Better explanation of error.

src/list.c

@@ -31,8 +31,7 @@ void addToList(List *l, mpz_t n) {
 	if(unlikely(l->end == l->size)) {
 		l->size += BLOCK_SIZE;
 		if(unlikely(l->size == 0)) {
-			fprintf(stderr,
-					"Size has reached limit of `long long int' type!\n");
+			fprintf(stderr, "`l->size' has overflowed!\n");
 			exit(1);
 		}
 		void *tmp = realloc(l->list, sizeof(mpz_t) * l->size);