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cmemory-leaksmallocfree

Is this malloc/free pair leaking memory?

I'm new to C.

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

void demo() {
    char* s = malloc(10);
    strcpy(s, "foo");
    free(s);
}

int main()
{
    demo();
}

Will this program leak memory with several bytes?

Solution

  • Will this program leak memory with several bytes?

    No.

    free(s) will de-allocate all the memory that was dynamically allocated by char* s = malloc(10); in this example.

    As @Alexander commented: "Is your concern about the last 6 characters of s? (past the end of "foo") Worry not, free() will free the whole allocation of s, regardless of how you used it or what you put in it"

    Good read: What is a memory leak?