Windows下 undefined reference to `memcpy'

发布于 2022-05-26 09:46:43 浏览：670 订阅该版

移植Nano到CA7的一个平台，交叉编译用的ARM GCC，编译通过，但是link的时候提示
```
C:\arm-none-eabi\11.2_2022.02\bin\arm-none-eabi-ld.exe: objs/cmd.o: in function `list_thread':
cmd.c:(.text+0x3fc): undefined reference to `memcpy'
C:\arm-none-eabi\11.2_2022.02\bin\arm-none-eabi-ld.exe: objs/cmd.o: in function `list':
cmd.c:(.text+0xc18): undefined reference to `strncmp'
C:\arm-none-eabi\11.2_2022.02\bin\arm-none-eabi-ld.exe: objs/msh.o: in function `msh_help':
msh.c:(.text+0x68): undefined reference to `strncmp'
```
这个应该是libc.a里面有的。ARM GCC不能主动Link标准库吗？
因此，我在makefile用-L指定libc.a的路径，用-lc 指定文件。依然提示上面的错误。
```
arm-none-eabi-ld -Tlink.lds **-LC:\arm-none-eabi\11.2_2022.02\lib\gcc\arm-none-eabi\11.2.1 -lc** -v -o Hoopoe_Nano.elf objs/context_gcc.o objs/cp15_gcc.o objs/start_gcc.o objs/vector_gcc.o objs/clock.o objs/components.o objs/cpu.o objs/idle.o objs/ipc.o objs/irq.o objs/kservice.o objs/mem.o objs/memheap.o objs/mempool.o objs/object.o objs/scheduler.o objs/slab.o objs/thread.o objs/timer.o objs/cache.o objs/cpu_ca.o objs/gic.o objs/interrupt.o objs/mmu.o objs/pmu.o objs/stack.o objs/trap.o objs/board.o objs/drv_timer.o objs/drv_uart.o objs/hoop.o objs/main.o objs/cmd.o objs/finsh_port.o objs/msh.o objs/shell.o

怀疑windows下-Lwindows路径不对，但是修改了各种网上搜到的形式都不行。

最后，把libc.a跟.o放到一起编译就通过了。不太明白这其中的原因，请求大神帮忙解答。
arm-none-eabi-ld -Tlink.lds -LC:\arm-none-eabi\11.2_2022.02\lib\gcc\arm-none-eabi\11.2.1 -v -o Hoopoe_Nano.elf objs/context_gcc.o objs/cp15_gcc.o objs/start_gcc.o objs/vector_gcc.o objs/clock.o objs/components.o objs/cpu.o objs/idle.o objs/ipc.o objs/irq.o objs/kservice.o objs/mem.o objs/memheap.o objs/mempool.o objs/object.o objs/scheduler.o objs/slab.o objs/thread.o objs/timer.o objs/cache.o objs/cpu_ca.o objs/gic.o objs/interrupt.o objs/mmu.o objs/pmu.o objs/stack.o objs/trap.o objs/board.o objs/drv_timer.o objs/drv_uart.o objs/hoop.o objs/main.o objs/cmd.o objs/finsh_port.o objs/msh.o objs/shell.o **C:\arm-none-eabi\11.2_2022.02\lib\gcc\arm-none-eabi\11.2.1\libc.a**
```