gcc - 在 Ubuntu 11.10 中使用 gcc 链接错误

Question

我正在尝试用 C 语言编译并运行一个简单的“Hello World”程序，但出现了一个奇怪的错误一些 C stdlib 函数的多重定义

.c 文件是:

#include <stdio.h>
#include <stdlib.h>

int main(int argc, char **argv) {

  printf("hello world\n");
  return 0;
}

我用来编译和创建可执行文件的命令是:

gcc -Werror -Wall src/main.c -o bin/m.o
gcc -Werror -Wall bin/m.o -o bin/m

编译部分进展顺利，但在第二个命令中，我调用了 GCC 链接器创建可执行文件时出现以下错误:

bin/m.o: In function `_fini':
(.fini+0x0): multiple definition of `_fini'
/usr/lib/gcc/x86_64-linux-gnu/4.6.1/../../../x86_64-linux-gnu/crti.o:(.fini+0x0): first defined here
bin/m.o: In function `__data_start':
(.data+0x0): multiple definition of `__data_start'
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 0 has invalid symbol index 10
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 1 has invalid symbol index 11
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 2 has invalid symbol index 2
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 3 has invalid symbol index 2
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 4 has invalid symbol index 10
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 5 has invalid symbol index 12
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 6 has invalid symbol index 12
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 7 has invalid symbol index 12
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 8 has invalid symbol index 2
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 9 has invalid symbol index 2
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 10 has invalid symbol index 11
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 11 has invalid symbol index 12
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 12 has invalid symbol index 12
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 13 has invalid symbol index 12
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 14 has invalid symbol index 12
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 15 has invalid symbol index 12
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 16 has invalid symbol index 12
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 17 has invalid symbol index 12
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 18 has invalid symbol index 12
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 19 has invalid symbol index 12
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_info): relocation 20 has invalid symbol index 19
/usr/lib/gcc/x86_64-linux-gnu/4.6.1/../../../x86_64-linux-gnu/crt1.o:(.data+0x0): first defined here
bin/m.o: In function `__data_start':
(.data+0x8): multiple definition of `__dso_handle'
/usr/lib/gcc/x86_64-linux-gnu/4.6.1/crtbegin.o:(.data+0x0): first defined here
bin/m.o:(.rodata+0x0): multiple definition of `_IO_stdin_used'
/usr/lib/gcc/x86_64-linux-gnu/4.6.1/../../../x86_64-linux-gnu/crt1.o:             (.rodata.cst4+0x0): first defined here
bin/m.o: In function `_start':
(.text+0x0): multiple definition of `_start'
/usr/bin/ld: /usr/lib/debug/usr/lib/x86_64-linux-gnu/crt1.o(.debug_line): relocation 0 has invalid symbol index 2
/usr/lib/gcc/x86_64-linux-gnu/4.6.1/../../../x86_64-linux-gnu/crt1.o:/build/buildd    /eglibc-2.13/csu/../sysdeps/x86_64/elf/start.S:109: first defined here
bin/m.o: In function `_init':
(.init+0x0): multiple definition of `_init'
/usr/lib/gcc/x86_64-linux-gnu/4.6.1/../../../x86_64-linux-gnu/crti.o:(.init+0x0): first     defined here
/usr/lib/gcc/x86_64-linux-gnu/4.6.1/crtend.o:(.dtors+0x0): multiple definition of     `__DTOR_END__'
bin/m.o:(.dtors+0x8): first defined here
/usr/bin/ld: error in bin/m.o(.eh_frame); no .eh_frame_hdr table will be created.
collect2: ld returned 1 exit status

顺便说一下，当我使用 bash 执行前缀运行 m.o 文件时，它工作得很好

从来没有用 C 或任何东西编程，我正在尝试开始，但这阻碍了我

Answer 1

您在编译步骤中需要一个-c，否则您的m.o对象将是一个完全链接的可执行文件。示例:

gcc -Werror -Wall -c src/main.c -o bin/m.o
gcc -Werror -Wall bin/m.o -o bin/m

如果您的程序不仅仅由单个翻译单元组成，那么差异将立即显而易见。例如，如果您有 file1.c 和 file2.c:

gcc -c file1.c -o file1.o
gcc -c file2.c -o file2.o
gcc file1.o file2.o -o app

是正确的，而如果你有:

gcc file1.c -o file1.o
gcc file2.c -o file2.o
gcc file1.o file2.o -o app

在到达最终链接阶段之前，第一行和第二行都会失败，因为它们会丢失符号。