ccs3.3优化编译报错如何解决

程序中函数内有如下语句：

unsigned int  i;

GpioDataRegs.GPBDAT.all = (GpioDataRegs.GPBDAT.all & 0xFFF0FFFF)|0x00080000;
for(i=0;i<100;i++);

采用-o3优化编译，报错如下：

Local\Temp\0118811", ERROR! at line 751: [E5369]
Due to FPU pipeline restriction this instruction is illegal in the 4
delay slots of MOV32 R0H,ACC

I16TOF32 R1H,*+XAR3[AR0] ; |398|

4 Assembly Errors, No Assembly Warnings

补充：

将unsigned int  i ;改写为volatile unsigned int  i;依旧不能解决，这改怎么办呢