C- printf() is writing over my variables - c

Question

I'm working on a practice exercise and it seems printf() is writing over my variable somewhere. I'm working with a structure containing a pointer to an array of pointers to structures so I'm sure I've assigned something slightly wrong somewhere.
int dictionary_add(struct dictionary* d,
const char * const english,
const char * const foreign){
/* ROLE Adds a new wordPair made of strdup copies of the parameter strings
to a dictionary d
RETURNS 0 if everything went fine
PARAMETERS d the dictionary to work with
english string representing the english part of the new wordPair
foreign string representing the foreign part of the new wordPair
*/
//Determine where in the array the wordPair is going.
int location;
location=((d->size)-(d->nbwords))-1;
printf("Adding data to array location: %i\n\n",location);
//Build the wordPair
const struct wordPair newPair={english,foreign};
//Add the wordPair
d->data[0]=&newPair;
//***************This is where the problem shows up***************
printf("Added english:%s\n",d->data[0]->englishWord);
//d->data[0]=&newPair; //When uncommeted, program doesn't crash.
printf("Added english:%s\n",d->data[0]->englishWord);
d->nbwords++;
return 0;
}
How this is called from main():
const char* english=malloc(sizeof(char)*6);
const char* foreign=malloc(sizeof(char)*6);
strcpy(english,"hello");
strcpy(foreign,"holla");
Where the dictionary is created:
struct dictionary *dictionary_build(int size){
/* ROLE Allocate and initialize a new dictionary structure able to accomodate a number of
pairs of words specified by the size parameter
RETURNS Address of new dictionary, if allocation was successfull.
NULL otherwize
PARAMETERS The size of the dictionary to make
*/
struct dictionary *d=malloc(sizeof(struct dictionary));
d->size=size;
d->nbwords=0;
struct wordpair* wordPairs[size]; //create array of pointers to wordpairs
d->data=&wordPairs; //Set pointer to array of pointers to wordpairs
return d;
}
The structures:
struct wordPair {
char* englishWord;
char* foreignWord;
};
struct dictionary {
struct wordPair ** data;
int nbwords;
int size;
};
Thanks in advance for any help. And I'm not opposed to the idea that my entire design misses the point. I can change anything outside of the struct definitions and the expected parameters.

Answer 1

When you do this:
struct wordpair* wordPairs[size];
d->data=&wordPairs;
return d;
}
wordPairs has automatic storage, and its lifetime will end when the function returns. It's undefined behavior to attempt to refer to an object after the end of its life, yet you are retaining a pointer to it within d which you then try to dereference in dictionary_add().
Use something like d->data = malloc(size * sizeof(struct wordpair *)); or similar, instead. Don't forget to check the return from malloc() to determine whether it succeeded, and (usually) to free() everything when you're done.