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 * test build on VS2012

modules/core/test/test_arithm.cpp

 #include "test_precomp.hpp"
+#include <cmath>
 
 using namespace cv;
 using namespace std;
@@ -1902,11 +1903,6 @@ TEST(Normalize, regression_5876_inplace_change_type)
     EXPECT_EQ(0, cvtest::norm(m, result, NORM_INF));
 }
 
-#ifndef NAN
-#include <limits> // numeric_limits<T>::quiet_NaN()
-#define NAN std::numeric_limits<float>::quiet_NaN()
-#endif
-
 TEST(MinMaxLoc, regression_4955_nans)
 {
     cv::Mat one_mat(2, 2, CV_32F, cv::Scalar(1));