diff --git a/modules/core/test/test_io.cpp b/modules/core/test/test_io.cpp
index 09a45fd6a2..431ff43a99 100644
--- a/modules/core/test/test_io.cpp
+++ b/modules/core/test/test_io.cpp
@@ -144,7 +144,11 @@ protected:
 
             depth = cvtest::randInt(rng) % (CV_64F+1);
             cn = cvtest::randInt(rng) % 4 + 1;
-            int sz[] = {cvtest::randInt(rng)%10+1, cvtest::randInt(rng)%10+1, cvtest::randInt(rng)%10+1};
+            int sz[] = {
+                static_cast<int>(cvtest::randInt(rng)%10+1),
+                static_cast<int>(cvtest::randInt(rng)%10+1),
+                static_cast<int>(cvtest::randInt(rng)%10+1),
+            };
             MatND test_mat_nd(3, sz, CV_MAKETYPE(depth, cn));
 
             rng0.fill(test_mat_nd, CV_RAND_UNI, Scalar::all(ranges[depth][0]), Scalar::all(ranges[depth][1]));
@@ -156,8 +160,12 @@ protected:
                 multiply(test_mat_nd, test_mat_scale, test_mat_nd);
             }
 
-            int ssz[] = {cvtest::randInt(rng)%10+1, cvtest::randInt(rng)%10+1,
-                cvtest::randInt(rng)%10+1,cvtest::randInt(rng)%10+1};
+            int ssz[] = {
+                static_cast<int>(cvtest::randInt(rng)%10+1),
+                static_cast<int>(cvtest::randInt(rng)%10+1),
+                static_cast<int>(cvtest::randInt(rng)%10+1),
+                static_cast<int>(cvtest::randInt(rng)%10+1),
+            };
             SparseMat test_sparse_mat = cvTsGetRandomSparseMat(4, ssz, cvtest::randInt(rng)%(CV_64F+1),
                                                                cvtest::randInt(rng) % 10000, 0, 100, rng);