Fixed some build issues

modules/hal/include/opencv2/hal.hpp

@@ -247,15 +247,7 @@ template<typename T> struct OpAbsDiff
     typedef T type1;
     typedef T type2;
     typedef T rtype;
-    T operator()(T a, T b) const { return (T)std::abs(a - b); }
+    T operator()(T a, T b) const { return a > b ? a - b : b - a; }
-};
-
-template<typename T, typename WT=T> struct OpAbsDiffS
-{
-    typedef T type1;
-    typedef WT type2;
-    typedef T rtype;
-    T operator()(T a, WT b) const { return saturate_cast<T>(std::abs(a - b)); }
 };
 
 template<typename T> struct OpAnd

modules/hal/samples/simple_hal/CMakeLists.txt

@@ -9,4 +9,3 @@ endif()
 add_library(simple_hal simple.cpp)
 set(OPENCV_HAL_DIR "${CMAKE_CURRENT_SOURCE_DIR}/../..")
 target_include_directories(simple_hal PUBLIC ${CMAKE_CURRENT_SOURCE_DIR} ${OPENCV_HAL_DIR}/include)
-

modules/hal/samples/simple_hal/simple.cpp

@@ -31,4 +31,3 @@ int slow_not8u(const uchar* src1, size_t step1, const uchar* src2, size_t step2,
             dst[x] = ~src1[x];
     return cv::hal::Error::Ok;
 }
-