diff --git a/components/shell/src/cmds/vfs_shellcmd.c b/components/shell/src/cmds/vfs_shellcmd.c
index d4cfe3c3..d2087686 100755
--- a/components/shell/src/cmds/vfs_shellcmd.c
+++ b/components/shell/src/cmds/vfs_shellcmd.c
@@ -259,7 +259,7 @@ int OsShellCmdCat(int argc, const char **argv)
     char *fullpath = NULL;
     int ret;
     CHAR buf[CAT_BUF_SIZE];
-    size_t size;
+    ssize_t size;
 
     char *shellWorkingDirectory = OsShellGetWorkingDirtectory();
 
@@ -283,7 +283,7 @@ int OsShellCmdCat(int argc, const char **argv)
     do {
         (void)memset_s(buf, sizeof(buf), 0, CAT_BUF_SIZE);
         size = read(fd, buf, CAT_BUF_SIZE - 1);
-        if ((int)size < 0) {
+        if (size < 0) {
             free(fullpath);
             close(fd);
             return -1;
diff --git a/kal/posix/src/mqueue.c b/kal/posix/src/mqueue.c
index b5728825..67622f83 100644
--- a/kal/posix/src/mqueue.c
+++ b/kal/posix/src/mqueue.c
@@ -384,7 +384,7 @@ int OsMqGetAttr(mqd_t personal, struct mq_attr *mqAttr)
 
     mqueueCB = privateMqPersonal->mq_posixdes;
     mqAttr->mq_maxmsg = mqueueCB->mqcb->queueLen;
-    mqAttr->mq_msgsize = mqueueCB->mqcb->queueSize - sizeof(UINT32);
+    mqAttr->mq_msgsize = (long)(mqueueCB->mqcb->queueSize - sizeof(UINT32));
     mqAttr->mq_curmsgs = mqueueCB->mqcb->readWriteableCnt[OS_QUEUE_READ];
     mqAttr->mq_flags = privateMqPersonal->mq_flags;
     (VOID)pthread_mutex_unlock(&g_mqueueMutex);
diff --git a/kal/posix/src/time.c b/kal/posix/src/time.c
index cdd93d8a..b9c910ea 100644
--- a/kal/posix/src/time.c
+++ b/kal/posix/src/time.c
@@ -251,7 +251,7 @@ STATIC VOID OsGetHwTime(struct timespec *hwTime)
                      (cycle % OS_SYS_CLOCK) * OS_SYS_NS_PER_SECOND / OS_SYS_CLOCK;
 
     hwTime->tv_sec = (time_t)(nowNsec / OS_SYS_NS_PER_SECOND);
-    hwTime->tv_nsec = nowNsec % OS_SYS_NS_PER_SECOND;
+    hwTime->tv_nsec = (long)(nowNsec % OS_SYS_NS_PER_SECOND);
 }
 
 STATIC VOID OsGetRealTime(struct timespec *realTime)