llvm-project/clang/test/SemaTemplate/instantiate-self.cpp

90 lines
2.2 KiB
C++

// RUN: %clang_cc1 -std=c++11 -verify %s
// Check that we deal with cases where the instantiation of a class template
// recursively requires the instantiation of the same template.
namespace test1 {
template<typename T> struct A {
struct B { // expected-note {{not complete until the closing '}'}}
B b; // expected-error {{has incomplete type 'test1::A<int>::B'}}
};
B b; // expected-note {{in instantiation of}}
};
A<int> a; // expected-note {{in instantiation of}}
}
namespace test2 {
template<typename T> struct A {
struct B {
struct C {};
char c[1 + C()]; // expected-error {{invalid operands to binary expression}}
friend constexpr int operator+(int, C) { return 4; }
};
B b; // expected-note {{in instantiation of}}
};
A<int> a; // expected-note {{in instantiation of}}
}
namespace test3 {
// PR12317
template<typename T> struct A {
struct B {
enum { Val = 1 };
char c[1 + Val]; // ok
};
B b;
};
A<int> a;
}
namespace test4 {
template<typename T> struct M { typedef int type; };
template<typename T> struct A {
struct B { // expected-note {{not complete until the closing '}'}}
int k[typename A<typename M<T>::type>::B().k[0] + 1]; // expected-error {{incomplete type}}
};
B b; // expected-note {{in instantiation of}}
};
A<int> a; // expected-note {{in instantiation of}}
}
// FIXME: PR12298: Recursive constexpr function template instantiation leads to
// stack overflow.
#if 0
namespace test5 {
template<typename T> struct A {
constexpr T f(T k) { return g(k); }
constexpr T g(T k) {
return k ? f(k-1)+1 : 0;
}
};
// This should be accepted.
constexpr int x = A<int>().f(5);
}
namespace test6 {
template<typename T> constexpr T f(T);
template<typename T> constexpr T g(T t) {
typedef int arr[f(T())];
return t;
}
template<typename T> constexpr T f(T t) {
typedef int arr[g(T())];
return t;
}
// This should be ill-formed.
int n = f(0);
}
namespace test7 {
template<typename T> constexpr T g(T t) {
return t;
}
template<typename T> constexpr T f(T t) {
typedef int arr[g(T())];
return t;
}
// This should be accepted.
int n = f(0);
}
#endif