Core file not being overwritten error

Problem

I was dealing with a program that was segfaulting. It was writing a core file on segmentation fault. However, I noticed that if a core file already existed in the directory, the program would not overwrite it on segfault. Only if the existing core file was deleted, then a new one would be created!

Solution

This is due to a well known bug of Apport, the crash reporting service in Ubuntu. It can be disabled as described here. Once disabled, I found that the core file was being overwritten correctly on a new segmentation fault.

Tried with: Apport 2.14.1 and Ubuntu 14.04