没有发现编译选项有什么区别，如下：
CASE1：link失败的console信息：
make all
make --no-print-directory pre-build
a9-linaro-pre-build-step
' '
make --no-print-directory main-build
'Building target: math_test.elf'
'Invoking: ARM v7 gcc linker'
arm-none-eabi-gcc -mcpu=cortex-a9 -mfpu=vfpv3 -mfloat-abi=hard -Wl,-build-id=none -specs=Xilinx.spec -Wl,-T -Wl,../src/lscript.ld -LE:/****/freeRTOS/export/freeRTOS/sw/freeRTOS/freertos10_xilinx_domain/bsplib/lib -o "math_test.elf" ./src/freertos_hello_world.o -Wl,--start-group,-lxil,-lfreertos,-lgcc,-lc,--end-group
d:/xilinx/vitis/.2/gnu/aarch32/nt/gcc-arm-none-eabi/bin/../lib/gcc/arm-none-eabi/8.2.0/../../../../arm-none-eabi/bin/ld.exe: ./src/freertos_hello_world.o: in function `main':
E:\****\math_test\Debug/../src/freertos_hello_world.c:64: undefined reference to `sqrt'
collect2.exe: error: ld returned 1 exit status
CASE2：使用另外一个xsa创建的工程，link可以通过，同样用到sqrt，以下为console信息：
make all
make --no-print-directory pre-build
a9-linaro-pre-build-step
' '
make --no-print-directory main-build
'Building target: math_test.elf'
'Invoking: ARM v7 gcc linker'
arm-none-eabi-gcc -mcpu=cortex-a9 -mfpu=vfpv3 -mfloat-abi=hard -Wl,-build-id=none -specs=Xilinx.spec -Wl,-T -Wl,../src/lscript.ld -LE:/***/freeRTOS/export/freeRTOS/sw/freeRTOS/freertos10_xilinx_domain/bsplib/lib -o "math_test.elf" ./src/freertos_hello_world.o -Wl,--start-group,-lxil,-lfreertos,-lgcc,-lc,--end-group
'Finished building target: math_test.elf'
