llvm-project/clang/test/SemaTemplate/default-arguments-cxx0x.cpp

88 lines
1.8 KiB
C++

// RUN: %clang_cc1 -fsyntax-only -std=c++11 -verify %s
// expected-no-diagnostics
// Test default template arguments for function templates.
template<typename T = int>
void f0();
template<typename T>
void f0();
void g0() {
f0(); // okay!
}
template<typename T, int N = T::value>
int &f1(T);
float &f1(...);
struct HasValue {
static const int value = 17;
};
void g1() {
float &fr = f1(15);
int &ir = f1(HasValue());
}
namespace PR16689 {
template <typename T1, typename T2> class tuple {
public:
template <typename = T2>
constexpr tuple() {}
};
template <class X, class... Y> struct a : public X {
using X::X;
};
auto x = a<tuple<int, int> >();
}
namespace PR16975 {
template <typename...> struct is {
constexpr operator bool() const { return false; }
};
template <typename... Types>
struct bar {
template <typename T,
bool = is<Types...>()>
bar(T);
};
struct baz : public bar<> {
using bar::bar;
};
baz data{0};
}
// rdar://23810407
// An IRGen failure due to a symbol collision due to a default argument
// being instantiated twice. Credit goes to Richard Smith for this
// reduction to a -fsyntax-only failure.
namespace rdar23810407 {
// Instantiating the default argument multiple times will produce two
// different lambda types and thus instantiate this function multiple
// times, which will produce conflicting extern variable declarations.
template<typename T> int f(T t) {
extern T rdar23810407_variable;
return 0;
}
template<typename T> int g(int a = f([] {}));
void test() {
g<int>();
g<int>();
}
}
// rdar://problem/24480205
namespace PR13986 {
constexpr unsigned Dynamic = 0;
template <unsigned> class A { template <unsigned = Dynamic> void m_fn1(); };
class Test {
~Test() {}
A<1> m_target;
};
}