龙芯1c编译时报错LFN work area cannot be used in

AS build\drivers\selfboot_gcc.o
CC build\drivers\touch.o
drivers\net\synopGMAC.c: In function 'eth_rx_irq':
drivers\net\synopGMAC.c:807:9: warning: implicit declaration of function 'memcpy' [-Wimplicit-function-declaration]
         memcpy(mac_addr0, dev->dev_addr, 6);
         ^
drivers\net\synopGMAC.c: In function 'rt_hw_eth_init':
drivers\net\synopGMAC.c:900:5: warning: implicit declaration of function 'memset' [-Wimplicit-function-declaration]
     memset(ð_dev, 0, sizeof(eth_dev));
     ^
CC build\kernel\components\dfs\filesystems\devfs\devfs.o
CC build\kernel\components\dfs\filesystems\elmfat\dfs_elm.o
CC build\kernel\components\dfs\filesystems\elmfat\ff.o
CC build\kernel\components\dfs\filesystems\elmfat\ffunicode.o
CC build\kernel\components\dfs\src\dfs.o
F:\RT-THREAD\rt-thread\components\dfs\filesystems\elmfat\ff.c:240:2: error: #error Static LFN work area cannot be used in thread-safe configuration
 #error Static LFN work area cannot be used in thread-safe configurationStatic LFN work area cannot be used in thread-safe configuration
  ^
scons: *** [build\kernel\components\dfs\filesystems\elmfat\ff.o] Error 1
scons: building terminated because of errors.