({ int x = 12; x; })) { // expected-error {{default argument may not use a GNU statement expression}}
  26     return 1;
  27   };
  28   return bar(l);
  29 }