CodeSourcery ARM交叉编译

Question

编译一个简单的test.c：

#include <stdio.h>

void main() {
  printf("Hello World!\n");
  while(1);
}

使用CodeSourcery的arm-none-eabi-gcc我收到了以下错误：

arm-none-eabi-gcc -static test.c -o mytest

/opt/Sourcery_CodeBench_Lite_for_ARM_EABI/bin/../lib/gcc/arm-none-eabi/4.8.1/../../../../arm-none-eabi/bin/ld: warning: cannot find entry symbol _start; defaulting to 00008018
/opt/Sourcery_CodeBench_Lite_for_ARM_EABI/bin/../lib/gcc/arm-none-eabi/4.8.1/../../../../arm-none-eabi/lib/libc.a(lib_a-sbrkr.o): In function `_sbrk_r':
sbrkr.c:(.text+0x18): undefined reference to `_sbrk'
/opt/Sourcery_CodeBench_Lite_for_ARM_EABI/bin/../lib/gcc/arm-none-eabi/4.8.1/../../../../arm-none-eabi/lib/libc.a(lib_a-writer.o): In function `_write_r':
writer.c:(.text+0x20): undefined reference to `_write'
/opt/Sourcery_CodeBench_Lite_for_ARM_EABI/bin/../lib/gcc/arm-none-eabi/4.8.1/../../../../arm-none-eabi/lib/libc.a(lib_a-closer.o): In function `_close_r':
closer.c:(.text+0x18): undefined reference to `_close'
/opt/Sourcery_CodeBench_Lite_for_ARM_EABI/bin/../lib/gcc/arm-none-eabi/4.8.1/../../../../arm-none-eabi/lib/libc.a(lib_a-fstatr.o): In function `_fstat_r':
fstatr.c:(.text+0x1c): undefined reference to `_fstat'
/opt/Sourcery_CodeBench_Lite_for_ARM_EABI/bin/../lib/gcc/arm-none-eabi/4.8.1/../../../../arm-none-eabi/lib/libc.a(lib_a-isattyr.o): In function `_isatty_r':
isattyr.c:(.text+0x18): undefined reference to `_isatty'
/opt/Sourcery_CodeBench_Lite_for_ARM_EABI/bin/../lib/gcc/arm-none-eabi/4.8.1/../../../../arm-none-eabi/lib/libc.a(lib_a-lseekr.o): In function `_lseek_r':
lseekr.c:(.text+0x20): undefined reference to `_lseek'
/opt/Sourcery_CodeBench_Lite_for_ARM_EABI/bin/../lib/gcc/arm-none-eabi/4.8.1/../../../../arm-none-eabi/lib/libc.a(lib_a-readr.o): In function `_read_r':
readr.c:(.text+0x20): undefined reference to `_read'
collect2: error: ld returned 1 exit status

但如果我使用我的Ubuntu（12.04 LTS 32位）的手臂gcc：

arm-linux-gnueabi-gcc -static -o mytest test.c

arm-linux-gnueabi-gcc -v
Using built-in specs.
COLLECT_GCC=arm-linux-gnueabi-gcc
COLLECT_LTO_WRAPPER=/usr/lib/gcc/arm-linux-gnueabi/4.6/lto-wrapper
Target: arm-linux-gnueabi
Configured with: ../src/configure -v --with-pkgversion='Ubuntu/Linaro 4.6.3-1ubuntu5' --with-bugurl=file:///usr/share/doc/gcc-4.6/README.Bugs --enable-languages=c,c++,fortran,objc,obj-c++ --prefix=/usr --program-suffix=-4.6 --enable-shared --enable-linker-build-id --with-system-zlib --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --with-gxx-include-dir=/usr/arm-linux-gnueabi/include/c++/4.6.3 --libdir=/usr/lib --enable-nls --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-gnu-unique-object --enable-plugin --enable-objc-gc --enable-multilib --disable-sjlj-exceptions --with-arch=armv7-a --with-float=softfp --with-fpu=vfpv3-d16 --with-mode=thumb --disable-werror --enable-checking=release --build=i686-linux-gnu --host=i686-linux-gnu --target=arm-linux-gnueabi --program-prefix=arm-linux-gnueabi- --includedir=/usr/arm-linux-gnueabi/include --with-headers=/usr/arm-linux-gnueabi/include --with-libs=/usr/arm-linux-gnueabi/lib
Thread model: posix
gcc version 4.6.3 (Ubuntu/Linaro 4.6.3-1ubuntu5) 

我没有生成输出文件的错误。

谁能解释一下？

我最近的参考（但我仍然没有成功）：

使用eclipse在C项目上的链接器错误

Answer 1

arm-none-eabi-gcc是裸机臂的编译器。 即在没有操作系统的臂处理器上运行，或者在您自己的操作系统上运行。 该编译器包含newlib C库，它将为您提供大部分标准C库，但您必须提供低级实现（例如，printf（）某处实际打印，内存管理，文件系统，如果您需要它）。 简而言之，您需要自己动手执行处理器，C运行时并加载生成的代码（参见例如此问题））

arm-linux-gnueabi-gcc是一个用于定位linux on arm的编译器，这是一个使用熟悉的glibc C库和头文件生成在linux上运行的可执行文件的工具链。