Optimization with GCC

Question

Recently I was wondering if it is possible to compile with some flag optimization, avoid copying two arrays for the section .rodata? Thus, memory addresses would be equal, example

const char str[7] = "string";

const char str1[7] = "string";


int printf(const char *format, ...);

int main(void) {

     if(str == str1) 
         printf("Endereços de memória iguais");

     return 0;

}

So in this example above, is it possible somehow for the compiler to use the same memory addresses?

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EDIT:

It doesn’t make much sense anyway no, kkkk, it was just a matter of curiosity anyway, I tried to see some flags optimization, but without success.

#include <stdio.h>

void main(void) {

     char *str1 = "string";
     char *str2 = "string";

     if(str == str2) puts("Igual");
}

In the above example, the compiler places the string pointer literal str1 in the section .rodata and uses the same string, or is the same address for the pointer str2. That’s why I wanted to know if you can simulate this by doing array. I read the Manpage of GCC, but I found nothing relevant in that sense, but anyway thank you very much for your reply.

Answer 1

Yes, it is possible, although this code doesn’t seem to make much sense:

#include <stdio.h>

int main(void) {
    const char str[7] = "string";
    const char *str1 = str;
    if(str == str1) printf("Endereços de memória iguais");
}

Behold working in the ideone. And in the repl it.. Also put on the Github for future reference.

I know you expected another answer, but another one doesn’t make sense. In C if you want an optimization, optimize, don’t wait for the compiler to do it for you.