diff --git a/src/base/text_edit.c b/src/base/text_edit.c
index 0f117b859..e3600d632 100644
--- a/src/base/text_edit.c
+++ b/src/base/text_edit.c
@@ -978,7 +978,7 @@ static int text_edit_insert(STB_TEXTEDIT_STRING* str, int pos, STB_TEXTEDIT_CHAR
   uint32_t i = 0;
 
   for (i = 0; i < num; i++) {
-    if (i + 1 < num && TWINS_WCHAR_IS_LINE_BREAK(newtext[i], newtext[i + 1])) {
+    if ((i + 1) < num && (TWINS_WCHAR_IS_LINE_BREAK(newtext[i], newtext[i + 1]))) {
       line_break_num--;
       i++;
     } else if (WCHAR_IS_LINE_BREAK(newtext[i])) {
diff --git a/src/base/widget.c b/src/base/widget.c
index 9a40fdc0e..018653704 100644
--- a/src/base/widget.c
+++ b/src/base/widget.c
@@ -1243,12 +1243,14 @@ static widget_t* widget_lookup_by_type_all(widget_t* widget, const char* type) {
   return_value_if_fail(widget != NULL && type != NULL, NULL);
 
   WIDGET_FOR_EACH_CHILD_BEGIN(widget, iter, i)
-  if (tk_str_eq(iter->vt->type, type)) {
+  if (iter == NULL) {
+    continue;
+  } else if(tk_str_eq(iter->vt->type, type)) {
     return iter;
   } else {
-    iter = widget_lookup_by_type_all(iter, type);
-    if (iter != NULL) {
-      return iter;
+    widget_t* ret = widget_lookup_by_type_all(iter, type);
+    if (ret != NULL) {
+      return ret;
     }
   }
   WIDGET_FOR_EACH_CHILD_END();
diff --git a/src/csv/csv_file_object.c b/src/csv/csv_file_object.c
index 606a5a2c4..2f005a791 100644
--- a/src/csv/csv_file_object.c
+++ b/src/csv/csv_file_object.c
@@ -386,7 +386,6 @@ static ret_t csv_file_object_exec(tk_object_t* obj, const char* name, const char
     o->is_dirty = TRUE;
   } else if (tk_str_ieq(name, TK_OBJECT_CMD_ADD)) {
     if (args != NULL) {
-      return_value_if_fail(args != NULL, RET_FAIL);
       ret = csv_file_append_row(o->csv, args) == RET_OK ? RET_ITEMS_CHANGED : RET_FAIL;
       o->is_dirty = TRUE;
     } else {
diff --git a/src/ext_widgets/mutable_image/mutable_image.c b/src/ext_widgets/mutable_image/mutable_image.c
index 015365b39..c314bc449 100644
--- a/src/ext_widgets/mutable_image/mutable_image.c
+++ b/src/ext_widgets/mutable_image/mutable_image.c
@@ -177,7 +177,7 @@ static ret_t mutable_image_init_impl(widget_t* widget) {
   image_base_init(widget);
   mutable_image->timer_id = widget_add_timer(widget, mutable_image_invalidate, 16);
 
-  if (widget->parent != NULL && widget != NULL) {
+  if (widget != NULL && widget->parent != NULL) {
     mutable_image_on_attach_parent(widget, widget->parent);
   }
   return RET_OK;
diff --git a/staticcheck/cppcheck/run.py b/staticcheck/cppcheck/run.py
index f374c97fc..a8b47b685 100644
--- a/staticcheck/cppcheck/run.py
+++ b/staticcheck/cppcheck/run.py
@@ -3,6 +3,6 @@ import sys
 sys.path.append("../common")
 import awtk_files as awtk;
 
-CPPFLAGS = '-DHAS_STD_MALLOC -DNDEBUG --enable=warning  --enable=performance -DWITH_CPPCHECK '
+CPPFLAGS = '-DHAS_STD_MALLOC -DNDEBUG --enable=warning  --enable=performance -DWITH_CPPCHECK --check-level=exhaustive '
 
 awtk.run('cppcheck', CPPFLAGS, awtk.getCppCheckFiles())