Pass parameters to std::thread wrapper

Question

I want to implement a small thread wrapper that provides the information if a thread is still active, or if the thread has finished its work. For this I need to pass the functio

Answer 1

The following is simple, elegant, and to my knowledge the most-correct of all current answers (see below):

template < class Function, class... Args >
ManagedThread::ManagedThread( Function&& fn, Args&&... args ) :
    mActive(false),
    mThread(
        [this]( auto&& fn2, auto&&... args2 ) -> void {
            mActive = true;
            fn2(std::forward(args2)...);
            mActive = false;
        },
        std::forward(fn), std::forward(args)...
    )
{}

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The answer by DeiDei has a subtle but important flaw: the lambda takes the stack variables by reference, so if the thread starts, and tries to use, the stack variables after the constructor returns, you can get a stack-use-after-free error. Indeed, compiling with -fsanitize=address is typically sufficient to demonstrate the problem.

The answer by O'Neill does not work when e.g. any arguments are lvalues, and is a bit clunky.

The answer by jotik is close, but does not work when the arguments are lvalues either, nor if they are member functions.