diff --git a/3rdparty/libtiff/tif_dirread.c b/3rdparty/libtiff/tif_dirread.c
index 667a5d9644..a9da79769d 100644
--- a/3rdparty/libtiff/tif_dirread.c
+++ b/3rdparty/libtiff/tif_dirread.c
@@ -1450,14 +1450,14 @@ TIFFFetchShortPair(TIFF* tif, TIFFDirEntry* dir)
 		case TIFF_BYTE:
 		case TIFF_SBYTE:
 			{
-			uint8 v[4];
+            uint8 v[4]={0,0,0,0};
 			return TIFFFetchByteArray(tif, dir, v)
 				&& TIFFSetField(tif, dir->tdir_tag, v[0], v[1]);
 			}
 		case TIFF_SHORT:
 		case TIFF_SSHORT:
 			{
-			uint16 v[2];
+            uint16 v[2]={0,0};
 			return TIFFFetchShortArray(tif, dir, v)
 				&& TIFFSetField(tif, dir->tdir_tag, v[0], v[1]);
 			}
diff --git a/modules/core/src/matrix.cpp b/modules/core/src/matrix.cpp
index e55b0031aa..95b0c4e36f 100644
--- a/modules/core/src/matrix.cpp
+++ b/modules/core/src/matrix.cpp
@@ -2205,7 +2205,7 @@ static void generateCentersPP(const Mat& _data, Mat& _out_centers,
 {
     int i, j, k, dims = _data.cols, N = _data.rows;
     const float* data = _data.ptr<float>(0);
-    int step = (int)(_data.step/sizeof(data[0]));
+    size_t step = _data.step/sizeof(data[0]);
     vector<int> _centers(K);
     int* centers = &_centers[0];
     vector<float> _dist(N*3);