176 lines · cpp
1// RUN: %clang_cc1 -fsyntax-only -verify %s2 3template<typename T> struct A { };4 5// Top-level cv-qualifiers of P's type are ignored for type deduction.6template<typename T> A<T> f0(const T);7 8void test_f0(int i, const int ci) {9 A<int> a0 = f0(i);10 A<int> a1 = f0(ci);11}12 13// If P is a reference type, the type referred to by P is used for type 14// deduction.15template<typename T> A<T> f1(T&);16 17void test_f1(int i, const int ci, volatile int vi) {18 A<int> a0 = f1(i);19 A<const int> a1 = f1(ci);20 A<volatile int> a2 = f1(vi);21}22 23template<typename T, unsigned N> struct B { };24template<typename T, unsigned N> B<T, N> g0(T (&array)[N]);25template<typename T, unsigned N> B<T, N> g0b(const T (&array)[N]);26 27void test_g0() {28 int array0[5];29 B<int, 5> b0 = g0(array0);30 const int array1[] = { 1, 2, 3};31 B<const int, 3> b1 = g0(array1);32 B<int, 3> b2 = g0b(array1);33}34 35template<typename T> B<T, 0> g1(const A<T>&);36 37void test_g1(A<float> af) {38 B<float, 0> b0 = g1(af);39 B<int, 0> b1 = g1(A<int>());40}41 42// - If the original P is a reference type, the deduced A (i.e., the type43// referred to by the reference) can be more cv-qualified than the 44// transformed A.45template<typename T> A<T> f2(const T&);46 47void test_f2(int i, const int ci, volatile int vi) {48 A<int> a0 = f2(i);49 A<int> a1 = f2(ci);50 A<volatile int> a2 = f2(vi);51}52 53// PR591354template <typename T, int N>55void Foo(const T (&a)[N]) {56 T x;57 x = 0;58}59 60const int a[1] = { 0 };61 62void Test() {63 Foo(a);64}65 66// - The transformed A can be another pointer or pointer to member type that 67// can be converted to the deduced A via a qualification conversion (4.4).68template<typename T> A<T> f3(T * * const * const);69 70void test_f3(int ***ip, volatile int ***vip) {71 A<int> a0 = f3(ip);72 A<volatile int> a1 = f3(vip);73}74 75// Also accept conversions for pointer types which require removing76// [[noreturn]].77namespace noreturn_stripping {78 template <class R>79 void f(R (*function)());80 81 void g() __attribute__ ((__noreturn__));82 void h();83 void test() {84 f(g);85 f(h);86 }87}88 89// - If P is a class, and P has the form template-id, then A can be a 90// derived class of the deduced A. Likewise, if P is a pointer to a class91// of the form template-id, A can be a pointer to a derived class pointed 92// to by the deduced A.93template<typename T, int I> struct C { };94 95struct D : public C<int, 1> { };96struct E : public D { };97struct F : A<float> { };98struct G : A<float>, C<int, 1> { };99 100template<typename T, int I>101 C<T, I> *f4a(const C<T, I>&);102template<typename T, int I>103 C<T, I> *f4b(C<T, I>);104template<typename T, int I>105 C<T, I> *f4c(C<T, I>*);106int *f4c(...);107 108void test_f4(D d, E e, F f, G g) {109 C<int, 1> *ci1a = f4a(d);110 C<int, 1> *ci2a = f4a(e);111 C<int, 1> *ci1b = f4b(d);112 C<int, 1> *ci2b = f4b(e);113 C<int, 1> *ci1c = f4c(&d);114 C<int, 1> *ci2c = f4c(&e);115 C<int, 1> *ci3c = f4c(&g);116 int *ip1 = f4c(&f);117}118 119// PR8462120namespace N {121 struct T0;122 struct T1;123 124 template<typename X, typename Y> struct B {};125 126 struct J : B<T0,T0> {};127 struct K : B<T1,T1> {};128 129 struct D : J, K {};130 131 template<typename X, typename Y> void F(B<Y,X>);132 133 void test()134 {135 D d; 136 N::F<T0>(d); // Fails137 N::F<T1>(d); // OK138 }139}140 141namespace PR9233 {142 template<typename T> void f(const T **q); // expected-note{{candidate template ignored: deduced type 'const int **' of 1st parameter does not match adjusted type 'int **' of argument [with T = int]}}143 144 void g(int **p) {145 f(p); // expected-error{{no matching function for call to 'f'}}146 }147 148}149 150namespace PR27155 {151 152struct B {};153 154template<class T, int i> struct D : T {};155template<class T> void Foo(D<T, 1>);156 157int fn() {158 D<D<B, 1>, 0> f;159 Foo(f);160}161 162}163 164namespace PR28195 {165 166template<int N> struct B {};167struct D : B<0>, B<1> {};168 169template<int N> int callee(B<N>); // expected-note{{failed template argument deduction}}170 171int caller() {172 callee(D()); // expected-error{{no matching function}}173}174 175}176