ucos移植到STM32上一直报错

我已添加ucos-ii.h和os_cpu_a.asm,编译时显示如下错误,请大家帮忙看一下问题出在哪里？
ucos.axf: Error: L6218E: Undefined symbol OSPrioCur (referred from os_cpu_a.o).
ucos.axf: Error: L6218E: Undefined symbol OSPrioHighRdy (referred from os_cpu_a.o).
ucos.axf: Error: L6218E: Undefined symbol OSRunning (referred from os_cpu_a.o).
ucos.axf: Error: L6218E: Undefined symbol OSTCBCur (referred from os_cpu_a.o).
ucos.axf: Error: L6218E: Undefined symbol OSTCBHighRdy (referred from os_cpu_a.o).
ucos.axf: Error: L6218E: Undefined symbol OSIntExit (referred from os_cpu_c.o).
ucos.axf: Error: L6218E: Undefined symbol OSIntNesting (referred from os_cpu_c.o).
ucos.axf: Error: L6218E: Undefined symbol OSTimeTick (referred from os_cpu_c.o).
ucos.axf: Error: L6218E: Undefined symbol OS_CPU_SysTickClkFreq (referred from os_cpu_c.o).
ucos.axf: Error: L6218E: Undefined symbol OSLockNesting (referred from os_task.o).
ucos.axf: Error: L6218E: Undefined symbol OSRdyGrp (referred from os_task.o).
ucos.axf: Error: L6218E: Undefined symbol OSRdyTbl (referred from os_task.o).
ucos.axf: Error: L6218E: Undefined symbol OSTCBFreeList (referred from os_task.o).
ucos.axf: Error: L6218E: Undefined symbol OSTCBList (referred from os_task.o).
ucos.axf: Error: L6218E: Undefined symbol OSTCBPrioTbl (referred from os_task.o).
ucos.axf: Error: L6218E: Undefined symbol OSTaskCtr (referred from os_task.o).
ucos.axf: Error: L6218E: Undefined symbol OS_Dummy (referred from os_task.o).
ucos.axf: Error: L6218E: Undefined symbol OS_MemCopy (referred from os_task.o).
ucos.axf: Error: L6218E: Undefined symbol OS_Sched (referred from os_task.o).
ucos.axf: Error: L6218E: Undefined symbol OS_StrCopy (referred from os_task.o).
ucos.axf: Error: L6218E: Undefined symbol OS_StrLen (referred from os_task.o).
ucos.axf: Error: L6218E: Undefined symbol OS_TCBInit (referred from os_task.o).
ucos.axf: Error: L6218E: Undefined symbol OSTime (referred from os_time.o).
Target not created