[cfe-users] Trouble understanding reason for Clang error - std::bind/std::function issue

[Adam Nielsen via cfe-users]

> I am having some issues compiling my own code which works with GCC but
> fails using Clang, and I can't work out why.  I am hoping that someone
> here might be able to tell me whether it is an issue with my code or
> a bug in Clang.

I'm still confused by this, but I've been able to produce a small
self-contained example that demonstrates the problem:

=====
  #include <functional>

  bool example_bool(int a, int b)
  {
    return false;
  }

  void example_void(int a, int b)
  {
    return;
  }

  void main2()
  {
    typedef std::function<void(int)> fn;

    // This works
    fn v = std::bind<void>(example_void, std::placeholders::_1, 123);

    // This doesn't work
    fn b = std::bind<void>(example_bool, std::placeholders::_1, 123);
  }
=====

The "fn v" line works, but the "fn b" line fails:

  no known conversion from '__bind_r<void, bool (&)(int, int),
    std::__1::placeholders::__ph<1> &, int>' to
    'std::__1::function<void (int)> &&' for 1st argument

How should I be doing this so that Clang accepts the code?

>   $ clang --version
>   Apple LLVM version 6.0 (clang-600.0.54) (based on LLVM 3.5svn)
>   Target: x86_64-apple-darwin13.4.0

Thanks,
Adam.