Segfault when using pointer to a function with incompatible signature in C
I recently switched to I'm migrating some code and I'm writing unit tests and I'm working on a personal project and I've been struggling with this for a few days now and could really use some help. I'm working with a segmentation fault when trying to use a pointer to a function that has an incompatible signature. My goal is to implement a callback mechanism for sorting functions, but I'm not sure if my function pointers are correctly defined. Here’s the code I’m working with: ```c #include <stdio.h> #include <stdlib.h> // Function prototype for comparison int compare_integers(const void *a, const void *b); // Sorting function that accepts a comparison function void sort_array(int *arr, size_t size, int (*cmp)(const void*, const void*)) { qsort(arr, size, sizeof(int), cmp); } // Comparison function definition int compare_integers(const void *a, const void *b) { return (*(int*)a - *(int*)b); } int main() { int array[] = {5, 2, 8, 1, 4}; size_t size = sizeof(array) / sizeof(array[0]); sort_array(array, size, compare_integers); for (size_t i = 0; i < size; i++) { printf("%d ", array[i]); } return 0; } ``` However, when I run this code, I sometimes get a segmentation fault. It seems to work fine for small arrays but crashes intermittently for larger ones. I have checked the array bounds, and they seem fine. I suspect it might be related to the function pointer signature or how I’m using `qsort`. I’ve also tried the following variations: 1. Changing the comparison function to accept integers directly instead of pointers. 2. Adding debug prints inside the `compare_integers` function to check the values of `a` and `b` before dereferencing them. 3. I ensured that the array is not modified while sorting. Here’s the behavior message I receive: `Segmentation fault (core dumped)`. Could there be an scenario with how I've set up the function pointer, or is there something else I might be missing? This is part of a larger web app I'm building. What am I doing wrong? I'd really appreciate any guidance on this. I'm working in a Ubuntu 20.04 environment. My development environment is Linux. Cheers for any assistance! I'm coming from a different tech stack and learning C. What am I doing wrong?