Deprecated implicit copy ctors/assigns in `libcxx/test`

[StephanTLavavej]

MSVC is implementing a new warning (off-by-default) to detect the following deprecated cases (I've heard that Clang and GCC -Wdeprecated can also detect this) in N4928 [class.copy.ctor]/6 (emphasis mine):

If the class definition does not explicitly declare a copy constructor, a non-explicit one is declared implicitly. If the class definition declares a move constructor or move assignment operator, the implicitly declared copy constructor is defined as deleted; otherwise, it is defaulted (9.5). The latter case is deprecated if the class has a user-declared copy assignment operator or a user-declared destructor (D.8).

and [class.copy.assign]/2 (emphasis mine):

If the class definition does not explicitly declare a copy assignment operator, one is declared implicitly. If the class definition declares a move constructor or move assignment operator, the implicitly declared copy assignment operator is defined as deleted; otherwise, it is defaulted (9.5). The latter case is deprecated if the class has a user-declared copy constructor or a user-declared destructor (D.8).

While cleaning up MSVC's STL (see microsoft/STL#3497), I found the following deprecated implicit copy ctors/assigns in libcxx's test suite:

• llvm-project/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.star/op_star.pass.cpp(29):
  • warning C5267: definition of implicit copy constructor for 'A' is deprecated because it has a user-provided destructor

  • llvm-project/libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.star/op_star.pass.cpp

    Lines 24 to 33 in 53689fd

    	class A
    	{
    	int data_;
    	public:
    	A() : data_(1) {}
    	~A() {data_ = -1;}
    	friend bool operator==(const A& x, const A& y)
    	{return x.data_ == y.data_;}
    	};

• llvm-project/libcxx/test/support/deleter_types.h(191):
  • warning C5267: definition of implicit copy constructor for 'CDeleter<A []>' is deprecated because it has a user-provided destructor

  • llvm-project/libcxx/test/support/deleter_types.h

    Lines 181 to 200 in 53689fd

    	template <class T>
    	class CDeleter<T[]> {
    	int state_;
    	public:
    	TEST_CONSTEXPR_CXX23 CDeleter() : state_(0) {}
    	TEST_CONSTEXPR_CXX23 explicit CDeleter(int s) : state_(s) {}
    	template <class U>
    	TEST_CONSTEXPR_CXX23 CDeleter(const CDeleter<U>& d) : state_(d.state()) {}
    	TEST_CONSTEXPR_CXX23 ~CDeleter() {
    	assert(state_ >= 0);
    	state_ = -1;
    	}
    	TEST_CONSTEXPR_CXX23 int state() const { return state_; }
    	TEST_CONSTEXPR_CXX23 void set_state(int i) { state_ = i; }
    	TEST_CONSTEXPR_CXX23 void operator()(T* p) { delete[] p; }
    	};

• llvm-project/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/convert_move.pass.cpp(29):
  • warning C5267: definition of implicit assignment operator for 'B' is deprecated because it has a user-provided destructor
  • warning C5267: definition of implicit copy constructor for 'B' is deprecated because it has a user-provided destructor

  • llvm-project/libcxx/test/std/utilities/tuple/tuple.tuple/tuple.assign/convert_move.pass.cpp

    Lines 26 to 30 in 53689fd

    	struct B {
    	int id_;
    	explicit B(int i = 0) : id_(i) {}
    	virtual ~B() {}
    	};

@CaseyCarter's https://reviews.llvm.org/D144694 fixes other occurrences in any and optional's tests.

[fsb4000]

I've created https://reviews.llvm.org/D144775