Question

Is it possible to determine the size of a C++ class at compile-time?

I seem to remember a template meta-programming method, but I could be mistaken…

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sorry for not being clearer – I want the size to be printed in the build output window

Answer 1

If you really need to to get sizeof(X) in the compiler output, you can use it as a parameter for an incomplete template type:

template<int s> struct Wow;
struct foo {
    int a,b;
};
Wow<sizeof(foo)> wow;

$ g++ -c test.cpp
test.cpp:5: error: aggregate ‘Wow<8> wow’ has incomplete type and cannot be defined