Arraylist in C not working

Question

I am currently writing a program to implement an arraylist (or dynamic array) in C. Hmm... I think I have 70 - 80% done with it, however, I found a serious problem with my c

Answer 1

At first glance: in arraylist_add you declare new_data as a local variable. When you pass that to arraylist_set_data_collection, it passes the pointer to this data. However, once arraylist_add returns to main, new_data is out of scope, and is therefore no longer valid.

Consider doing a deep copy and handling the memory manually with malloc and free.