Memory allocation for same string literals

Question

Consider this code:

int main(void)
{
    printf("%s", "the string");
    printf("%s", "the string");
}

Is there any standard saying that the program memory will be allocated only once for "the string" and not twice (or any other number of times, depending on how many times the literal is used)? When I examine the output elf file of my program, for such a case I can only find the string occurring just once and I am trying to figure out whether this is a rule, or is it compiler dependent.

Does this answer your question? [Same strings in array have same memory address](https://stackoverflow.com/questions/26433563/same-strings-in-array-have-same-memory-address) — Harith, Mar 18 '23 at 08:51
If could be once or twice or none at all (a serious of `puchar()` statements.) — chux - Reinstate Monica, Mar 18 '23 at 09:00
"is it compiler dependent." --> rather than look at compilers output, consider reviewing the C spec. — chux - Reinstate Monica, Mar 18 '23 at 09:02

score 1 · Accepted Answer · answered Mar 18 '23 at 09:04

Modern compilers and more recently link time optimizers automatically share string literals across modules or the whole program. There is no need for any particular indication in the code, but the programmer should not rely on this to always happen as some platforms or debugging modes might alter this behavior, that is indeed compiler dependent.

Memory allocation for same string literals

1 Answers1