diff --git a/tools/sdk/lib/liblwip_gcc.a b/tools/sdk/lib/liblwip_gcc.a
index 4758c769a..0e56b9be7 100644
Binary files a/tools/sdk/lib/liblwip_gcc.a and b/tools/sdk/lib/liblwip_gcc.a differ
diff --git a/tools/sdk/lwip/include/lwip/igmp.h b/tools/sdk/lwip/include/lwip/igmp.h
index c90adcdce..f0c9dea3f 100644
--- a/tools/sdk/lwip/include/lwip/igmp.h
+++ b/tools/sdk/lwip/include/lwip/igmp.h
@@ -96,7 +96,7 @@ void   igmp_input(struct pbuf *p, struct netif *inp, ip_addr_t *dest)ICACHE_FLAS
 err_t  igmp_joingroup(ip_addr_t *ifaddr, ip_addr_t *groupaddr)ICACHE_FLASH_ATTR;
 err_t  igmp_leavegroup(ip_addr_t *ifaddr, ip_addr_t *groupaddr)ICACHE_FLASH_ATTR;
 void   igmp_tmr(void)ICACHE_FLASH_ATTR;
-#define LWIP_RAND()  r_rand()
+#define LWIP_RAND()  os_random()
 #ifdef __cplusplus
 }
 #endif