diff --git a/mace/benchmark/benchmark_model.cc b/mace/benchmark/benchmark_model.cc
index bf4119cb3ffdfbeb5ce1ffb15ea1e5727fa32670..38db846b2a5c651e4dead8357ce1753649f6bd65 100644
--- a/mace/benchmark/benchmark_model.cc
+++ b/mace/benchmark/benchmark_model.cc
@@ -100,6 +100,7 @@ bool RunInference(MaceEngine *engine,
                   std::map<std::string, float*> *output_infos,
                   StatSummarizer *summarizer,
                   int64_t *inference_time_us) {
+  MACE_CHECK_NOTNULL(output_infos);
   RunMetadata run_metadata;
   RunMetadata *run_metadata_ptr = nullptr;
   if (summarizer) {
@@ -144,6 +145,7 @@ bool Run(MaceEngine *engine,
          int64_t sleep_sec,
          int64_t *total_time_us,
          int64_t *actual_num_runs) {
+  MACE_CHECK_NOTNULL(output_infos);
   *total_time_us = 0;
 
   LOG(INFO) << "Running benchmark for max " << num_runs << " iterators, max "
diff --git a/mace/utils/command_line_flags.cc b/mace/utils/command_line_flags.cc
index 38c74bb6c3f154c9c2be9b543384c0aee5af158b..e6b8041248a02ca07e20c62074233b2f23b2d663 100644
--- a/mace/utils/command_line_flags.cc
+++ b/mace/utils/command_line_flags.cc
@@ -13,6 +13,7 @@ namespace mace {
 namespace utils {
 
 bool StringConsume(const std::string &x, std::string *arg) {
+  MACE_CHECK_NOTNULL(arg);
   if ((arg->size() >= x.size()) &&
       (memcmp(arg->data(), x.data(), x.size()) == 0)) {
     *arg = arg->substr(x.size());