llvm-project/clang/test/SemaTemplate/friend-template.cpp

332 lines
7.5 KiB
C++

// RUN: %clang_cc1 -fsyntax-only -verify %s
// PR5057
namespace test0 {
namespace std {
class X {
public:
template<typename T> friend struct Y;
};
}
namespace std {
template<typename T> struct Y {};
}
}
namespace test1 {
template<typename T> void f1(T) { } // expected-note{{here}}
class X {
template<typename T> friend void f0(T);
template<typename T> friend void f1(T);
};
template<typename T> void f0(T) { }
template<typename T> void f1(T) { } // expected-error{{redefinition}}
}
// PR4768
namespace test2 {
template<typename T> struct X0 {
template<typename U> friend struct X0;
};
template<typename T> struct X0<T*> {
template<typename U> friend struct X0;
};
template<> struct X0<int> {
template<typename U> friend struct X0;
};
template<typename T> struct X1 {
template<typename U> friend void f2(U);
template<typename U> friend void f3(U);
};
template<typename U> void f2(U);
X1<int> x1i;
X0<int*> x0ip;
template<> void f2(int);
// FIXME: Should this declaration of f3 be required for the specialization of
// f3<int> (further below) to work? GCC and EDG don't require it, we do...
template<typename U> void f3(U);
template<> void f3(int);
}
// PR5332
namespace test3 {
template <typename T> class Foo {
template <typename U>
friend class Foo;
};
Foo<int> foo;
template<typename T, T Value> struct X2a;
template<typename T, int Size> struct X2b;
template<typename T>
class X3 {
template<typename U, U Value> friend struct X2a;
// FIXME: the redeclaration note ends up here because redeclaration
// lookup ends up finding the friend target from X3<int>.
template<typename U, T Value> friend struct X2b; // expected-error {{template non-type parameter has a different type 'long' in template redeclaration}} \
// expected-note {{previous non-type template parameter with type 'int' is here}}
};
X3<int> x3i; // okay
X3<long> x3l; // expected-note {{in instantiation}}
}
// PR5716
namespace test4 {
template<typename> struct A {
template<typename T> friend void f(const A<T>&);
};
template<typename T> void f(const A<T>&) {
int a[sizeof(T) ? -1 : -1]; // expected-error {{array with a negative size}}
}
void f() {
f(A<int>()); // expected-note {{in instantiation of function template specialization}}
}
}
namespace test5 {
class outer {
class foo;
template <typename T> friend struct cache;
};
class outer::foo {
template <typename T> friend struct cache;
};
}
// PR6022
namespace PR6022 {
template <class T1, class T2 , class T3 > class A;
namespace inner {
template<class T1, class T2, class T3, class T>
A<T1, T2, T3>& f0(A<T1, T2, T3>&, T);
}
template<class T1, class T2, class T3>
class A {
template<class U1, class U2, class U3, class T>
friend A<U1, U2, U3>& inner::f0(A<U1, U2, U3>&, T);
};
}
namespace FriendTemplateDefinition {
template<unsigned > struct int_c { };
template<typename T>
struct X {
template<unsigned N>
friend void f(X, int_c<N>) {
int value = N;
};
};
void test_X(X<int> x, int_c<5> i5) {
f(x, i5);
}
}
namespace PR7013a {
template<class > struct X0
{
typedef int type;
};
template<typename > struct X1
{
};
template<typename , typename T> struct X2
{
typename T::type e;
};
namespace N
{
template <typename = int, typename = X1<int> > struct X3
{
template <typename T1, typename T2, typename B> friend void op(X2<T1, T2>& , B);
};
template <typename Ch, typename Tr, typename B> void op(X2<Ch, Tr>& , B)
{
X2<int, Tr> s;
}
}
int n()
{
X2<int, X0<int> > ngs;
N::X3<> b;
op(ngs, b);
return 0;
}
}
namespace PR7013b {
template<class > struct X0
{
typedef int type;
};
template<typename > struct X1
{
};
template<typename , typename T> struct X2
{
typename T::type e;
};
namespace N
{
template <typename = X1<int> > struct X3
{
template <typename T1, typename T2, typename B> friend void op(X2<T1, T2>& , B);
};
template <typename Ch, typename Tr, typename B> void op(X2<Ch, Tr>& , B)
{
X2<int, Tr> s;
}
}
int n()
{
X2<int, X0<int> > ngs;
N::X3<> b;
op(ngs, b);
return 0;
}
}
namespace PR8649 {
template<typename T, typename U, unsigned N>
struct X {
template<unsigned M> friend class X<T, U, M>; // expected-error{{partial specialization cannot be declared as a friend}}
};
X<int, float, 7> x;
}
// Don't crash, and error on invalid friend type template.
namespace friend_type_template_no_tag {
template <typename T> struct S {
template <typename U> friend S<U>; // expected-error{{friend type templates must use an elaborated type}}
};
template struct S<int>;
}
namespace PR10660 {
struct A {
template <> friend class B; // expected-error{{extraneous 'template<>' in declaration of class 'B'}}
};
}
namespace rdar11147355 {
template <class T>
struct A {
template <class U> class B;
template <class S> template <class U> friend class A<S>::B; // expected-warning {{dependent nested name specifier 'A<S>::' for friend template declaration is not supported; ignoring this friend declaration}}
private:
int n; // expected-note {{here}}
};
template <class S> template <class U> class A<S>::B {
public:
// FIXME: This should be permitted.
int f(A<S*> a) { return a.n; } // expected-error {{private}}
};
A<double>::B<double> ab;
A<double*> a;
int k = ab.f(a); // expected-note {{instantiation of}}
}
namespace RedeclUnrelated {
struct S {
int packaged_task;
template<typename> class future {
template<typename> friend class packaged_task;
};
future<void> share;
};
}
namespace PR12557 {
template <typename>
struct Foo;
template <typename Foo_>
struct Bar {
typedef Foo_ Foo; // expected-note {{previous}}
template <typename> friend struct Foo; // expected-error {{redefinition of 'Foo' as different kind of symbol}}
};
Bar<int> b;
}
namespace PR12585 {
struct A { };
template<typename> struct B {
template<typename> friend class A::does_not_exist; // \
// expected-error {{friend declaration of 'does_not_exist' does not match any declaration in 'PR12585::A'}}
};
struct C {
template<typename> struct D;
};
template<typename> class E {
int n;
template<typename> friend struct C::D;
};
template<typename T> struct C::D {
int f() {
return E<int>().n;
}
};
int n = C::D<void*>().f();
struct F {
template<int> struct G;
};
template<typename T> struct H {
// FIXME: As with cases above, the note here is on an unhelpful declaration,
// and should point to the declaration of G within F.
template<T> friend struct F::G; // \
// expected-error {{different type 'char' in template redeclaration}} \
// expected-note {{previous}}
};
H<int> h1; // ok
H<char> h2; // expected-note {{instantiation}}
}
// Ensure that we can still instantiate a friend function template
// after the friend declaration is instantiated during the delayed
// parsing of a member function, but before the friend function has
// been parsed.
namespace rdar12350696 {
template <class T> struct A {
void foo() {
A<int> a;
}
template <class U> friend void foo(const A<U> & a) {
int array[sizeof(T) == sizeof(U) ? -1 : 1]; // expected-error {{negative size}}
}
};
void test() {
A<int> b;
foo(b); // expected-note {{in instantiation}}
}
}