clang/test/SemaCXX/recovery-expr-type.cpp

   1 // RUN: %clang_cc1 -triple=x86_64-unknown-unknown -o - %s -std=gnu++17 -fsyntax-only -verify
   2 // RUN: %clang_cc1 -triple=x86_64-unknown-unknown -o - %s -std=gnu++20 -fsyntax-only -verify
   3
   4
   5 namespace test0 {
   6 struct Indestructible {
   7   // Indestructible();
   8   ~Indestructible() = delete; // expected-note 2{{deleted}}
   9 };
  10 Indestructible make_indestructible();
  11
  12 void test() {
  13   // no crash.
  14   int s = sizeof(make_indestructible()); // expected-error {{deleted}}
  15   constexpr int ss = sizeof(make_indestructible()); // expected-error {{deleted}}
  16   static_assert(ss, "");
  17   int array[ss];
  18 }
  19 }
  20
  21 namespace test1 {
  22 constexpr int foo() { return 1; } // expected-note {{candidate function not viable}}
  23 // verify the "not an integral constant expression" diagnostic is suppressed.
  24 static_assert(1 == foo(1), ""); // expected-error {{no matching function}}
  25 }
  26
  27 namespace test2 {
  28 void foo(); // expected-note 3{{requires 0 arguments}}
  29 void func() {
  30   // verify that "field has incomplete type" diagnostic is suppressed.
  31   typeof(foo(42)) var; // expected-error {{no matching function}} \
  32
  33   // FIXME: suppress the "cannot initialize a variable" diagnostic.
  34   int a = foo(1); // expected-error {{no matching function}} \
  35                   // expected-error {{cannot initialize a variable of type}}
  36
  37   // FIXME: suppress the "invalid application" diagnostic.
  38   int s = sizeof(foo(42)); // expected-error {{no matching function}} \
  39                            // expected-error {{invalid application of 'sizeof'}}
  40 };
  41 }
  42
  43 namespace test3 {
  44 template <int N>
  45 constexpr int templated() __attribute__((enable_if(N, ""))) { // expected-note {{candidate disabled}}
  46   return 1;
  47 }
  48 // verify that "constexpr variable must be initialized" diagnostic is suppressed.
  49 constexpr int A = templated<0>(); // expected-error{{no matching function}}
  50
  51 template <typename T>
  52 struct AA {
  53   template <typename U>
  54   static constexpr int getB() { // expected-note{{candidate template ignored}}
  55     return 2;
  56   }
  57   static constexpr int foo2() {
  58     return AA<T>::getB(); // expected-error{{no matching function for call to 'getB'}}
  59   }
  60 };
  61 // FIXME: should we suppress the "be initialized by a constant expression" diagnostic?
  62 constexpr auto x2 = AA<int>::foo2(); // expected-error {{be initialized by a constant expression}} \
  63                                      // expected-note {{in instantiation of member function}}
  64 }
  65
  66 // verify no assertion failure on violating value category.
  67 namespace test4 {
  68 int &&f(int);  // expected-note {{candidate function not viable}}
  69 int &&k = f(); // expected-error {{no matching function for call}}
  70 }
  71
  72 // verify that "type 'double' cannot bind to a value of unrelated type 'int'" diagnostic is suppressed.
  73 namespace test5 {
  74   template<typename T> using U = T; // expected-note {{template parameter is declared here}}
  75   template<typename...Ts> U<Ts...>& f(); // expected-error {{pack expansion used as argument for non-pack parameter of alias template}}
  76   double &s1 = f(); // expected-error {{no matching function}}
  77 }
  78
  79 namespace test6 {
  80 struct T {
  81   T() = delete; // expected-note {{has been explicitly marked deleted here}}
  82 };
  83
  84 void func() {
  85   // verify that no -Wunused-value diagnostic.
  86   (T(T())); // expected-error {{call to deleted constructor}}
  87 }
  88 }
  89
  90 // verify the secondary diagnostic "no matching function" is emitted.
  91 namespace test7 {
  92 struct C {
  93   C() = delete; // expected-note {{has been explicitly marked deleted}}
  94 };
  95 void f(C &); // expected-note {{candidate function not viable: expects an lvalue for 1st argument}}
  96 void test() {
  97   f(C()); // expected-error {{call to deleted constructor}} \
  98              expected-error {{no matching function for call}}
  99 }
 100 }
 101
 102 // verify the secondary diagnostic "cannot initialize" is emitted.
 103 namespace test8 {
 104 typedef int arr[];
 105 int v = arr(); // expected-error {{array types cannot be value-initialized}} \
 106                   expected-error {{cannot initialize a variable of type 'int' with an rvalue of type 'arr'}}
 107 }
 108
 109 namespace test9 {
 110 auto f(); // expected-note {{candidate function not viable}}
 111 // verify no crash on evaluating the size of undeduced auto type.
 112 static_assert(sizeof(f(1)), ""); // expected-error {{no matching function for call to 'f'}}
 113 }
 114
 115 namespace test10 {
 116 // Ensure we don't assert here.
 117 int f(); // expected-note {{candidate}}
 118 template<typename T> const int k = f(T()); // expected-error {{no matching function}}
 119 static_assert(k<int> == 1, ""); // expected-note {{instantiation of}}
 120 }
 121
 122 namespace test11 {
 123 // Verify we do not assert()-fail here.
 124 template <class T> void foo(T &t);
 125 template <typename T>
 126 void bar(T t) {
 127   foo(t);
 128 }
 129
 130 template <typename T = void *>
 131 struct S { // expected-note {{candidate}}
 132   S(T t);  // expected-note {{candidate}}
 133   ~S();
 134 };
 135 template <typename T> S(T t) -> S<void *>;
 136
 137 void baz() {
 138   bar(S(123)); // expected-error {{no matching conversion for functional-style cast from 'int' to 'S<void *>'}}
 139 }
 140 } // namespace test11
 141
 142 namespace test12 {
 143 // Verify we do not crash.
 144 int fun(int *foo = no_such_function()); // expected-error {{undeclared identifier}}
 145 void crash1() { fun(); }
 146 void crash2() { constexpr int s = fun(); }
 147 } // namespace test12
 148
 149 namespace test13 {
 150 enum Circular {             // expected-note {{not complete until the closing '}'}}
 151   Circular_A = Circular(1), // expected-error {{'Circular' is an incomplete type}}
 152 };
 153 // Enumerators can be evaluated (they evaluate as zero, but we don't care).
 154 static_assert(Circular_A == 0 && Circular_A != 0, ""); // expected-error {{static assertion failed}} \
 155                                                        // expected-note {{evaluates to '0 != 0'}}
 156 }
 157
 158 namespace test14 {
 159 extern "C" void *memset(void *, int b, unsigned long) {
 160   int * const c(undef()); // expected-error {{undeclared identifier}}
 161   // Verify we do not crash on evaluating *c whose initializer is a NULL-type ParenListExpr!
 162   memset(c, 0, *c); // crash1
 163
 164   b = __builtin_object_size(c, 0); // crash2
 165 }
 166 }
 167
 168 namespace test15 {
 169 void f() {
 170   struct {
 171     void m(int (&)[undefined()]) {} // expected-error {{undeclared identifier}}
 172   } S;
 173   S.m(1); // no crash
 174 }
 175 }
 176
 177 namespace test16 {
 178 // verify we do not crash on incomplete class type.
 179 template<typename T, typename U> struct A; // expected-note 5{{template is declared here}}
 180 A<int, int> foo() { // expected-error {{implicit instantiation of undefined template}}
 181   if (1 == 1)
 182     return A<int, int>{1}; // expected-error 2{{implicit instantiation of undefined template}}
 183   return A<int, int>(1); // expected-error 2{{implicit instantiation of undefined template}}
 184 }
 185 }