How to debug segmentation fault?

Question

It works when, in the loop, I set every element to 0 or to entry_count-1. It works when I set it up so that entry_count is small, and I write it by hand instead of by loop (

Answer 1

That is hard, I used valgrind tools to debug seg-faults and it usually pointed to violations.

Likely your problem is freed memory that you are writing to i.e. sorted_array gets out of scope or gets freed. Adding more code hides this problem as data allocation shifts around.