test/SemaCXX/MicrosoftCompatibility.cpp

// RUN: %clang_cc1 %s -triple i686-pc-win32 -fsyntax-only -std=c++11 -Wmicrosoft -verify -fms-compatibility -fexceptions -fcxx-exceptions -fms-compatibility-version=19.28
// RUN: %clang_cc1 %s -triple i686-pc-win32 -fsyntax-only -std=c++11 -Wmicrosoft -verify -fms-compatibility -fexceptions -fcxx-exceptions -fms-compatibility-version=19.27
// RUN: %clang_cc1 %s -triple i686-pc-win32 -fsyntax-only -std=c++11 -Wmicrosoft -verify -fms-compatibility -fexceptions -fcxx-exceptions -fms-compatibility-version=19.00
// RUN: %clang_cc1 %s -triple i686-pc-win32 -fsyntax-only -std=c++11 -Wmicrosoft -verify -fms-compatibility -fexceptions -fcxx-exceptions -fms-compatibility-version=18.00
// RUN: %clang_cc1 %s -triple i686-pc-win32 -fsyntax-only -std=c++17 -Wmicrosoft -verify -fms-compatibility -fexceptions -fcxx-exceptions


#if defined(_HAS_CHAR16_T_LANGUAGE_SUPPORT) && _HAS_CHAR16_T_LANGUAGE_SUPPORT
char16_t x;
char32_t y;
#else
typedef unsigned short char16_t;
typedef unsigned int char32_t;
#endif

_Atomic(int) z;
template <typename T>
struct _Atomic {
  _Atomic() {}
  ~_Atomic() {}
};
template <typename T>
struct atomic : _Atomic<T> {
  typedef _Atomic<T> TheBase;
  TheBase field;
};
_Atomic(int) alpha;

typename decltype(3) a; // expected-warning {{expected a qualified name after 'typename'}}

namespace ms_conversion_rules {

void f(float a);
void f(int a);
#if _MSC_VER >= 1928
// expected-note@-3 2 {{candidate function}}
// expected-note@-3 2 {{candidate function}}
#endif

void test()
{
    long a = 0;
    f((long)0);
    f(a);
#if _MSC_VER >= 1928
// expected-error@-3 {{call to 'f' is ambiguous}}
// expected-error@-3 {{call to 'f' is ambiguous}}
#endif
}

}


namespace ms_predefined_types {
  // ::type_info is a built-in forward class declaration.
  void f(const type_info &a);
  void f(size_t);
}


namespace ms_protected_scope {
  struct C { C(); };

  int jump_over_variable_init(bool b) {
    if (b)
      goto foo; // expected-warning {{jump from this goto statement to its label is a Microsoft extension}}
    C c; // expected-note {{jump bypasses variable initialization}}
  foo:
    return 1;
  }

struct Y {
  ~Y();
};

void jump_over_var_with_dtor() {
  goto end; // expected-warning{{jump from this goto statement to its label is a Microsoft extension}}
  Y y; // expected-note {{jump bypasses variable with a non-trivial destructor}}
 end:
    ;
}

  void jump_over_variable_case(int c) {
    switch (c) {
    case 0:
      int x = 56; // expected-note {{jump bypasses variable initialization}}
    case 1:       // expected-error {{cannot jump}}
      x = 10;
    }
  }


void exception_jump() {
  goto l2; // expected-error {{cannot jump}}
  try { // expected-note {{jump bypasses initialization of try block}}
     l2: ;
  } catch(int) {
  }
}

int jump_over_indirect_goto() {
  static void *ps[] = { &&a0 };
  goto *&&a0; // expected-warning {{jump from this goto statement to its label is a Microsoft extension}}
  int a = 3; // expected-note {{jump bypasses variable initialization}}
 a0:
  return 0;
}

}

namespace PR11826 {
  struct pair {
    pair(int v) { }
#if _MSC_VER >= 1900
    void operator=(pair&& rhs) { } // expected-note {{copy constructor is implicitly deleted because 'pair' has a user-declared move assignment operator}}
#else
    void operator=(pair&& rhs) { }
#endif
  };
  void f() {
    pair p0(3);
#if _MSC_VER >= 1900
    pair p = p0; // expected-error {{call to implicitly-deleted copy constructor of 'pair'}}
#else
    pair p = p0;
#endif
  }
}

namespace PR11826_for_symmetry {
  struct pair {
    pair(int v) { }
#if _MSC_VER >= 1900
    pair(pair&& rhs) { } // expected-note {{copy assignment operator is implicitly deleted because 'pair' has a user-declared move constructor}}
#else
    pair(pair&& rhs) { }
#endif
  };
  void f() {
    pair p0(3);
    pair p(4);
#if _MSC_VER >= 1900
    p = p0; // expected-error {{object of type 'pair' cannot be assigned because its copy assignment operator is implicitly deleted}}
#else
    p = p0;
#endif
  }
}

namespace ms_using_declaration_bug {

class A {
public:
  int f();
};

class B : public A {
private:
  using A::f;
  void g() {
    f(); // no diagnostic
  }
};

class C : public B {
private:
  using B::f; // expected-warning {{using declaration referring to inaccessible member 'ms_using_declaration_bug::B::f' (which refers to accessible member 'ms_using_declaration_bug::A::f') is a Microsoft compatibility extension}}
};

}

namespace using_tag_redeclaration
{
  struct S;
  namespace N {
    using ::using_tag_redeclaration::S;
    struct S {}; // expected-note {{previous definition is here}}
  }
  void f() {
    N::S s1;
    S s2;
  }
  void g() {
    struct S; // expected-note {{forward declaration of 'S'}}
    S s3; // expected-error {{variable has incomplete type 'S'}}
  }
  void h() {
    using ::using_tag_redeclaration::S;
    struct S {}; // expected-error {{redefinition of 'S'}}
  }
}


namespace MissingTypename {

template<class T> class A {
public:
	 typedef int TYPE;
};

template<class T> class B {
public:
	 typedef int TYPE;
};


template<class T, class U>
class C : private A<T>, public B<U> {
public:
   typedef A<T> Base1;
   typedef B<U> Base2;
   typedef A<U> Base3;

   A<T>::TYPE a1; // expected-warning {{implicit 'typename' is a C++20 extension}}
   Base1::TYPE a2; // expected-warning {{implicit 'typename' is a C++20 extension}}

   B<U>::TYPE a3; // expected-warning {{implicit 'typename' is a C++20 extension}}
   Base2::TYPE a4; // expected-warning {{implicit 'typename' is a C++20 extension}}

   A<U>::TYPE a5; // expected-warning {{implicit 'typename' is a C++20 extension}}
   Base3::TYPE a6; // expected-warning {{implicit 'typename' is a C++20 extension}}
 };

class D {
public:
    typedef int Type;
};

template <class T>
void function_missing_typename(const T::Type param)// expected-warning {{missing 'typename'}}
{
    const T::Type var = 2; // expected-warning {{missing 'typename'}}
}

template void function_missing_typename<D>(const D::Type param);

}

//MSVC allows forward enum declaration
enum ENUM; // expected-warning {{forward references to 'enum' types are a Microsoft extension}}
ENUM *var = 0;
ENUM var2 = (ENUM)0;
enum ENUM1* var3 = 0;// expected-warning {{forward references to 'enum' types are a Microsoft extension}}

enum ENUM1 { kA };
enum ENUM1;  // This way round is fine.

enum ENUM2 {
	ENUM2_a = (enum ENUM2) 0,
	ENUM2_b = 0x9FFFFFFF, // expected-warning {{enumerator value is not representable in the underlying type 'int'}}
	ENUM2_c = 0x100000000 // expected-warning {{enumerator value is not representable in the underlying type 'int'}}
};

namespace NsEnumForwardDecl {
  enum E *p; // expected-warning {{forward references to 'enum' types are a Microsoft extension}}
  extern E e;
}
// Clang used to complain that NsEnumForwardDecl::E was undeclared below.
NsEnumForwardDecl::E NsEnumForwardDecl_e;
namespace NsEnumForwardDecl {
  extern E e;
}

namespace PR11791 {
  template<class _Ty>
  void del(_Ty *_Ptr) {
    _Ptr->~_Ty();  // expected-warning {{pseudo-destructors on type void are a Microsoft extension}}
  }

  void f() {
    int* a = 0;
    del((void*)a);  // expected-note {{in instantiation of function template specialization}}
  }
}

namespace IntToNullPtrConv {
  struct Foo {
    static const int ZERO = 0;
    typedef void (Foo::*MemberFcnPtr)();
  };

  struct Bar {
    const Foo::MemberFcnPtr pB;
  };

  Bar g_bar = { (Foo::MemberFcnPtr)Foo::ZERO };

  template<int N> int *get_n() { return N; }   // expected-warning {{expression which evaluates to zero treated as a null pointer constant}}
  int *g_nullptr = get_n<0>();  // expected-note {{in instantiation of function template specialization}}

  // FIXME: MSVC accepts this.
  constexpr float k = 0;
  int *p1 = (int)k; // expected-error {{cannot initialize}}

  constexpr int n = 0;
  const int &r = n;
  int *p2 = (int)r; // expected-error {{cannot initialize}}

  constexpr int f() { return 0; }
  int *p = f(); // expected-error {{cannot initialize}}
}

namespace signed_hex_i64 {
void f(long long);
void f(int);
void g() {
  // This is an ambiguous call in standard C++.
  // This calls f(long long) in Microsoft mode because LL is always signed.
  f(0xffffffffffffffffLL);
  f(0xffffffffffffffffi64);
}
}

typedef void (*FnPtrTy)();
void (*PR23733_1)() = static_cast<FnPtrTy>((void *)0); // expected-warning {{static_cast between pointer-to-function and pointer-to-object is a Microsoft extension}}
void (*PR23733_2)() = FnPtrTy((void *)0);
void (*PR23733_3)() = (FnPtrTy)((void *)0);
void (*PR23733_4)() = reinterpret_cast<FnPtrTy>((void *)0);

long function_prototype(int a);
long (*function_ptr)(int a);

void function_to_voidptr_conv() {
  void *a1 = function_prototype;  // expected-warning {{implicit conversion between pointer-to-function and pointer-to-object is a Microsoft extension}}
  void *a2 = &function_prototype; // expected-warning {{implicit conversion between pointer-to-function and pointer-to-object is a Microsoft extension}}
  void *a3 = function_ptr;        // expected-warning {{implicit conversion between pointer-to-function and pointer-to-object is a Microsoft extension}}
}

namespace member_lookup {

template<typename T>
struct ConfuseLookup {
  T* m_val;
  struct m_val {
    static size_t ms_test;
  };
};

// Microsoft mode allows explicit constructor calls
// This could confuse name lookup in cases such as this
template<typename T>
size_t ConfuseLookup<T>::m_val::ms_test
  = size_t(&(char&)(reinterpret_cast<ConfuseLookup<T>*>(0)->m_val));

void instantiate() { ConfuseLookup<int>::m_val::ms_test = 1; }
}


// Microsoft doesn't validate exception specification.
namespace microsoft_exception_spec {

void foo(); // expected-note {{previous declaration}}
void foo() throw(); // expected-warning {{exception specification in declaration does not match previous declaration}}

#if __cplusplus < 201703L
void r6() throw(...); // expected-note {{previous declaration}}
void r6() throw(int); // expected-warning {{exception specification in declaration does not match previous declaration}}

struct Base {
  virtual void f2();
  virtual void f3() throw(...);
};

struct Derived : Base {
  virtual void f2() throw(...);
  virtual void f3();
};
#endif

class A {
  virtual ~A() throw();
#if __cplusplus <= 199711L
  // expected-note@-2 {{overridden virtual function is here}}
#endif
};

class B : public A {
  virtual ~B();
#if __cplusplus <= 199711L
  // expected-warning@-2 {{exception specification of overriding function is more lax than base version}}
#endif
};

void f4() throw(); // expected-note {{previous declaration is here}}
void f4() {}       // expected-warning {{'f4' is missing exception specification 'throw()'}}

__declspec(nothrow) void f5();
void f5() {}

void f6() noexcept; // expected-note {{previous declaration is here}}
void f6() {}        // expected-error {{'f6' is missing exception specification 'noexcept'}}
}

namespace PR43265 {
template <int N> // expected-note {{template parameter is declared here}}
struct Foo {
  static const int N = 42; // expected-warning {{declaration of 'N' shadows template parameter}}
};
}

namespace Inner_Outer_same_template_param_name {
template <typename T> // expected-note {{template parameter is declared here}}
struct Outmost {
  template <typename T> // expected-warning {{declaration of 'T' shadows template parameter}}
  struct Inner {
    void f() {
      T *var;
    }
  };
};
}