fix iScan C++ problems, test=develop (#33274)

paddle/fluid/operators/math/concat_test.cc

@@ -437,6 +437,8 @@ void TestConcatMain() {
   ConcatCase2<DeviceContext, Place>(context);
   ConcatCase3<DeviceContext, Place>(context);
   ConcatCase4<DeviceContext, Place>(context);
+
+  delete context;
 }
 
 TEST(math, concat) {

paddle/fluid/operators/math/math_function_test.cc

@@ -208,6 +208,7 @@ void GemvTest(int m, int n, bool trans) {
       ASSERT_FLOAT_EQ(data_c[i], sum);
     }
   }
+  delete cpu_place;
 }
 
 TEST(math_function, gemv) {
@@ -274,6 +275,7 @@ void GemmWarpTest(int m, int n, int k, T alpha, T beta) {
   for (int i = 0; i < mat_c_mkl.numel(); ++i) {
     EXPECT_FLOAT_EQ(CREF[i], CMKL[i]);
   }
+  delete cpu_place;
 }
 
 TEST(math_function, gemm_warp) {

paddle/fluid/operators/math/vol2col_test.cc

@@ -116,6 +116,9 @@ void testVol2col() {
   for (int i = 0; i < 12; ++i) {
     EXPECT_EQ(in_ptr[i], col_2_vol[i]);
   }
+
+  delete place;
+  delete context;
 }
 
 TEST(math, vol2col) {

paddle/fluid/operators/scatter_test.cc

@@ -54,4 +54,6 @@ TEST(scatter, ScatterUpdate) {
     EXPECT_EQ(output.data<float>()[i], static_cast<float>(i - 4));
   for (size_t i = 8; i < 16; ++i) EXPECT_EQ(p_output[i], 0.0f);
   for (size_t i = 8; i < 16; ++i) EXPECT_EQ(output.data<float>()[i], 0.0f);
+
+  delete cpu_place;
 }