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C++ ↔ C

Concern	C	C++
Overloading	Manual/ad-hoc	Automatic
Exceptions	-	Stack unwinding
Destructors	Manual cleanup	Automatic via destructors (RAII)
Non-POD types	-	Objects with constructors, vtables, virtual bases
Templates	-	Compile-time code generation

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C++ includes a number of features that don't exist in C with an FFI impact:

Overloading: Overloads become impossible to express because of name mangling

Exceptions: Must catch exceptions at the FFI boundary and convert them to error codes, as escaping exceptions in extern "C" functions constitute undefined behavior

Destructors: C callers won't run destructors; must expose explicit *_destroy() functions

Non-POD types: Must use opaque pointers across the FFI boundary as pass by value does not make sense

Templates: Cannot expose directly; must instantiate explicitly and wrap each specialization

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