Function Fix

function.patch

diff --git a/include/functional b/include/functional
index 3c9f5a7..539a708 100644
--- a/include/functional
+++ b/include/functional
@@ -1475,13 +1475,25 @@ __func<_Fp, _Alloc, _Rp(_ArgTypes...)>::target_type() const _NOEXCEPT
 
 }  // __function
 
+typedef typename aligned_storage<3*sizeof(void*)>::type _SmallFuncBuf;
+
+template <class _Tp>
+  struct _IsSmallFunc
+    : public integral_constant<bool
+        , sizeof(_Tp) <= 3*sizeof(void*)
+          && alignment_of<_SmallFuncBuf>::value
+             % alignment_of<_Tp>::value == 0
+          && is_nothrow_copy_constructible<_Tp>::value
+        >
+  {};
+
 template<class _Rp, class ..._ArgTypes>
 class _LIBCPP_TYPE_VIS_ONLY function<_Rp(_ArgTypes...)>
     : public __function::__maybe_derive_from_unary_function<_Rp(_ArgTypes...)>,
       public __function::__maybe_derive_from_binary_function<_Rp(_ArgTypes...)>
 {
     typedef __function::__base<_Rp(_ArgTypes...)> __base;
-    typename aligned_storage<3*sizeof(void*)>::type __buf_;
+    _SmallFuncBuf __buf_;
     __base* __f_;
 
     template <class _Fp, bool = !is_same<_Fp, function>::value &&
@@ -1651,7 +1663,7 @@ function<_Rp(_ArgTypes...)>::function(_Fp __f,
     if (__function::__not_null(__f))
     {
         typedef __function::__func<_Fp, allocator<_Fp>, _Rp(_ArgTypes...)> _FF;
-        if (sizeof(_FF) <= sizeof(__buf_) && is_nothrow_copy_constructible<_Fp>::value)
+        if (_IsSmallFunc<_Fp>::value)
         {
             __f_ = (__base*)&__buf_;
             ::new (__f_) _FF(_VSTD::move(__f));
@@ -1680,8 +1692,7 @@ function<_Rp(_ArgTypes...)>::function(allocator_arg_t, const _Alloc& __a0, _Fp _
         typedef __function::__func<_Fp, _Alloc, _Rp(_ArgTypes...)> _FF;
         typedef typename __rebind_alloc_helper<__alloc_traits, _FF>::type _Ap;
         _Ap __a(__a0);
-        if (sizeof(_FF) <= sizeof(__buf_) && 
-            is_nothrow_copy_constructible<_Fp>::value && is_nothrow_copy_constructible<_Ap>::value)
+        if (_IsSmallFunc<_Fp>::value && is_nothrow_copy_constructible<_Ap>::value)
         {
             __f_ = (__base*)&__buf_;
             ::new (__f_) _FF(_VSTD::move(__f), _Alloc(__a));
@@ -1769,7 +1780,7 @@ function<_Rp(_ArgTypes...)>::swap(function& __f) _NOEXCEPT
 {
     if (__f_ == (__base*)&__buf_ && __f.__f_ == (__base*)&__f.__buf_)
     {
-        typename aligned_storage<sizeof(__buf_)>::type __tempbuf;
+        _SmallFuncBuf __tempbuf;
         __base* __t = (__base*)&__tempbuf;
         __f_->__clone(__t);
         __f_->destroy();