Thread: Segmantation fault in inline assembly! Any one please help....

Hi

I'm new to linux programming. Please help me to solve this error

Linux version: Ubuntu
Compiler: GCC
Program: String concatenation using inline assembly.

Code:

#include<stdio.h>
#include<string.h>
 
 static inline  char * asm_str_concat(char *d, char *s1, char *s2)
{
   int rsrc1, rdest,rsrc2;
 
   __asm__ __volatile__(   

    "1:lodsb\n\t;"
    "stosb\n\t;"
    "testb %%al,%%al\n\t;"
    "jne 1b;"
 
    "dec %%di;"
    "movl %%ecx,%0;"
 
    "2:lodsb\n\t;"
    "stosb\n\t;"
    "testb %%al,%%al\n\t;"
    "jne 2b;"
    : "=&S" (rsrc2), "=&D" (rdest),"=a"(s2)
    : "0" (s2),"1" (d),"c" (s1)
    );
              
    return d;
  }  
 
 
 int main(int argc,char *argv[])
{
    char dest2[512];
    char *src1;
    char *src2;
    char *d2;
    src1=argv[1];
    src2=argv[2];
   
    printf("%d",*argv[1]);  
    printf("%s",src1);
    printf("%s\n",src2);
   
    d2 = asm_str_concat(dest2, src2,src1 );
  
    printf("%s\n",dest2);

    return 0;
   
  } 

Error: Segmentation fault (core dumped) after giving 2nd string.

The program works fine if I give the input strings in main program directly.

But if I try to get the inputs from command line its getting 1st input and 2nd input strings then showing segmentation fault. So there shud be a problem in passing the strings to inline program. i'm not able to figure it out.

Please help me....

Thanks in advance