clang/test/SemaCXX/cxx1z-noexcept-function-type.cpp

   1 // RUN: %clang_cc1 -std=c++14 -verify -fexceptions -fcxx-exceptions %s
   2 // RUN: %clang_cc1 -std=c++17 -verify -fexceptions -fcxx-exceptions %s -Wno-dynamic-exception-spec
   3 // RUN: %clang_cc1 -std=c++14 -verify -fexceptions -fcxx-exceptions -Wno-c++1z-compat-mangling -DNO_COMPAT_MANGLING %s
   4 // RUN: %clang_cc1 -std=c++14 -verify -fexceptions -fcxx-exceptions -Wno-noexcept-type -DNO_COMPAT_MANGLING %s
   5
   6 #if __cplusplus > 201402L
   7
   8 template<typename T> void redecl1() noexcept(noexcept(T())) {} // expected-note {{previous}}
   9 template<typename T> void redecl1() noexcept(noexcept(T())); // ok, same type
  10 template<typename T> void redecl1() noexcept(noexcept(T())) {} // expected-error {{redefinition}}
  11
  12 template<bool A, bool B> void redecl2() noexcept(A); // expected-note {{previous}}
  13 template<bool A, bool B> void redecl2() noexcept(B); // expected-error {{does not match previous}}
  14
  15 // These have the same canonical type, but are still different.
  16 template<typename A, typename B> void redecl3() throw(A); // expected-note {{previous}}
  17 template<typename A, typename B> void redecl3() throw(B); // expected-error {{does not match previous}}
  18
  19 typedef int I;
  20 template<bool B> void redecl4(I) noexcept(B);
  21 template<bool B> void redecl4(I) noexcept(B); // expected-note {{could not match 'void (I) noexcept(false)' (aka 'void (int) noexcept(false)') against 'void (int) noexcept'}}
  22
  23 void (*init_with_exact_type_a)(int) noexcept = redecl4<true>;
  24 void (*init_with_mismatched_type_a)(int) = redecl4<true>;
  25 auto deduce_auto_from_noexcept_function_ptr_a = redecl4<true>;
  26 using DeducedType_a = decltype(deduce_auto_from_noexcept_function_ptr_a);
  27 using DeducedType_a = void (*)(int) noexcept;
  28
  29 void (*init_with_exact_type_b)(int) = redecl4<false>;
  30 void (*init_with_mismatched_type_b)(int) noexcept = redecl4<false>; // expected-error {{does not match required type}}
  31 auto deduce_auto_from_noexcept_function_ptr_b = redecl4<false>;
  32 using DeducedType_b = decltype(deduce_auto_from_noexcept_function_ptr_b);
  33 using DeducedType_b = void (*)(int);
  34
  35 static_assert(noexcept(init_with_exact_type_a(0)));
  36 static_assert(noexcept((+init_with_exact_type_a)(0)));
  37 static_assert(!noexcept(init_with_exact_type_b(0)));
  38 static_assert(!noexcept((+init_with_exact_type_b)(0)));
  39
  40 // Don't look through casts, use the direct type of the expression.
  41 // FIXME: static_cast here would be reasonable, but is not currently permitted.
  42 static_assert(noexcept(static_cast<decltype(init_with_exact_type_a)>(init_with_exact_type_b)(0))); // expected-error {{is not allowed}}
  43 static_assert(noexcept(reinterpret_cast<decltype(init_with_exact_type_a)>(init_with_exact_type_b)(0)));
  44 static_assert(!noexcept(static_cast<decltype(init_with_exact_type_b)>(init_with_exact_type_a)(0)));
  45
  46 template<bool B> auto get_fn() noexcept -> void (*)() noexcept(B) {}
  47 static_assert(noexcept(get_fn<true>()()));
  48 static_assert(!noexcept(get_fn<false>()()));
  49
  50 namespace DependentDefaultCtorExceptionSpec {
  51   template<typename> struct T { static const bool value = true; };
  52
  53   template<class A> struct map {
  54     typedef A a;
  55     map() noexcept(T<a>::value) {}
  56   };
  57
  58   template<class B> struct multimap {
  59     typedef B b;
  60     multimap() noexcept(T<b>::value) {}
  61   };
  62
  63   // Don't crash here.
  64   struct A { multimap<int> Map; } a;
  65
  66   static_assert(noexcept(A()));
  67 }
  68
  69 #endif
  70
  71 namespace CompatWarning {
  72   struct X;
  73
  74   // These cases don't change.
  75   void f0(void p() throw(int));
  76   auto f0() -> void (*)() noexcept(false);
  77
  78   // These cases take an ABI break in C++17 because their parameter / return types change.
  79   void f1(void p() noexcept);
  80   void f2(void (*p)() noexcept(true));
  81   void f3(void (&p)() throw());
  82   void f4(void (X::*p)() throw());
  83   auto f5() -> void (*)() throw();
  84   auto f6() -> void (&)() throw();
  85   auto f7() -> void (X::*)() throw();
  86 #if __cplusplus <= 201402L && !defined(NO_COMPAT_MANGLING)
  87   // expected-warning@-8 {{mangled name of 'f1' will change in C++17 due to non-throwing exception specification in function signature}}
  88   // expected-warning@-8 {{mangled name of 'f2' will change in C++17 due to non-throwing exception specification in function signature}}
  89   // expected-warning@-8 {{mangled name of 'f3' will change in C++17 due to non-throwing exception specification in function signature}}
  90   // expected-warning@-8 {{mangled name of 'f4' will change in C++17 due to non-throwing exception specification in function signature}}
  91   // expected-warning@-8 {{mangled name of 'f5' will change in C++17 due to non-throwing exception specification in function signature}}
  92   // expected-warning@-8 {{mangled name of 'f6' will change in C++17 due to non-throwing exception specification in function signature}}
  93   // expected-warning@-8 {{mangled name of 'f7' will change in C++17 due to non-throwing exception specification in function signature}}
  94 #endif
  95
  96   // An instantiation-dependent exception specification needs to be mangled in
  97   // all language modes, since it participates in SFINAE.
  98   template<typename T> void g(void() throw(T)); // expected-note {{substitution failure}}
  99   template<typename T> void g(...) = delete; // expected-note {{deleted}}
 100   void test_g() { g<void>(nullptr); } // expected-error {{deleted}}
 101
 102   // An instantiation-dependent exception specification needs to be mangled in
 103   // all language modes, since it participates in SFINAE.
 104   template<typename T> void h(void() noexcept(T())); // expected-note {{substitution failure}}
 105   template<typename T> void h(...) = delete; // expected-note {{deleted}}
 106   void test_h() { h<void>(nullptr); } // expected-error {{deleted}}
 107 }
 108
 109 namespace ImplicitExceptionSpec {
 110   struct S {
 111     ~S();
 112     void f(const S &s = S());
 113   };
 114   S::~S() {}
 115 }
 116
 117 namespace Builtins {
 118   // Pick two functions that ought to have the same noexceptness.
 119   extern "C" int strcmp(const char *, const char *);
 120   extern "C" int strncmp(const char *, const char *, decltype(sizeof(0))) noexcept;
 121
 122   // Check we recognized both as builtins.
 123   typedef int arr[strcmp("bar", "foo") + 4 * strncmp("foo", "bar", 4)]; // expected-warning {{variable length array}}
 124   typedef int arr[3];
 125 }
 126
 127 namespace ExplicitInstantiation {
 128   template<typename T> void f() noexcept {}
 129   template<typename T> struct X { void f() noexcept {} };
 130   template void f<int>();
 131   template void X<int>::f();
 132 }
 133
 134 namespace ConversionFunction {
 135   struct A { template<typename T> operator T() noexcept; };
 136   int a = A().operator int();
 137 }
 138
 139 using size_t = decltype(sizeof(0));
 140
 141 namespace OperatorDelete {
 142   struct W {};
 143   struct X {};
 144   struct Y {};
 145   struct Z {};
 146   template<bool N, bool D> struct T {};
 147 }
 148 void *operator new(size_t, OperatorDelete::W) noexcept(false);
 149 void operator delete(void*, OperatorDelete::W) noexcept(false) = delete; // expected-note {{here}}
 150 void *operator new(size_t, OperatorDelete::X) noexcept(false);
 151 void operator delete(void*, OperatorDelete::X) noexcept(true) = delete; // expected-note {{here}}
 152 void *operator new(size_t, OperatorDelete::Y) noexcept(true);
 153 void operator delete(void*, OperatorDelete::Y) noexcept(false) = delete; // expected-note {{here}}
 154 void *operator new(size_t, OperatorDelete::Z) noexcept(true);
 155 void operator delete(void*, OperatorDelete::Z) noexcept(true) = delete; // expected-note {{here}}
 156 template<bool N, bool D> void *operator new(size_t, OperatorDelete::T<N, D>) noexcept(N);
 157 template<bool N, bool D> void operator delete(void*, OperatorDelete::T<N, D>) noexcept(D) = delete; // expected-note 4{{here}}
 158 namespace OperatorDelete {
 159   struct A { A(); };
 160   A *w = new (W{}) A; // expected-error {{deleted function}}
 161   A *x = new (X{}) A; // expected-error {{deleted function}}
 162   A *y = new (Y{}) A; // expected-error {{deleted function}}
 163   A *z = new (Z{}) A; // expected-error {{deleted function}}
 164
 165   A *t00 = new (T<false, false>{}) A; // expected-error {{deleted function}}
 166   A *t01 = new (T<false, true>{}) A; // expected-error {{deleted function}}
 167   A *t10 = new (T<true, false>{}) A; // expected-error {{deleted function}}
 168   A *t11 = new (T<true, true>{}) A; // expected-error {{deleted function}}
 169 }