MAINT: Remove warning when checking AVX512f on MSVC

[mattip]

This appears in the checks for AVX512f features. @seiko2plus will the failure to build disable the optimization?

[seiko2plus]

will the failure to build disable the optimization?

No, test files with the prefix extra_ testing certain intrinsics that not necessarily to be supported by the compiler, usually functions or intrinsics that have no native support by the hardware.

checks/extra_avx512f_reduce.c enables the definition NPY_HAVE_AVX512F_REDUCE, see the following branch for more clarification:

numpy/numpy/core/src/common/simd/avx512/arithmetic.h

Lines 368 to 380 in 6f5ad73

	#ifdef NPY_HAVE_AVX512F_REDUCE
	#define npyv_sum_u32 _mm512_reduce_add_epi32
	#define npyv_sum_u64 _mm512_reduce_add_epi64
	#define npyv_sum_f32 _mm512_reduce_add_ps
	#define npyv_sum_f64 _mm512_reduce_add_pd
	#else
	NPY_FINLINE npy_uint32 npyv_sum_u32(npyv_u32 a)
	{
	__m256i half = _mm256_add_epi32(npyv512_lower_si256(a), npyv512_higher_si256(a));
	__m128i quarter = _mm_add_epi32(_mm256_castsi256_si128(half), _mm256_extracti128_si256(half, 1));
	quarter = _mm_hadd_epi32(quarter, quarter);
	return _mm_cvtsi128_si32(_mm_hadd_epi32(quarter, quarter));
	}

[seiko2plus]

Thank you Matti