Unexpected Segmentation Fault in C++ with std::map and Custom Comparator
I've searched everywhere and can't find a clear answer. I'm currently dealing with a segmentation fault in my C++ application, and I suspect it relates to the use of `std::map` with a custom comparator. I'm working with GCC version 11.2 and trying to store objects of a class that I've implemented. The comparator I wrote is using a member function to compare the objects, but I'm receiving a segmentation fault when trying to insert items into the map. Here’s the minimal example of what I’ve done: ```cpp #include <iostream> #include <map> class MyClass { public: int data; MyClass(int d) : data(d) {} }; struct Compare { bool operator()(const MyClass &a, const MyClass &b) const { return a.data < b.data; } }; int main() { std::map<MyClass, int, Compare> myMap; myMap.insert(std::make_pair(MyClass(1), 100)); // First insertion myMap.insert(std::make_pair(MyClass(2), 200)); // Second insertion return 0; } ``` When I run this code, I get the following behavior: ``` Segmentation fault (core dumped) ``` I have ensured that my objects are copyable and that the comparator is consistent, but I am unsure if I'm missing something regarding the lifetime of the `MyClass` objects or the way I am using `std::map`. I've also tried to create the objects on the heap, but that didn't resolve the scenario either. Any insights on what might be causing this segmentation fault or how I can properly implement this with a custom comparator would be greatly appreciated. Is there a best practice for using custom comparators with `std::map` that I might be overlooking? What's the best practice here? I've been using Cpp for about a year now.