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#### False positive with -Wmaybe-uninitialized

Sometimes on GCC compilers below version 5.1 you may get an -Wmaybe-uninitialized warning when compiling with option -02 on a perfectly valid `boost::optional` usage. For instance in this program:

    #include <boost/optional.hpp>

    boost::optional<int> getitem();

    int main(int argc, const char *[])
    {
      boost::optional<int> a = getitem();
      boost::optional<int> b;

      if (argc > 0)
        b = argc;

      if (a != b)
        return 1;

      return 0;
    }

This is a bug in the compiler. As a workaround (provided in this Stack Overflow question) use the following way of initializing an optional containing no value:

    boost::optional<int> b = boost::make_optional(false, int());

This is obviously redundant, but makes the warning disappear.