usart中printf函数使用gcc编译出现几处报错

bumbdong

如题，在使用eclipse编译一个串口工程的时候，出现以下报错：

Building target: qq.elf

Invoking: Cross ARM C++ Linker

arm-none-eabi-g++ -mcpu=cortex-m3 -mthumb -Og -fmessage-length=0 -fsigned-char -ffunction-sections -fdata-sections -ffreestanding -fno-move-loop-invariants -Wunused -Wuninitialized -Wall -Wextra -Wmissing-declarations -Wconversion -Wpointer-arith -Wpadded -Wshadow -Wlogical-op -Waggregate-return -Wfloat-equal  -g3 -T mem.ld -T libs.ld -T sections.ld -nostartfiles -Xlinker --gc-sections -L"../ldscripts" -Wl,-Map,"qq.map" --specs=nano.specs -o "qq.elf"  ./system/src/stm32f1-stdperiph/misc.o ./system/src/stm32f1-stdperiph/stm32f10x_gpio.o ./system/src/stm32f1-stdperiph/stm32f10x_rcc.o ./system/src/stm32f1-stdperiph/stm32f10x_usart.o  ./system/src/newlib/_cxx.o ./system/src/newlib/_exit.o ./system/src/newlib/_sbrk.o ./system/src/newlib/_startup.o ./system/src/newlib/_syscalls.o ./system/src/newlib/assert.o  ./system/src/diag/Trace.o ./system/src/diag/trace_impl.o  ./system/src/cortexm/_initialize_hardware.o ./system/src/cortexm/_reset_hardware.o ./system/src/cortexm/exception_handlers.o  ./system/src/cmsis/system_stm32f10x.o ./system/src/cmsis/vectors_stm32f10x.o  ./src/delay.o ./src/key.o ./src/led.o ./src/main.o ./src/sys.o ./src/usart.o   

/usr/local/gcc-arm-none-eabi-5_3-2016q1/bin/../lib/gcc/arm-none-eabi/5.3.1/../../../../arm-none-eabi/lib/armv7-m/libg_nano.a(lib_a-writer.o): In function `_write_r':

writer.c.text._write_r+0x10): undefined reference to `_write'

/usr/local/gcc-arm-none-eabi-5_3-2016q1/bin/../lib/gcc/arm-none-eabi/5.3.1/../../../../arm-none-eabi/lib/armv7-m/libg_nano.a(lib_a-closer.o): In function `_close_r':

closer.c.text._close_r+0xc): undefined reference to `_close'

/usr/local/gcc-arm-none-eabi-5_3-2016q1/bin/../lib/gcc/arm-none-eabi/5.3.1/../../../../arm-none-eabi/lib/armv7-m/libg_nano.a(lib_a-lseekr.o): In function `_lseek_r':

lseekr.c.text._lseek_r+0x10): undefined reference to `_lseek'

/usr/local/gcc-arm-none-eabi-5_3-2016q1/bin/../lib/gcc/arm-none-eabi/5.3.1/../../../../arm-none-eabi/lib/armv7-m/libg_nano.a(lib_a-readr.o): In function `_read_r':

readr.c.text._read_r+0x10): undefined reference to `_read'

/usr/local/gcc-arm-none-eabi-5_3-2016q1/bin/../lib/gcc/arm-none-eabi/5.3.1/../../../../arm-none-eabi/lib/armv7-m/libg_nano.a(lib_a-fstatr.o): In function `_fstat_r':

fstatr.c.text._fstat_r+0xe): undefined reference to `_fstat'

/usr/local/gcc-arm-none-eabi-5_3-2016q1/bin/../lib/gcc/arm-none-eabi/5.3.1/../../../../arm-none-eabi/lib/armv7-m/libg_nano.a(lib_a-isattyr.o): In function `_isatty_r':

isattyr.c.text._isatty_r+0xc): undefined reference to `_isatty'

collect2: error: ld returned 1 exit status

make: *** [qq.elf] Error 1

_write、`_close、_lseek、_read、_fstat、_isatty这些函数应该重定义还是应该怎么办？

求救原子哥！@正点原子 @八度空间

bumbdong

还是自己搞好了啊。。。

正点原子

帮顶