Type-Safe Generics in C: A Clever Use of Unions

This article presents a technique for implementing type-safe generic data structures in C using unions to associate type information with a generic data structure. The author illustrates the approach with a linked list, showing how macros and unions enable compile-time type checking, avoiding the type-unsafety and code bloat of traditional generic methods. Comparisons are made with `void*` and flexible array member approaches, culminating in a solution that provides compile-time type safety, resulting in compiler errors when incorrect types are added.