What happens on malloc0? Does it return NULL or a valid pointer? Depends on the system. If it returns NULL, this program segfaults on the assert.

malloc0.c

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

int main() {
        void* myemptyptr = malloc(0);
        void* myfullptr = malloc(10);
        assert(myemptyptr);
        printf("Empty pointer: %p 10byte Pointer: %p\n", myemptyptr, myfullptr);
        free(myemptyptr);
        free(myfullptr);

        for (int i=0; i<1000; i++) {
                void* newptr = malloc(0);
                void* newcptr = calloc(0, sizeof(char));
                assert(newptr);
                assert(newcptr);
                free(newptr);
                free(newcptr);
        }
}