llvm-project/clang/test/SemaCXX/decl-microsoft-call-conv.cpp

// RUN: %clang_cc1 -std=c++14 -triple i686-pc-win32 -fms-extensions -DMSABI -verify %s
// RUN: %clang_cc1 -std=c++14 -triple i686-pc-mingw32 -verify %s
// RUN: %clang_cc1 -std=c++14 -triple i686-pc-mingw32 -fms-extensions -verify %s

typedef void void_fun_t();
typedef void __cdecl cdecl_fun_t();

// Pointers to free functions
void            free_func_default(); // expected-note 2 {{previous declaration is here}}
void __cdecl    free_func_cdecl(); // expected-note 2 {{previous declaration is here}}
void __stdcall  free_func_stdcall(); // expected-note 2 {{previous declaration is here}}
void __fastcall free_func_fastcall(); // expected-note 2 {{previous declaration is here}}
void __vectorcall free_func_vectorcall(); // expected-note 2 {{previous declaration is here}}

void __cdecl    free_func_default();
void __stdcall  free_func_default(); // expected-error {{function declared 'stdcall' here was previously declared without calling convention}}
void __fastcall free_func_default(); // expected-error {{function declared 'fastcall' here was previously declared without calling convention}}

void            free_func_cdecl();
void __stdcall  free_func_cdecl(); // expected-error {{function declared 'stdcall' here was previously declared 'cdecl'}}
void __fastcall free_func_cdecl(); // expected-error {{function declared 'fastcall' here was previously declared 'cdecl'}}

void            free_func_stdcall();
void __cdecl    free_func_stdcall(); // expected-error {{function declared 'cdecl' here was previously declared 'stdcall'}}
void __fastcall free_func_stdcall(); // expected-error {{function declared 'fastcall' here was previously declared 'stdcall'}}

void __cdecl    free_func_fastcall(); // expected-error {{function declared 'cdecl' here was previously declared 'fastcall'}}
void __stdcall  free_func_fastcall(); // expected-error {{function declared 'stdcall' here was previously declared 'fastcall'}}
void            free_func_fastcall();

void __cdecl    free_func_vectorcall(); // expected-error {{function declared 'cdecl' here was previously declared 'vectorcall'}}
void __stdcall  free_func_vectorcall(); // expected-error {{function declared 'stdcall' here was previously declared 'vectorcall'}}
void            free_func_vectorcall();

// Overloaded functions may have different calling conventions
void __fastcall free_func_default(int);
void __cdecl    free_func_default(int *);

void __thiscall free_func_cdecl(char *);
void __cdecl    free_func_cdecl(double);

typedef void void_fun_t();
typedef void __cdecl cdecl_fun_t();

// Pointers to member functions
struct S {
  void            member_default1(); // expected-note {{previous declaration is here}}
  void            member_default2();
  void __cdecl    member_cdecl1();
  void __cdecl    member_cdecl2(); // expected-note {{previous declaration is here}}
  void __thiscall member_thiscall1();
  void __thiscall member_thiscall2(); // expected-note {{previous declaration is here}}
  void __vectorcall member_vectorcall1();
  void __vectorcall member_vectorcall2(); // expected-note {{previous declaration is here}}

  // Typedefs carrying the __cdecl convention are adjusted to __thiscall.
  void_fun_t           member_typedef_default; // expected-note {{previous declaration is here}}
  cdecl_fun_t          member_typedef_cdecl1;  // expected-note {{previous declaration is here}}
  cdecl_fun_t __cdecl  member_typedef_cdecl2;
  void_fun_t __stdcall member_typedef_stdcall;

  // Static member functions can't be __thiscall
  static void            static_member_default1();
  static void            static_member_default2();
  static void            static_member_default3(); // expected-note {{previous declaration is here}}
  static void __cdecl    static_member_cdecl1();
  static void __cdecl    static_member_cdecl2(); // expected-note {{previous declaration is here}}
  static void __stdcall  static_member_stdcall1();
  static void __stdcall  static_member_stdcall2();

  // Variadic functions can't be other than default or __cdecl
  void            member_variadic_default(int x, ...);
  void __cdecl    member_variadic_cdecl(int x, ...);

  static void            static_member_variadic_default(int x, ...);
  static void __cdecl    static_member_variadic_cdecl(int x, ...);

  // Structors can't be other than default in MS ABI environment
#ifdef MSABI
  __vectorcall S(); // expected-warning {{vectorcall calling convention ignored on constructor/destructor}}
#endif
};

void __cdecl    S::member_default1() {} // expected-error {{function declared 'cdecl' here was previously declared without calling convention}}
void __thiscall S::member_default2() {}

void __cdecl   S::member_typedef_default() {} // expected-error {{function declared 'cdecl' here was previously declared without calling convention}}
void __cdecl   S::member_typedef_cdecl1() {} // expected-error {{function declared 'cdecl' here was previously declared without calling convention}}
void __cdecl   S::member_typedef_cdecl2() {}
void __stdcall S::member_typedef_stdcall() {}

void            S::member_cdecl1() {}
void __thiscall S::member_cdecl2() {} // expected-error {{function declared 'thiscall' here was previously declared 'cdecl'}}

void            S::member_thiscall1() {}
void __cdecl    S::member_thiscall2() {} // expected-error {{function declared 'cdecl' here was previously declared 'thiscall'}}

void            S::member_vectorcall1() {}
void __cdecl    S::member_vectorcall2() {} // expected-error {{function declared 'cdecl' here was previously declared 'vectorcall'}}

void            S::static_member_default1() {}
void __cdecl    S::static_member_default2() {}
void __stdcall  S::static_member_default3() {} // expected-error {{function declared 'stdcall' here was previously declared without calling convention}}

void            S::static_member_cdecl1() {}
void __stdcall  S::static_member_cdecl2() {} // expected-error {{function declared 'stdcall' here was previously declared 'cdecl'}}

void __cdecl    S::member_variadic_default(int x, ...) { (void)x; }
void            S::member_variadic_cdecl(int x, ...) { (void)x; }

void __cdecl    S::static_member_variadic_default(int x, ...) { (void)x; }
void            S::static_member_variadic_cdecl(int x, ...) { (void)x; }

// Declare a template using a calling convention.
template <class CharT> inline int __cdecl mystrlen(const CharT *str) {
  int i;
  for (i = 0; str[i]; i++) { }
  return i;
}
extern int sse_strlen(const char *str);
template <> inline int __cdecl mystrlen(const char *str) {
  return sse_strlen(str);
}
void use_tmpl(const char *str, const int *ints) {
  mystrlen(str);
  mystrlen(ints);
}

struct MixedCCStaticOverload {
  static void overloaded(int a);
  static void __stdcall overloaded(short a);
};

void MixedCCStaticOverload::overloaded(int a) {}
void MixedCCStaticOverload::overloaded(short a) {}

// Friend function decls are cdecl by default, not thiscall.  Friend method
// decls should always be redeclarations, because the class cannot be
// incomplete.
struct FriendClass {
  void friend_method() {}
};
void __stdcall friend_stdcall1() {}
class MakeFriendDecls {
  int x;
  friend void FriendClass::friend_method();
  friend void              friend_default();
  friend void              friend_stdcall1();
  friend void __stdcall    friend_stdcall2();
  friend void              friend_stdcall3(); // expected-note {{previous declaration is here}}
};
void           friend_default() {}
void __stdcall friend_stdcall3() {} // expected-error {{function declared 'stdcall' here was previously declared without calling convention}}
void __stdcall friend_stdcall2() {}

// Test functions with multiple attributes.
void __attribute__((noreturn)) __stdcall __attribute__((regparm(1))) multi_attribute(int x);
void multi_attribute(int x) { __builtin_unreachable(); }


// expected-error@+3 {{vectorcall and cdecl attributes are not compatible}}
// expected-error@+2 {{stdcall and cdecl attributes are not compatible}}
// expected-error@+1 {{fastcall and cdecl attributes are not compatible}}
void __cdecl __cdecl __stdcall __cdecl __fastcall __vectorcall multi_cc(int x);

template <typename T> void __stdcall StdcallTemplate(T) {}
template <> void StdcallTemplate<int>(int) {}
template <> void __stdcall StdcallTemplate<short>(short) {}

// FIXME: Note the template, not the implicit instantiation.
// expected-error@+2 {{function declared 'cdecl' here was previously declared 'stdcall}}
// expected-note@+1 {{previous declaration is here}}
template <> void __cdecl StdcallTemplate<long>(long) {}

struct ExactlyInt {
  template <typename T> static int cast_to_int(T) {
    return T::this_is_not_an_int();
  }
};
template <> inline int ExactlyInt::cast_to_int<int>(int x) { return x; }

namespace test2 {
  class foo {
    template <typename T> void bar(T v);
  };
  extern template void foo::bar(const void *);
}

namespace test3 {
  struct foo {
    typedef void bar();
  };
  bool zed(foo::bar *);
  void bah() {}
  void baz() { zed(bah); }
}

namespace test4 {
  class foo {
    template <typename T> static void bar(T v);
  };
  extern template void foo::bar(const void *);
}

namespace test5 {
  template <class T>
  class valarray {
    void bar();
  };
  extern template void valarray<int>::bar();
}

namespace test6 {
  struct foo {
    int bar();
  };
  typedef int bar_t();
  void zed(bar_t foo::*) {
  }
  void baz() {
    zed(&foo::bar);
  }
}

namespace test7 {
  template <typename T>
  struct S {
    void f(T t) {
      t = 42;
    }
  };
  template<> void S<void*>::f(void*);
  void g(S<void*> s, void* p) {
    s.f(p);
  }
}

namespace test8 {
  template <typename T>
  struct S {
    void f(T t) { // expected-note {{previous declaration is here}}
      t = 42; // expected-error {{assigning to 'void *' from incompatible type 'int'}}
    }
  };
  template<> void __cdecl S<void*>::f(void*); // expected-error {{function declared 'cdecl' here was previously declared without calling convention}}
  void g(S<void*> s, void* p) {
    s.f(p); // expected-note {{in instantiation of member function 'test8::S<void *>::f' requested here}}
  }
}

namespace test9 {
  // Used to fail when we forgot to make lambda call operators use __thiscall.
  template <typename F>
  decltype(auto) deduce(F f) {
    return &decltype(f)::operator();
  }
  template <typename C, typename R, typename A>
  decltype(auto) signaturehelper(R (C::*f)(A) const) {
    return R();
  }
  void f() {
    auto l = [](int x) { return x * 2; };
    decltype(signaturehelper(deduce(l))) p;
  }
}