diff --git a/src/kservice.c b/src/kservice.c
index 7ed05b6651..40040f7885 100644
--- a/src/kservice.c
+++ b/src/kservice.c
@@ -1238,7 +1238,7 @@ RTM_EXPORT(rt_kprintf);
  *
  * @return the allocated memory block on successful, otherwise returns RT_NULL
  */
-void *rt_malloc_align(rt_size_t size, rt_size_t align)
+RT_WEAK void *rt_malloc_align(rt_size_t size, rt_size_t align)
 {
     void *ptr;
     void *align_ptr;
@@ -1284,7 +1284,7 @@ RTM_EXPORT(rt_malloc_align);
  *
  * @param ptr the memory block pointer
  */
-void rt_free_align(void *ptr)
+RT_WEAK void rt_free_align(void *ptr)
 {
     void *real_ptr;
 
diff --git a/src/memheap.c b/src/memheap.c
index d3ad6d2c36..779988e92f 100644
--- a/src/memheap.c
+++ b/src/memheap.c
@@ -757,6 +757,8 @@ static struct rt_memheap _heap;
 
 void rt_system_heap_init(void *begin_addr, void *end_addr)
 {
+    RT_ASSERT((rt_uint32_t)end_addr > (rt_uint32_t)begin_addr);
+
     /* initialize a default heap in the system */
     rt_memheap_init(&_heap,
                     "heap",