diff --git a/mindspore/lite/micro/coder/opcoders/nnacl/dequant/de_quant.cc b/mindspore/lite/micro/coder/opcoders/nnacl/dequant/de_quant.cc
index 0e3b9a7475..2a23cf8519 100644
--- a/mindspore/lite/micro/coder/opcoders/nnacl/dequant/de_quant.cc
+++ b/mindspore/lite/micro/coder/opcoders/nnacl/dequant/de_quant.cc
@@ -78,7 +78,7 @@ void Dequant::DeQuantFunction(const Tensor *quant_tensor, const std::vector<DeQu
   }
   *de_quant_code << "&" << de_quant_arg_base_str << std::to_string(quant_arg_dims - 1);
   *de_quant_code << "};\n";
-  auto channels = static_cast<size_t>(quant_tensor->Batch());
+  int32_t channels = quant_tensor->Batch();
   std::string quant_tensor_addr_str = "(int8_t *)(" + quant_tensor_addr_ + ")";
   de_quant_code->CodeFunction("DequantData", quant_tensor_addr_str, de_quant_args_name, de_quant_nums, channels,
                               de_quant_buffer_str_);
diff --git a/mindspore/lite/micro/coder/opcoders/nnacl/fp32/transpose_fp32_coder.cc b/mindspore/lite/micro/coder/opcoders/nnacl/fp32/transpose_fp32_coder.cc
index e92aaa2426..069fb7d933 100644
--- a/mindspore/lite/micro/coder/opcoders/nnacl/fp32/transpose_fp32_coder.cc
+++ b/mindspore/lite/micro/coder/opcoders/nnacl/fp32/transpose_fp32_coder.cc
@@ -131,14 +131,19 @@ int TransposeFp32Coder::DoCode(CoderContext *const context) {
   dims_ = output_tensor_->shape().size();
   if (dims_ > MAX_TRANSPOSE_DIM_SIZE) {
     int *dim_size = reinterpret_cast<int *>(malloc(dims_ * sizeof(int)));
-    MS_CHECK_PTR(dim_size);
+    if (dim_size == nullptr) {
+      return RET_NULL_PTR;
+    }
     *(dim_size + dims_ - 1) = 1;
     for (int i = dims_ - 1; i > 0; --i) {
       *(dim_size + i - 1) = *(dim_size + i) * out_shape_[i];
     }
     code.CodeArray("dim_size", dim_size, dims_);
     int *position = reinterpret_cast<int *>(malloc(dims_ * thread_num_ * sizeof(int)));
-    MS_CHECK_PTR(position);
+    if (position == nullptr) {
+      free(dim_size);
+      return RET_NULL_PTR;
+    }
     code.CodeArray("position", position, dims_ * thread_num_);
     code.CodeFunction("TransposeDimsFp32", input_tensor_, output_tensor_, out_shape_, "dim_size", "position",
                       "&trans_param", kDefaultTaskId, thread_num_);
diff --git a/mindspore/lite/micro/coder/opcoders/nnacl/int8/add_int8_coder.cc b/mindspore/lite/micro/coder/opcoders/nnacl/int8/add_int8_coder.cc
index 32f48eb580..066a9de00d 100644
--- a/mindspore/lite/micro/coder/opcoders/nnacl/int8/add_int8_coder.cc
+++ b/mindspore/lite/micro/coder/opcoders/nnacl/int8/add_int8_coder.cc
@@ -53,7 +53,7 @@ int AddInt8Coder::Init() {
   const double twice_max_input_scale = 2 * std::max(in0_scale, in1_scale);
   const double in0_multiplier = in0_scale / twice_max_input_scale;
   const double in1_multiplier = in1_scale / twice_max_input_scale;
-  const double out_multiplier = twice_max_input_scale / ((1 << para_.left_shift_) * out_scale);
+  const double out_multiplier = twice_max_input_scale / ((1 << static_cast<uint32_t>(para_.left_shift_)) * out_scale);
 
   QuantizeMultiplierSmallerThanOne(in0_multiplier, &para_.in0_args_.multiplier_, &para_.in0_args_.left_shift_);
   QuantizeMultiplierSmallerThanOne(in1_multiplier, &para_.in1_args_.multiplier_, &para_.in1_args_.left_shift_);
diff --git a/mindspore/lite/micro/coder/opcoders/nnacl/int8/sub_int8_coder.cc b/mindspore/lite/micro/coder/opcoders/nnacl/int8/sub_int8_coder.cc
index fb9b7f9c14..de327f0cbd 100644
--- a/mindspore/lite/micro/coder/opcoders/nnacl/int8/sub_int8_coder.cc
+++ b/mindspore/lite/micro/coder/opcoders/nnacl/int8/sub_int8_coder.cc
@@ -41,7 +41,7 @@ int SubInt8Coder::Prepare(CoderContext *const context) {
   param_.out_args_.scale_ = output_tensor_->quant_params().front().scale;
   param_.out_args_.zp_ = output_tensor_->quant_params().front().zeroPoint;
 
-  const int left_shift = 20;
+  const uint32_t left_shift = 20;
   const double twice_max_input_scale = 2 * std::max(param_.in0_args_.scale_, param_.in1_args_.scale_);
   const double real_input0_multiplier = param_.in0_args_.scale_ / twice_max_input_scale;
   const double real_input1_multiplier = param_.in1_args_.scale_ / twice_max_input_scale;
@@ -54,10 +54,10 @@ int SubInt8Coder::Prepare(CoderContext *const context) {
   param_.output_activation_min_ = std::numeric_limits<int8_t>::min();
   param_.output_activation_max_ = std::numeric_limits<int8_t>::max();
 
-  int left_shift0 = -param_.input0_shift_ > 0 ? -param_.input0_shift_ : 0;
+  uint32_t left_shift0 = -param_.input0_shift_ > 0 ? -param_.input0_shift_ : 0;
   param_.right_shift0_ = -param_.input0_shift_ > 0 ? 0 : param_.input0_shift_;
 
-  int left_shift1 = -param_.input1_shift_ > 0 ? -param_.input1_shift_ : 0;
+  uint32_t left_shift1 = -param_.input1_shift_ > 0 ? -param_.input1_shift_ : 0;
   param_.right_shift1_ = -param_.input1_shift_ > 0 ? 0 : param_.input1_shift_;
 
   param_.left_shift_out_ = -param_.output_shift_ > 0 ? -param_.output_shift_ : 0;
diff --git a/mindspore/lite/micro/coder/wrapper/int8/conv_init_int8_wrapper.c b/mindspore/lite/micro/coder/wrapper/int8/conv_init_int8_wrapper.c
index 9947c56140..13092890ba 100644
--- a/mindspore/lite/micro/coder/wrapper/int8/conv_init_int8_wrapper.c
+++ b/mindspore/lite/micro/coder/wrapper/int8/conv_init_int8_wrapper.c
@@ -15,7 +15,6 @@
  */
 
 #include "wrapper/int8/conv_init_int8_wrapper.h"
-#include <memory.h>
 #include "nnacl/op_base.h"
 #include "nnacl/int8/matmul_int8.h"
 #include "nnacl/errorcode.h"