This is a continuation of https://developer.apple.com/forums/thread/795348 I rambled too much and did not understand the underlaying problem. The problem is that I have a C function in a iOS library. I want to call this C function from a dylib that this library loads on runtime. When running directly from Xcode (either in debug or release mode) this works correctly. However, when the app is uploaded to testflight or distributed for debugging then the function is stripped and a null function pointer exception crashes the app. In the last post it was really hard to explain and I was pressed on time but I've created a minimal reproducible example: https://github.com/ospfranco/dylib_crash The instructions to run and reproduce the crash are on the README.