vector deduction guides warning: variable length arrays in C++ are a Clang extension

[AlexeySachkov]

SYCL-CTS/tests/vector_deduction_guides/vec_deduction_guides.cpp

Lines 30 to 36 in 9691bc0

	template <typename T>
	class check_vec_deduction {
	public:
	void operator()(const std::string& type) {
	type_name = type;
	T data[max_size];

If I understand correctly, we need to replace const with constexpr static here:

SYCL-CTS/tests/vector_deduction_guides/vec_deduction_guides.cpp

Lines 66 to 67 in 9691bc0

	private:
	const int max_size = 16;

The fact that class member variable is defined as const doesn't make it into a compile-time-known constant, it only means that it is immutable.

Build log:

[834/1195] Building CXX object tests/vector_deduction_guides/CMakeFiles/test_vector_deduction_guides_objects.dir/vec_deduction_guides.cpp.o
../tests/vector_deduction_guides/vec_deduction_guides.cpp:36:12: warning: variable length arrays in C++ are a Clang extension [-Wvla-cxx-extension]
   36 |     T data[max_size];
      |            ^~~~~~~~
../tests/vector_deduction_guides/../common/../common/type_coverage.h:404:5: note: in instantiation of member function 'vec_deduction_guides::check_vec_deduction<float>::operator()' requested here
  404 |   ((action<types, actionArgsT...>{}(std::forward<argsT>(args)...,
      |     ^
../tests/vector_deduction_guides/vec_deduction_guides.cpp:90:3: note: in instantiation of function template specialization 'for_all_types<vec_deduction_guides::check_vec_deduction, char, signed char, unsigned char, short, unsigned
short, unsigned int, long, unsigned long, long long, unsigned long long, bool, float>' requested here
   90 |   for_all_types<check_vec_deduction>(deduction::vector_types);
      |   ^
../tests/vector_deduction_guides/../common/disabled_for_test_case.h:42:3: note: expanded from macro 'DISABLED_FOR_TEST_CASE'
   42 |   INTERNAL_CTS_DISABLED_FOR_TEST_CASE(__VA_ARGS__)
      |   ^
../tests/vector_deduction_guides/../common/disabled_for_test_case.h:130:40: note: expanded from macro 'INTERNAL_CTS_DISABLED_FOR_TEST_CASE'
  130 |   INTERNAL_CTS_MAYBE_DISABLE_TEST_CASE(INTERNAL_CTS_ENABLED_TEST_CASE, \
      |                                        ^
../tests/vector_deduction_guides/vec_deduction_guides.cpp:36:12: note: implicit use of 'this' pointer is only allowed within the evaluation of a call to a 'constexpr' member function
   36 |     T data[max_size];
      |            ^