xref: /aosp_15_r20/external/clang/test/CXX/temp/temp.param/p9-0x.cpp (revision 67e74705e28f6214e480b399dd47ea732279e315)
1*67e74705SXin Li // RUN: %clang_cc1 -std=c++11 -fsyntax-only -verify %s
2*67e74705SXin Li 
3*67e74705SXin Li // A default template-argument may be specified for any kind of
4*67e74705SXin Li // template-parameter that is not a template parameter pack.
5*67e74705SXin Li template<typename ...Types = int> // expected-error{{template parameter pack cannot have a default argument}}
6*67e74705SXin Li struct X0;
7*67e74705SXin Li 
8*67e74705SXin Li template<int ...Values = 0> // expected-error{{template parameter pack cannot have a default argument}}
9*67e74705SXin Li struct X1;
10*67e74705SXin Li 
11*67e74705SXin Li template<typename T> struct vector;
12*67e74705SXin Li 
13*67e74705SXin Li template<template<class> class ...Templates = vector> // expected-error{{template parameter pack cannot have a default argument}}
14*67e74705SXin Li struct X2;
15*67e74705SXin Li 
16*67e74705SXin Li struct X3 {
17*67e74705SXin Li   template<typename T = int> // expected-error{{default template argument not permitted on a friend template}}
18*67e74705SXin Li   friend void f0(X3);
19*67e74705SXin Li 
20*67e74705SXin Li   template<typename T = int>
f1(X3)21*67e74705SXin Li   friend void f1(X3) {
22*67e74705SXin Li   }
23*67e74705SXin Li };
24*67e74705SXin Li 
25*67e74705SXin Li namespace PR8748 {
26*67e74705SXin Li   // Testcase 1
27*67e74705SXin Li   struct A0 { template<typename U> struct B; };
28*67e74705SXin Li   template<typename U = int> struct A0::B { };
29*67e74705SXin Li 
30*67e74705SXin Li   // Testcase 2
31*67e74705SXin Li   template<typename T> struct A1 { template<typename U> struct B; };
32*67e74705SXin Li   template<typename T> template<typename U = int> struct A1<T>::B { }; // expected-error{{cannot add a default template argument to the definition of a member of a class template}}
33*67e74705SXin Li 
34*67e74705SXin Li   // Testcase 3
35*67e74705SXin Li   template<typename T>
36*67e74705SXin Li   struct X2 {
37*67e74705SXin Li     void f0();
38*67e74705SXin Li     template<typename U> void f1();
39*67e74705SXin Li   };
40*67e74705SXin Li 
f0()41*67e74705SXin Li   template<typename T = int> void X2<T>::f0() { } // expected-error{{cannot add a default template argument to the definition of a member of a class template}}
f1()42*67e74705SXin Li   template<typename T> template<typename U = int> void X2<T>::f1() { } // expected-error{{cannot add a default template argument to the definition of a member of a class template}}
43*67e74705SXin Li 
44*67e74705SXin Li   namespace Inner {
45*67e74705SXin Li     template<typename T> struct X3;
46*67e74705SXin Li     template<typename T> void f2();
47*67e74705SXin Li   }
48*67e74705SXin Li 
49*67e74705SXin Li   // Okay; not class members.
50*67e74705SXin Li   template<typename T = int> struct Inner::X3 { };
f2()51*67e74705SXin Li   template<typename T = int> void Inner::f2() {}
52*67e74705SXin Li }
53*67e74705SXin Li 
54*67e74705SXin Li namespace PR10069 {
55*67e74705SXin Li   template<typename T, T a, T b=0, T c=1>
56*67e74705SXin Li   T f(T x);
57*67e74705SXin Li 
g()58*67e74705SXin Li   void g() {
59*67e74705SXin Li     f<unsigned int, 0>(0);
60*67e74705SXin Li   }
61*67e74705SXin Li }
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