Added more strict checks for empty inputs to compare, meanStdDev and RNG::fill

modules/core/src/arithm.cpp

@@ -1233,7 +1233,8 @@ void cv::compare(InputArray _src1, InputArray _src2, OutputArray _dst, int op)
     CV_Assert( op == CMP_LT || op == CMP_LE || op == CMP_EQ ||
                op == CMP_NE || op == CMP_GE || op == CMP_GT );
 
-    if(_src1.empty() || _src2.empty())
+    CV_Assert(_src1.empty() == _src2.empty());
+    if (_src1.empty() && _src2.empty())
     {
         _dst.release();
         return;

modules/core/src/copy.cpp

@@ -411,7 +411,8 @@ Mat& Mat::operator = (const Scalar& s)
 {
     CV_INSTRUMENT_REGION()
 
-    if (empty()) return *this;
+    if (this->empty())
+        return *this;
 
     const Mat* arrays[] = { this };
     uchar* dptr;

modules/core/src/mean.cpp

@@ -766,11 +766,13 @@ void cv::meanStdDev( InputArray _src, OutputArray _mean, OutputArray _sdv, Input
 {
     CV_INSTRUMENT_REGION()
 
+    CV_Assert(!_src.empty());
+    CV_Assert( _mask.empty() || _mask.type() == CV_8UC1 );
+
     CV_OCL_RUN(OCL_PERFORMANCE_CHECK(_src.isUMat()) && _src.dims() <= 2,
                ocl_meanStdDev(_src, _mean, _sdv, _mask))
 
     Mat src = _src.getMat(), mask = _mask.getMat();
-    CV_Assert( mask.empty() || mask.type() == CV_8UC1 );
 
     CV_OVX_RUN(!ovx::skipSmallImages<VX_KERNEL_MEAN_STDDEV>(src.cols, src.rows),
                openvx_meanStdDev(src, _mean, _sdv, mask))

modules/core/src/rand.cpp

@@ -511,8 +511,8 @@ static RandnScaleFunc randnScaleTab[] =
 void RNG::fill( InputOutputArray _mat, int disttype,
                 InputArray _param1arg, InputArray _param2arg, bool saturateRange )
 {
-    if (_mat.empty())
-        return;
+    CV_Assert(!_mat.empty());
+
     Mat mat = _mat.getMat(), _param1 = _param1arg.getMat(), _param2 = _param2arg.getMat();
     int depth = mat.depth(), cn = mat.channels();
     AutoBuffer<double> _parambuf;