C++ using this pointer in constructor initialization list

Question

Is it legal to use this pointer in constructor initialization list in following case? I'm trying to start some background thread with task which is class method. Is it a good approach at all, can I do better? It works with clang (LLVM 3.5), but I'm afraid of undefined behavior.

class SomeClass  {
    public:
        SomeClass();

    private:
        std::thread syncThread;
        void syncTask();
};


SomeClass::SomeClass()
    :syncThread(&SomeClass::syncTask, this) { // is it legal? object is under construction
}