llvm-project/clang/test/CXX/drs/dr13xx.cpp

463 lines
19 KiB
C++

// RUN: %clang_cc1 -std=c++98 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
// RUN: %clang_cc1 -std=c++11 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
// RUN: %clang_cc1 -std=c++14 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
// RUN: %clang_cc1 -std=c++17 %s -verify -fexceptions -fcxx-exceptions -pedantic-errors
__extension__ typedef __SIZE_TYPE__ size_t;
namespace std {
template<typename T> struct initializer_list {
const T *ptr;
size_t n;
initializer_list(const T*, size_t);
};
}
namespace dr1310 { // dr1310: 5
struct S {} * sp = new S::S; // expected-error {{qualified reference to 'S' is a constructor name}}
void f() {
S::S(a); // expected-error {{qualified reference to 'S' is a constructor name}}
}
struct T { int n; typedef int U; typedef T V; };
int k = T().T::T::n;
T::V v;
struct U { int U; };
int u = U().U::U;
struct U::U w;
struct V : T::T {
// FIXME: This is technically ill-formed, but we consider that to be a defect.
V() : T::T() {}
};
template<typename T> struct VT : T::T {
VT() : T::T() {}
};
template struct VT<T>;
template<template<typename> class> class TT {};
template<typename> class TTy {};
template<typename T> struct WBase {};
template<typename T> struct W : WBase<T> { typedef int X; int n; };
void w_test() {
W<int>::W w1a; // expected-error {{qualified reference to 'W' is a constructor name}}
W<int>::W::X w1ax;
W<int>::W<int> w1b; // expected-error {{qualified reference to 'W' is a constructor name}}
W<int>::W<int>::X w1bx;
typename W<int>::W w2a; // expected-error {{qualified reference to 'W' is a constructor name}} expected-error 0-1{{outside of a template}}
typename W<int>::W::X w2ax; // expected-error 0-1{{outside of a template}}
typename W<int>::W<int> w2b; // expected-error {{qualified reference to 'W' is a constructor name}} expected-error 0-1{{outside of a template}}
typename W<int>::W<int>::X w2bx; // expected-error 0-1{{outside of a template}}
W<int>::template W<int> w3; // expected-error {{qualified reference to 'W' is a constructor name}} expected-error 0-1{{outside of a template}}
W<int>::template W<int>::X w3x; // expected-error 0-1{{outside of a template}}
typename W<int>::template W<int> w4; // expected-error {{qualified reference to 'W' is a constructor name}} expected-error 0-2{{outside of a template}}
typename W<int>::template W<int>::X w4x; // expected-error 0-2{{outside of a template}}
TT<W<int>::W> tt1; // expected-error {{qualified reference to 'W' is a constructor name}}
TTy<W<int>::W> tt1a; // expected-error {{qualified reference to 'W' is a constructor name}}
TT<W<int>::template W> tt2; // expected-error {{qualified reference to 'W' is a constructor name}} expected-error 0-1{{outside of a template}}
TT<W<int>::WBase> tt3;
TTy<W<int>::WBase> tt3a;
TT<W<int>::template WBase> tt4; // expected-error 0-1{{outside of a template}}
W<int> w;
(void)w.W::W::n;
(void)w.W<int>::W::n;
(void)w.W<int>::W<int>::n;
(void)w.W<int>::template W<int>::n; // expected-error 0-1{{outside of a template}}
}
template<typename W>
void wt_test() {
typename W::W w2a; // expected-error {{qualified reference to 'W' is a constructor name}}
typename W::template W<int> w4; // expected-error {{qualified reference to 'W' is a constructor name}}
TTy<typename W::W> tt2; // expected-error {{qualified reference to 'W' is a constructor name}}
TT<W::template W> tt3; // expected-error {{qualified reference to 'W' is a constructor name}}
}
template<typename W>
void wt_test_good() {
typename W::W::X w2ax;
typename W::template W<int>::X w4x;
TTy<typename W::WBase> tt4;
TT<W::template WBase> tt5;
W w;
(void)w.W::W::n;
(void)w.W::template W<int>::n;
(void)w.template W<int>::W::n;
(void)w.template W<int>::template W<int>::n;
}
template void wt_test<W<int> >(); // expected-note {{instantiation of}}
template void wt_test_good<W<int> >();
}
namespace dr1315 { // dr1315: partial
template <int I, int J> struct A {};
template <int I> // expected-note {{non-deducible template parameter 'I'}}
struct A<I + 5, I * 2> {}; // expected-error {{contains a template parameter that cannot be deduced}}
template <int I> struct A<I, I> {};
template <int I, int J, int K> struct B;
template <int I, int K> struct B<I, I * 2, K> {}; // expected-note {{matches}}
B<1, 2, 3> b1;
// Multiple declarations with the same dependent expression are equivalent
// for partial ordering purposes.
template <int I> struct B<I, I * 2, 2> { typedef int type; };
B<1, 2, 2>::type b2;
// Multiple declarations with differing dependent expressions are unordered.
template <int I, int K> struct B<I, I + 1, K> {}; // expected-note {{matches}}
B<1, 2, 4> b3; // expected-error {{ambiguous}}
// FIXME: Under dr1315, this is perhaps valid, but that is not clear: this
// fails the "more specialized than the primary template" test because the
// dependent type of T::value is not the same as 'int'.
// A core issue will be opened to decide what is supposed to happen here.
template <typename T, int I> struct C;
template <typename T> struct C<T, T::value>;
// expected-error@-1 {{type of specialized non-type template argument depends on a template parameter of the partial specialization}}
}
namespace dr1330 { // dr1330: 4 c++11
// exception-specifications are parsed in a context where the class is complete.
struct A {
void f() throw(T) {} // expected-error 0-1{{C++17}} expected-note 0-1{{noexcept}}
struct T {};
#if __cplusplus >= 201103L
void g() noexcept(&a == b) {}
static int a;
static constexpr int *b = &a;
#endif
};
void (A::*af1)() throw(A::T) = &A::f; // expected-error 0-1{{C++17}} expected-note 0-1{{noexcept}}
void (A::*af2)() throw() = &A::f; // expected-error-re {{{{not superset|different exception spec}}}}
#if __cplusplus >= 201103L
static_assert(noexcept(A().g()), "");
#endif
// Likewise, they're instantiated separately from an enclosing class template.
template<typename U>
struct B {
void f() throw(T, typename U::type) {} // expected-error 0-1{{C++17}} expected-note 0-1{{noexcept}}
struct T {};
#if __cplusplus >= 201103L
void g() noexcept(&a == b && U::value) {}
static int a;
static constexpr int *b = &a;
#endif
};
B<int> bi; // ok
struct P {
typedef int type;
static const int value = true;
};
void (B<P>::*bpf1)() throw(B<P>::T, int) = &B<P>::f; // expected-error 0-1{{C++17}} expected-note 0-1{{noexcept}}
#if __cplusplus < 201103L
// expected-error@-2 {{not superset}}
// FIXME: We only delay instantiation in C++11 onwards. In C++98, something
// weird happens: instantiation of B<P> fails because it references T before
// it's instantiated, but the diagnostic is suppressed in
// Sema::FindInstantiatedDecl because we've already hit an error. This is
// obviously a bad way to react to this situation; we should still producing
// the "T has not yet been instantiated" error here, rather than giving
// confusing errors later on.
#endif
void (B<P>::*bpf2)() throw(int) = &B<P>::f; // expected-error 0-1{{C++17}} expected-note 0-1{{noexcept}}
#if __cplusplus <= 201402L
// expected-error@-2 {{not superset}}
#else
// expected-warning@-4 {{not superset}}
#endif
void (B<P>::*bpf3)() = &B<P>::f;
void (B<P>::*bpf4)() throw() = &B<P>::f;
#if __cplusplus <= 201402L
// expected-error@-2 {{not superset}}
#else
// expected-error@-4 {{different exception specifications}}
#endif
#if __cplusplus >= 201103L
static_assert(noexcept(B<P>().g()), "");
struct Q { static const int value = false; };
static_assert(!noexcept(B<Q>().g()), "");
#endif
template<typename T> int f() throw(typename T::error) { return 0; } // expected-error 1-4{{prior to '::'}} expected-note 0-1{{prior to '::'}} expected-note 0-1{{requested here}}
#if __cplusplus > 201402L
// expected-error@-2 0-1{{C++17}} expected-note@-2 0-1{{noexcept}}
#endif
// An exception-specification is needed even if the function is only used in
// an unevaluated operand.
int f1 = sizeof(f<int>()); // expected-note {{instantiation of}}
#if __cplusplus >= 201103L
decltype(f<char>()) f2; // expected-note {{instantiation of}}
bool f3 = noexcept(f<float>()); // expected-note {{instantiation of}}
#endif
// In C++17 onwards, substituting explicit template arguments into the
// function type substitutes into the exception specification (because it's
// part of the type). In earlier languages, we don't notice there's a problem
// until we've already started to instantiate.
template int f<short>();
#if __cplusplus >= 201703L
// expected-error@-2 {{does not refer to a function template}}
#else
// expected-note@-4 {{instantiation of}}
#endif
template<typename T> struct C {
C() throw(typename T::type); // expected-error 1-2{{prior to '::'}}
#if __cplusplus > 201402L
// expected-error@-2 0-1{{C++17}} expected-note@-2 0-1{{noexcept}}
#endif
};
struct D : C<void> {}; // ok
#if __cplusplus < 201103L
// expected-note@-2 {{instantiation of}}
#endif
void f(D &d) { d = d; } // ok
struct E : C<int> {}; // expected-note {{in instantiation of}}
#if __cplusplus >= 201103L
E e; // expected-note {{needed here}}
#endif
}
namespace dr1346 { // dr1346: 3.5
auto a(1); // expected-error 0-1{{extension}}
auto b(1, 2); // expected-error {{multiple expressions}} expected-error 0-1{{extension}}
#if __cplusplus >= 201103L
auto c({}); // expected-error {{parenthesized initializer list}}
auto d({1}); // expected-error {{parenthesized initializer list}}
auto e({1, 2}); // expected-error {{parenthesized initializer list}}
#endif
template<typename...Ts> void f(Ts ...ts) { // expected-error 0-1{{extension}}
auto x(ts...); // expected-error {{empty}} expected-error 0-1{{extension}}
}
template void f(); // expected-note {{instantiation}}
#if __cplusplus >= 201103L
void init_capture() {
[a(1)] {} (); // expected-error 0-1{{extension}}
[b(1, 2)] {} (); // expected-error {{multiple expressions}} expected-error 0-1{{extension}}
#if __cplusplus >= 201103L
[c({})] {} (); // expected-error {{parenthesized initializer list}} expected-error 0-1{{extension}}
[d({1})] {} (); // expected-error {{parenthesized initializer list}} expected-error 0-1{{extension}}
[e({1, 2})] {} (); // expected-error {{parenthesized initializer list}} expected-error 0-1{{extension}}
#endif
}
#endif
}
namespace dr1347 { // dr1347: yes
auto x = 5, *y = &x; // expected-error 0-1{{extension}}
auto z = y, *q = y; // expected-error {{'auto' deduced as 'int *' in declaration of 'z' and deduced as 'int' in declaration of 'q'}} expected-error 0-1{{extension}}
#if __cplusplus >= 201103L
auto a = 5, b = {1, 2}; // expected-error {{'auto' deduced as 'int' in declaration of 'a' and deduced as 'std::initializer_list<int>' in declaration of 'b'}}
auto (*fp)(int) -> int, i = 0; // expected-error {{declaration with trailing return type must be the only declaration in its group}}
#endif
}
namespace dr1358 { // dr1358: yes
#if __cplusplus >= 201103L
struct Lit { constexpr operator int() const { return 0; } };
struct NonLit { NonLit(); operator int(); }; // expected-note 2{{no constexpr constructors}}
struct NonConstexprConv { constexpr operator int() const; };
struct Virt { virtual int f(int) const; };
template<typename T, typename U, typename V> struct A : V {
int member;
constexpr A(U u) : member(u) {}
constexpr T f(U u) const { return T(); }
};
constexpr A<Lit, Lit, Lit> ce = Lit();
constexpr int k = ce.f(Lit{});
// Can have a non-literal return type and parameter type.
// Constexpr function can be implicitly virtual.
A<NonLit, NonLit, Virt> a = NonLit();
void g() { a.f(NonLit()); }
// Constructor is still constexpr, so this is a literal type.
static_assert(__is_literal_type(decltype(a)), "");
// Constructor can call non-constexpr functions.
A<Lit, NonConstexprConv, Lit> b = NonConstexprConv();
// But the corresponding non-template cases are rejected.
struct B : Virt {
int member;
constexpr B(NonLit u) : member(u) {} // expected-error {{not a literal type}}
constexpr NonLit f(NonLit u) const { return NonLit(); } // expected-error {{not a literal type}}
};
#endif
}
namespace dr1359 { // dr1359: 3.5
#if __cplusplus >= 201103L
union A { constexpr A() = default; };
union B { constexpr B() = default; int a; }; // expected-error {{not constexpr}} expected-note 2{{candidate}}
union C { constexpr C() = default; int a, b; }; // expected-error {{not constexpr}} expected-note 2{{candidate}}
struct X { constexpr X() = default; union {}; }; // expected-error {{does not declare anything}}
struct Y { constexpr Y() = default; union { int a; }; }; // expected-error {{not constexpr}} expected-note 2{{candidate}}
constexpr A a = A();
constexpr B b = B(); // expected-error {{no matching}}
constexpr C c = C(); // expected-error {{no matching}}
constexpr X x = X();
constexpr Y y = Y(); // expected-error {{no matching}}
#endif
}
namespace dr1388 { // dr1388: 4
template<typename A, typename ...T> void f(T..., A); // expected-note 1+{{candidate}} expected-error 0-1{{C++11}}
template<typename ...T> void g(T..., int); // expected-note 1+{{candidate}} expected-error 0-1{{C++11}}
template<typename ...T, typename A> void h(T..., A); // expected-note 1+{{candidate}} expected-error 0-1{{C++11}}
void test_f() {
f(0); // ok, trailing parameter pack deduced to empty
f(0, 0); // expected-error {{no matching}}
f<int>(0);
f<int>(0, 0); // expected-error {{no matching}}
f<int, int>(0, 0);
f<int, int, int>(0, 0); // expected-error {{no matching}}
g(0);
g(0, 0); // expected-error {{no matching}}
g<>(0);
g<int>(0); // expected-error {{no matching}}
g<int>(0, 0);
h(0);
h(0, 0); // expected-error {{no matching}}
h<int>(0, 0);
h<int, int>(0, 0); // expected-error {{no matching}}
}
// A non-trailing parameter pack is still a non-deduced context, even though
// we know exactly how many arguments correspond to it.
template<typename T, typename U> struct pair {};
template<typename ...T> struct tuple { typedef char type; }; // expected-error 0-2{{C++11}}
template<typename ...T, typename ...U> void f_pair_1(pair<T, U>..., int); // expected-error 0-2{{C++11}} expected-note {{[with T = <int, long>]: deduced incomplete pack <(no value), (no value)> for template parameter 'U'}}
template<typename ...T, typename U> void f_pair_2(pair<T, char>..., U); // expected-error 0-2{{C++11}}
template<typename ...T, typename ...U> void f_pair_3(pair<T, U>..., tuple<U...>); // expected-error 0-2{{C++11}} expected-note {{deduced packs of different lengths for parameter 'U' (<(no value), (no value)> vs. <char>)}}
template<typename ...T> void f_pair_4(pair<T, char>..., T...); // expected-error 0-2{{C++11}} expected-note {{<int, long> vs. <int, long, const char *>}}
void g(pair<int, char> a, pair<long, char> b, tuple<char, char> c) {
f_pair_1<int, long>(a, b, 0); // expected-error {{no match}}
f_pair_2<int, long>(a, b, 0);
f_pair_3<int, long>(a, b, c);
f_pair_3<int, long>(a, b, tuple<char>()); // expected-error {{no match}}
f_pair_4<int, long>(a, b, 0, 0L);
f_pair_4<int, long>(a, b, 0, 0L, "foo"); // expected-error {{no match}}
}
}
namespace dr1391 { // dr1391: partial
struct A {}; struct B : A {};
template<typename T> struct C { C(int); typename T::error error; }; // expected-error 2{{'::'}}
template<typename T> struct D {};
// No deduction is performed for parameters with no deducible template-parameters, therefore types do not need to match.
template<typename T> void a(T, int T::*);
void test_a(int A::*p) { a(A(), p); } // ok, type of second parameter does not need to match
namespace dr_example_1 {
template<typename T, typename U> void f(C<T>);
template<typename T> void f(D<T>);
void g(D<int> d) {
f(d); // ok, first 'f' eliminated by deduction failure
f<int>(d); // ok, first 'f' eliminated because 'U' cannot be deduced
}
}
namespace dr_example_2 {
template<typename T> typename C<T>::error f(int, T);
template<typename T> T f(T, T);
void g(A a) {
f(a, a); // ok, no conversion from A to int for first parameter of first candidate
}
}
namespace std_example {
template<typename T> struct Z {
typedef typename T::x xx;
};
template<typename T> typename Z<T>::xx f(void *, T);
template<typename T> void f(int, T);
struct A {} a;
void g() { f(1, a); }
}
template<typename T> void b(C<int> ci, T *p);
void b(...);
void test_b() {
b(0, 0); // ok, deduction fails prior to forming a conversion sequence and instantiating C<int>
// FIXME: The "while substituting" note should point at the overload candidate.
b<int>(0, 0); // expected-note {{instantiation of}} expected-note {{while substituting}}
}
template<typename T> struct Id { typedef T type; };
template<typename T> void c(T, typename Id<C<T> >::type);
void test_c() {
// Implicit conversion sequences for dependent types are checked later.
c(0.0, 0); // expected-note {{instantiation of}}
}
namespace partial_ordering {
// FIXME: Second template should be considered more specialized because non-dependent parameter is ignored.
template<typename T> int a(T, short) = delete; // expected-error 0-1{{extension}} expected-note {{candidate}}
template<typename T> int a(T*, char); // expected-note {{candidate}}
int test_a = a((int*)0, 0); // FIXME: expected-error {{ambiguous}}
// FIXME: Second template should be considered more specialized:
// deducing #1 from #2 ignores the second P/A pair, so deduction succeeds,
// deducing #2 from #1 fails to deduce T, so deduction fails.
template<typename T> int b(T, int) = delete; // expected-error 0-1{{extension}} expected-note {{candidate}}
template<typename T, typename U> int b(T*, U); // expected-note {{candidate}}
int test_b = b((int*)0, 0); // FIXME: expected-error {{ambiguous}}
// Unintended consequences: because partial ordering does not consider
// explicit template arguments, and deduction from a non-dependent type
// vacuously succeeds, a non-dependent template is less specialized than
// anything else!
// According to DR1391, this is ambiguous!
template<typename T> int c(int);
template<typename T> int c(T);
int test_c1 = c(0); // ok
int test_c2 = c<int>(0); // FIXME: apparently ambiguous
}
}
namespace dr1399 { // dr1399: dup 1388
template<typename ...T> void f(T..., int, T...) {} // expected-note {{candidate}} expected-error 0-1{{C++11}}
void g() {
f(0);
f<int>(0, 0, 0);
f(0, 0, 0); // expected-error {{no match}}
}
}
namespace dr1307 { // dr1307: 14
#if __cplusplus >= 201103L
void f(int const (&)[2]);
void f(int const (&)[3]);
void caller() {
// This should not be ambiguous, the 2nd overload is better.
f({1, 2, 3});
}
#endif // __cplusplus >= 201103L
} // namespace dr1307