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I've compiled cpuid2.s to cpuid2.o by as cpuid2.s -o cpuid2.o -gstabs

Firstly I linked it by ld -o cpuid2 cpuid2.o -lc but a message says ./cpuid2:no such file or directory when I executed it (which is due to having not use dynamic linker, says the book)

So I linked it by ld -dynamic-linker /lib64/ld-linux-x86-64.so.2 -o cpuid2 cpuid2.o -lc then executed it, however a SegmentationFault occurs: when gdb it step by step, gdb says printf.c:no such file or directory at the line call printf

is it because I haven't install C's library(however I can run simple C programs with function in stdio.h)?

#cpuid2.s View the CPUID Vendor ID string using C library calls
.code32
.section .data
output:
   .asciz "The processor Vendor ID is '%s'\n"
.section .bss
   .lcomm buffer, 12
.section .text
.globl _start
_start:
   movl $0, %eax
   cpuid
   movl $buffer, %edi
   movl %ebx, (%edi)
   movl %edx, 4(%edi)
   movl %ecx, 8(%edi)
   pushl $buffer
   pushl $output
   call printf
   addl $8, %esp
   pushl $0
   call exit
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    is it because I haven't install C's library Close. It is because you don't have the source code of the C library. Normally you don't need it. You can also assume that the C library implementation for printf is very likely correct. Commented Feb 21, 2022 at 9:08
  • Please do not post pictures of code. Code is text and should be included directly into the question. Just copy&paste it into the question and put a line containint 3 byckticks above and below it as I did with my edit Commented Feb 21, 2022 at 9:17
  • @Gerhardh Many thanks, I can't simply step into C library, haha. And I've post the code the way you said and it looks much better. However there's still a SegmentationFalult in the line second to last("pushl $0"), and I can't understand why Commented Feb 21, 2022 at 10:09
  • I think you are using the wrong dynamic loader for your 32-bit code. Commented Feb 21, 2022 at 11:02
  • 2
    The 12-character cpuid string is not null-terminated, so you will need to either make the buffer longer (it is in BSS so the extra characters will be initialized to 0), or use %.12s to print no more than 12 characters. Commented Feb 21, 2022 at 11:08
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