Capturing a static variable by reference in a C++11 lambda

Why are you even trying to capture bar? It’s static. You don’t need to capture it at all. Only automatic variables need capturing. Clang throws a hard error on your code, not just a warning. And if you simply remove the &bar from your lambda capture, then the code works perfectly.

#include <iostream>

int foo() {
    static int bar;
    return [] () { return bar++; } (); // lambda capturing by reference
}

int main (int argc, char* argv[]) {
    std::cout << foo() << std::endl;
    std::cout << foo() << std::endl;
    std::cout << foo() << std::endl;
    return 0;
}

prints

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