2 files changed, 1093 insertions, 0 deletions

diff --git a/deskutils/kmail/files/patch-agents_unifiedmailboxagent_boost__optional.h b/deskutils/kmail/files/patch-agents_unifiedmailboxagent_boost__optional.h
new file mode 100644
index 000000000000..5e6e08be5f76
--- /dev/null
+++ b/deskutils/kmail/files/patch-agents_unifiedmailboxagent_boost__optional.h
@@ -0,0 +1,1082 @@
+Copyright (C) 2011-2016 Andrzej Krzemienski
+
+Distributed under the Boost Software License, Version 1.0
+(see accompanying file LICENSE_1_0.txt or a copy at
+http://www.boost.org/LICENSE_1_0.txt)
+
+The idea and interface is based on Boost.Optional library
+authored by Fernando Luis Cacciola Carballal
+
+Home at https://github.com/akrzemi1/Optional
+
+
+--- agents/unifiedmailboxagent/boost_optional.h.orig	2018-12-29 21:08:10 UTC
++++ agents/unifiedmailboxagent/boost_optional.h
+@@ -0,0 +1,1067 @@
++// Copyright (C) 2011 - 2012 Andrzej Krzemienski.
++//
++// Use, modification, and distribution is subject to the Boost Software
++// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
++// http://www.boost.org/LICENSE_1_0.txt)
++//
++// The idea and interface is based on Boost.Optional library
++// authored by Fernando Luis Cacciola Carballal
++
++# ifndef ___OPTIONAL_HPP___
++# define ___OPTIONAL_HPP___
++
++# include <utility>
++# include <type_traits>
++# include <initializer_list>
++# include <cassert>
++# include <functional>
++# include <string>
++# include <stdexcept>
++
++# define TR2_OPTIONAL_REQUIRES(...) typename enable_if<__VA_ARGS__::value, bool>::type = false
++
++# if defined __GNUC__ // NOTE: GNUC is also defined for Clang
++#   if (__GNUC__ == 4) && (__GNUC_MINOR__ >= 8)
++#     define TR2_OPTIONAL_GCC_4_8_AND_HIGHER___
++#   elif (__GNUC__ > 4)
++#     define TR2_OPTIONAL_GCC_4_8_AND_HIGHER___
++#   endif
++#
++#   if (__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)
++#     define TR2_OPTIONAL_GCC_4_7_AND_HIGHER___
++#   elif (__GNUC__ > 4)
++#     define TR2_OPTIONAL_GCC_4_7_AND_HIGHER___
++#   endif
++#
++#   if (__GNUC__ == 4) && (__GNUC_MINOR__ == 8) && (__GNUC_PATCHLEVEL__ >= 1)
++#     define TR2_OPTIONAL_GCC_4_8_1_AND_HIGHER___
++#   elif (__GNUC__ == 4) && (__GNUC_MINOR__ >= 9)
++#     define TR2_OPTIONAL_GCC_4_8_1_AND_HIGHER___
++#   elif (__GNUC__ > 4)
++#     define TR2_OPTIONAL_GCC_4_8_1_AND_HIGHER___
++#   endif
++# endif
++#
++# if defined __clang_major__
++#   if (__clang_major__ == 3 && __clang_minor__ >= 5)
++#     define TR2_OPTIONAL_CLANG_3_5_AND_HIGHTER_
++#   elif (__clang_major__ > 3)
++#     define TR2_OPTIONAL_CLANG_3_5_AND_HIGHTER_
++#   endif
++#   if defined TR2_OPTIONAL_CLANG_3_5_AND_HIGHTER_
++#     define TR2_OPTIONAL_CLANG_3_4_2_AND_HIGHER_
++#   elif (__clang_major__ == 3 && __clang_minor__ == 4 && __clang_patchlevel__ >= 2)
++#     define TR2_OPTIONAL_CLANG_3_4_2_AND_HIGHER_
++#   endif
++# endif
++#
++# if defined _MSC_VER
++#   if (_MSC_VER >= 1900)
++#     define TR2_OPTIONAL_MSVC_2015_AND_HIGHER___
++#   endif
++# endif
++
++# if defined __clang__
++#   if (__clang_major__ > 2) || (__clang_major__ == 2) && (__clang_minor__ >= 9)
++#     define OPTIONAL_HAS_THIS_RVALUE_REFS 1
++#   else
++#     define OPTIONAL_HAS_THIS_RVALUE_REFS 0
++#   endif
++# elif defined TR2_OPTIONAL_GCC_4_8_1_AND_HIGHER___
++#   define OPTIONAL_HAS_THIS_RVALUE_REFS 1
++# elif defined TR2_OPTIONAL_MSVC_2015_AND_HIGHER___
++#   define OPTIONAL_HAS_THIS_RVALUE_REFS 1
++# else
++#   define OPTIONAL_HAS_THIS_RVALUE_REFS 0
++# endif
++
++
++# if defined TR2_OPTIONAL_GCC_4_8_1_AND_HIGHER___
++#   define OPTIONAL_HAS_CONSTEXPR_INIT_LIST 1
++#   define OPTIONAL_CONSTEXPR_INIT_LIST constexpr
++# else
++#   define OPTIONAL_HAS_CONSTEXPR_INIT_LIST 0
++#   define OPTIONAL_CONSTEXPR_INIT_LIST
++# endif
++
++# if defined TR2_OPTIONAL_CLANG_3_5_AND_HIGHTER_ && (defined __cplusplus) && (__cplusplus != 201103L)
++#   define OPTIONAL_HAS_MOVE_ACCESSORS 1
++# else
++#   define OPTIONAL_HAS_MOVE_ACCESSORS 0
++# endif
++
++# // In C++11 constexpr implies const, so we need to make non-const members also non-constexpr
++# if (defined __cplusplus) && (__cplusplus == 201103L)
++#   define OPTIONAL_MUTABLE_CONSTEXPR
++# else
++#   define OPTIONAL_MUTABLE_CONSTEXPR constexpr
++# endif
++
++namespace std{
++
++namespace experimental{
++
++// BEGIN workaround for missing is_trivially_destructible
++# if defined TR2_OPTIONAL_GCC_4_8_AND_HIGHER___
++    // leave it: it is already there
++# elif defined TR2_OPTIONAL_CLANG_3_4_2_AND_HIGHER_
++    // leave it: it is already there
++# elif defined TR2_OPTIONAL_MSVC_2015_AND_HIGHER___
++    // leave it: it is already there
++# elif defined TR2_OPTIONAL_DISABLE_EMULATION_OF_TYPE_TRAITS
++    // leave it: the user doesn't want it
++# else
++	template <typename T>
++	using is_trivially_destructible = std::has_trivial_destructor<T>;
++# endif
++// END workaround for missing is_trivially_destructible
++
++# if (defined TR2_OPTIONAL_GCC_4_7_AND_HIGHER___)
++    // leave it; our metafunctions are already defined.
++# elif defined TR2_OPTIONAL_CLANG_3_4_2_AND_HIGHER_
++    // leave it; our metafunctions are already defined.
++# elif defined TR2_OPTIONAL_MSVC_2015_AND_HIGHER___
++    // leave it: it is already there
++# elif defined TR2_OPTIONAL_DISABLE_EMULATION_OF_TYPE_TRAITS
++    // leave it: the user doesn't want it
++# else
++
++
++// workaround for missing traits in GCC and CLANG
++template <class T>
++struct is_nothrow_move_constructible
++{
++  constexpr static bool value = std::is_nothrow_constructible<T, T&&>::value;
++};
++
++
++template <class T, class U>
++struct is_assignable
++{
++  template <class X, class Y>
++  constexpr static bool has_assign(...) { return false; }
++
++  template <class X, class Y, size_t S = sizeof((std::declval<X>() = std::declval<Y>(), true)) >
++  // the comma operator is necessary for the cases where operator= returns void
++  constexpr static bool has_assign(bool) { return true; }
++
++  constexpr static bool value = has_assign<T, U>(true);
++};
++
++
++template <class T>
++struct is_nothrow_move_assignable
++{
++  template <class X, bool has_any_move_assign>
++  struct has_nothrow_move_assign {
++    constexpr static bool value = false;
++  };
++
++  template <class X>
++  struct has_nothrow_move_assign<X, true> {
++    constexpr static bool value = noexcept( std::declval<X&>() = std::declval<X&&>() );
++  };
++
++  constexpr static bool value = has_nothrow_move_assign<T, is_assignable<T&, T&&>::value>::value;
++};
++// end workaround
++
++
++# endif
++
++
++
++// 20.5.4, optional for object types
++template <class T> class optional;
++
++// 20.5.5, optional for lvalue reference types
++template <class T> class optional<T&>;
++
++
++// workaround: std utility functions aren't constexpr yet
++template <class T> inline constexpr T&& constexpr_forward(typename std::remove_reference<T>::type& t) noexcept
++{
++  return static_cast<T&&>(t);
++}
++
++template <class T> inline constexpr T&& constexpr_forward(typename std::remove_reference<T>::type&& t) noexcept
++{
++    static_assert(!std::is_lvalue_reference<T>::value, "!!");
++    return static_cast<T&&>(t);
++}
++
++template <class T> inline constexpr typename std::remove_reference<T>::type&& constexpr_move(T&& t) noexcept
++{
++    return static_cast<typename std::remove_reference<T>::type&&>(t);
++}
++
++
++#if defined NDEBUG
++# define TR2_OPTIONAL_ASSERTED_EXPRESSION(CHECK, EXPR) (EXPR)
++#else
++# define TR2_OPTIONAL_ASSERTED_EXPRESSION(CHECK, EXPR) ((CHECK) ? (EXPR) : ([]{assert(!#CHECK);}(), (EXPR)))
++#endif
++
++
++namespace detail_
++{
++
++// static_addressof: a constexpr version of addressof
++template <typename T>
++struct has_overloaded_addressof
++{
++  template <class X>
++  constexpr static bool has_overload(...) { return false; }
++  
++  template <class X, size_t S = sizeof(std::declval<X&>().operator&()) >
++  constexpr static bool has_overload(bool) { return true; }
++
++  constexpr static bool value = has_overload<T>(true);
++};
++
++template <typename T, TR2_OPTIONAL_REQUIRES(!has_overloaded_addressof<T>)>
++constexpr T* static_addressof(T& ref)
++{
++  return &ref;
++}
++
++template <typename T, TR2_OPTIONAL_REQUIRES(has_overloaded_addressof<T>)>
++T* static_addressof(T& ref)
++{
++  return std::addressof(ref);
++}
++
++
++// the call to convert<A>(b) has return type A and converts b to type A iff b decltype(b) is implicitly convertible to A  
++template <class U>
++constexpr U convert(U v) { return v; }
++  
++
++namespace swap_ns
++{
++  using std::swap;
++    
++  template <class T>
++  void adl_swap(T& t, T& u) noexcept(noexcept(swap(t, u)))
++  {
++    swap(t, u);
++  }
++
++} // namespace swap_ns
++
++} // namespace detail
++
++
++constexpr struct trivial_init_t{} trivial_init{};
++
++
++// 20.5.6, In-place construction
++constexpr struct in_place_t{} in_place{};
++
++
++// 20.5.7, Disengaged state indicator
++struct nullopt_t
++{
++  struct init{};
++  constexpr explicit nullopt_t(init){}
++};
++constexpr nullopt_t nullopt{nullopt_t::init()};
++
++
++// 20.5.8, class bad_optional_access
++class bad_optional_access : public logic_error {
++public:
++  explicit bad_optional_access(const string& what_arg) : logic_error{what_arg} {}
++  explicit bad_optional_access(const char* what_arg) : logic_error{what_arg} {}
++};
++
++
++template <class T>
++union storage_t
++{
++  unsigned char dummy_;
++  T value_;
++
++  constexpr storage_t( trivial_init_t ) noexcept : dummy_() {};
++
++  template <class... Args>
++  constexpr storage_t( Args&&... args ) : value_(constexpr_forward<Args>(args)...) {}
++
++  ~storage_t(){}
++};
++
++
++template <class T>
++union constexpr_storage_t
++{
++    unsigned char dummy_;
++    T value_;
++
++    constexpr constexpr_storage_t( trivial_init_t ) noexcept : dummy_() {};
++
++    template <class... Args>
++    constexpr constexpr_storage_t( Args&&... args ) : value_(constexpr_forward<Args>(args)...) {}
++
++    ~constexpr_storage_t() = default;
++};
++
++
++template <class T>
++struct optional_base
++{
++    bool init_;
++    storage_t<T> storage_;
++
++    constexpr optional_base() noexcept : init_(false), storage_(trivial_init) {};
++
++    explicit constexpr optional_base(const T& v) : init_(true), storage_(v) {}
++
++    explicit constexpr optional_base(T&& v) : init_(true), storage_(constexpr_move(v)) {}
++
++    template <class... Args> explicit optional_base(in_place_t, Args&&... args)
++        : init_(true), storage_(constexpr_forward<Args>(args)...) {}
++
++    template <class U, class... Args, TR2_OPTIONAL_REQUIRES(is_constructible<T, std::initializer_list<U>>)>
++    explicit optional_base(in_place_t, std::initializer_list<U> il, Args&&... args)
++        : init_(true), storage_(il, std::forward<Args>(args)...) {}
++
++    ~optional_base() { if (init_) storage_.value_.T::~T(); }
++};
++
++
++template <class T>
++struct constexpr_optional_base
++{
++    bool init_;
++    constexpr_storage_t<T> storage_;
++
++    constexpr constexpr_optional_base() noexcept : init_(false), storage_(trivial_init) {};
++
++    explicit constexpr constexpr_optional_base(const T& v) : init_(true), storage_(v) {}
++
++    explicit constexpr constexpr_optional_base(T&& v) : init_(true), storage_(constexpr_move(v)) {}
++
++    template <class... Args> explicit constexpr constexpr_optional_base(in_place_t, Args&&... args)
++      : init_(true), storage_(constexpr_forward<Args>(args)...) {}
++
++    template <class U, class... Args, TR2_OPTIONAL_REQUIRES(is_constructible<T, std::initializer_list<U>>)>
++    OPTIONAL_CONSTEXPR_INIT_LIST explicit constexpr_optional_base(in_place_t, std::initializer_list<U> il, Args&&... args)
++      : init_(true), storage_(il, std::forward<Args>(args)...) {}
++
++    ~constexpr_optional_base() = default;
++};
++
++template <class T>
++using OptionalBase = typename std::conditional<
++    is_trivially_destructible<T>::value,                          // if possible
++    constexpr_optional_base<typename std::remove_const<T>::type>, // use base with trivial destructor
++    optional_base<typename std::remove_const<T>::type>
++>::type;
++
++
++
++template <class T>
++class optional : private OptionalBase<T>
++{
++  static_assert( !std::is_same<typename std::decay<T>::type, nullopt_t>::value, "bad T" );
++  static_assert( !std::is_same<typename std::decay<T>::type, in_place_t>::value, "bad T" );
++  
++
++  constexpr bool initialized() const noexcept { return OptionalBase<T>::init_; }
++  typename std::remove_const<T>::type* dataptr() {  return std::addressof(OptionalBase<T>::storage_.value_); }
++  constexpr const T* dataptr() const { return detail_::static_addressof(OptionalBase<T>::storage_.value_); }
++  
++# if OPTIONAL_HAS_THIS_RVALUE_REFS == 1
++  constexpr const T& contained_val() const& { return OptionalBase<T>::storage_.value_; }
++#   if OPTIONAL_HAS_MOVE_ACCESSORS == 1
++  OPTIONAL_MUTABLE_CONSTEXPR T&& contained_val() && { return std::move(OptionalBase<T>::storage_.value_); }
++  OPTIONAL_MUTABLE_CONSTEXPR T& contained_val() & { return OptionalBase<T>::storage_.value_; }
++#   else
++  T& contained_val() & { return OptionalBase<T>::storage_.value_; }
++  T&& contained_val() && { return std::move(OptionalBase<T>::storage_.value_); }
++#   endif
++# else
++  constexpr const T& contained_val() const { return OptionalBase<T>::storage_.value_; }
++  T& contained_val() { return OptionalBase<T>::storage_.value_; }
++# endif
++
++  void clear() noexcept {
++    if (initialized()) dataptr()->T::~T();
++    OptionalBase<T>::init_ = false;
++  }
++  
++  template <class... Args>
++  void initialize(Args&&... args) noexcept(noexcept(T(std::forward<Args>(args)...)))
++  {
++    assert(!OptionalBase<T>::init_);
++    ::new (static_cast<void*>(dataptr())) T(std::forward<Args>(args)...);
++    OptionalBase<T>::init_ = true;
++  }
++
++  template <class U, class... Args>
++  void initialize(std::initializer_list<U> il, Args&&... args) noexcept(noexcept(T(il, std::forward<Args>(args)...)))
++  {
++    assert(!OptionalBase<T>::init_);
++    ::new (static_cast<void*>(dataptr())) T(il, std::forward<Args>(args)...);
++    OptionalBase<T>::init_ = true;
++  }
++
++public:
++  typedef T value_type;
++
++  // 20.5.5.1, constructors
++  constexpr optional() noexcept : OptionalBase<T>()  {};
++  constexpr optional(nullopt_t) noexcept : OptionalBase<T>() {};
++
++  optional(const optional& rhs)
++  : OptionalBase<T>()
++  {
++    if (rhs.initialized()) {
++        ::new (static_cast<void*>(dataptr())) T(*rhs);
++        OptionalBase<T>::init_ = true;
++    }
++  }
++
++  optional(optional&& rhs) noexcept(is_nothrow_move_constructible<T>::value)
++  : OptionalBase<T>()
++  {
++    if (rhs.initialized()) {
++        ::new (static_cast<void*>(dataptr())) T(std::move(*rhs));
++        OptionalBase<T>::init_ = true;
++    }
++  }
++
++  constexpr optional(const T& v) : OptionalBase<T>(v) {}
++
++  constexpr optional(T&& v) : OptionalBase<T>(constexpr_move(v)) {}
++
++  template <class... Args>
++  explicit constexpr optional(in_place_t, Args&&... args)
++  : OptionalBase<T>(in_place_t{}, constexpr_forward<Args>(args)...) {}
++
++  template <class U, class... Args, TR2_OPTIONAL_REQUIRES(is_constructible<T, std::initializer_list<U>>)>
++  OPTIONAL_CONSTEXPR_INIT_LIST explicit optional(in_place_t, std::initializer_list<U> il, Args&&... args)
++  : OptionalBase<T>(in_place_t{}, il, constexpr_forward<Args>(args)...) {}
++
++  // 20.5.4.2, Destructor
++  ~optional() = default;
++
++  // 20.5.4.3, assignment
++  optional& operator=(nullopt_t) noexcept
++  {
++    clear();
++    return *this;
++  }
++  
++  optional& operator=(const optional& rhs)
++  {
++    if      (initialized() == true  && rhs.initialized() == false) clear();
++    else if (initialized() == false && rhs.initialized() == true)  initialize(*rhs);
++    else if (initialized() == true  && rhs.initialized() == true)  contained_val() = *rhs;
++    return *this;
++  }
++  
++  optional& operator=(optional&& rhs)
++  noexcept(is_nothrow_move_assignable<T>::value && is_nothrow_move_constructible<T>::value)
++  {
++    if      (initialized() == true  && rhs.initialized() == false) clear();
++    else if (initialized() == false && rhs.initialized() == true)  initialize(std::move(*rhs));
++    else if (initialized() == true  && rhs.initialized() == true)  contained_val() = std::move(*rhs);
++    return *this;
++  }
++
++  template <class U>
++  auto operator=(U&& v)
++  -> typename enable_if
++  <
++    is_same<typename decay<U>::type, T>::value,
++    optional&
++  >::type
++  {
++    if (initialized()) { contained_val() = std::forward<U>(v); }
++    else               { initialize(std::forward<U>(v));  }
++    return *this;
++  }
++  
++  
++  template <class... Args>
++  void emplace(Args&&... args)
++  {
++    clear();
++    initialize(std::forward<Args>(args)...);
++  }
++  
++  template <class U, class... Args>
++  void emplace(initializer_list<U> il, Args&&... args)
++  {
++    clear();
++    initialize<U, Args...>(il, std::forward<Args>(args)...);
++  }
++  
++  // 20.5.4.4, Swap
++  void swap(optional<T>& rhs) noexcept(is_nothrow_move_constructible<T>::value
++                                       && noexcept(detail_::swap_ns::adl_swap(declval<T&>(), declval<T&>())))
++  {
++    if      (initialized() == true  && rhs.initialized() == false) { rhs.initialize(std::move(**this)); clear(); }
++    else if (initialized() == false && rhs.initialized() == true)  { initialize(std::move(*rhs)); rhs.clear(); }
++    else if (initialized() == true  && rhs.initialized() == true)  { using std::swap; swap(**this, *rhs); }
++  }
++
++  // 20.5.4.5, Observers
++  
++  explicit constexpr operator bool() const noexcept { return initialized(); }
++  constexpr bool has_value() const noexcept { return initialized(); }
++  
++  constexpr T const* operator ->() const {
++    return TR2_OPTIONAL_ASSERTED_EXPRESSION(initialized(), dataptr());
++  }
++  
++# if OPTIONAL_HAS_MOVE_ACCESSORS == 1
++
++  OPTIONAL_MUTABLE_CONSTEXPR T* operator ->() {
++    assert (initialized());
++    return dataptr();
++  }
++  
++  constexpr T const& operator *() const& {
++    return TR2_OPTIONAL_ASSERTED_EXPRESSION(initialized(), contained_val());
++  }
++  
++  OPTIONAL_MUTABLE_CONSTEXPR T& operator *() & {
++    assert (initialized());
++    return contained_val();
++  }
++  
++  OPTIONAL_MUTABLE_CONSTEXPR T&& operator *() && {
++    assert (initialized());
++    return constexpr_move(contained_val());
++  }
++
++  constexpr T const& value() const& {
++    return initialized() ? contained_val() : (throw bad_optional_access("bad optional access"), contained_val());
++  }
++  
++  OPTIONAL_MUTABLE_CONSTEXPR T& value() & {
++    return initialized() ? contained_val() : (throw bad_optional_access("bad optional access"), contained_val());
++  }
++  
++  OPTIONAL_MUTABLE_CONSTEXPR T&& value() && {
++    if (!initialized()) throw bad_optional_access("bad optional access");
++	return std::move(contained_val());
++  }
++  
++# else
++
++  T* operator ->() {
++    assert (initialized());
++    return dataptr();
++  }
++  
++  constexpr T const& operator *() const {
++    return TR2_OPTIONAL_ASSERTED_EXPRESSION(initialized(), contained_val());
++  }
++  
++  T& operator *() {
++    assert (initialized());
++    return contained_val();
++  }
++  
++  constexpr T const& value() const {
++    return initialized() ? contained_val() : (throw bad_optional_access("bad optional access"), contained_val());
++  }
++  
++  T& value() {
++    return initialized() ? contained_val() : (throw bad_optional_access("bad optional access"), contained_val());
++  }
++  
++# endif
++  
++# if OPTIONAL_HAS_THIS_RVALUE_REFS == 1
++
++  template <class V>
++  constexpr T value_or(V&& v) const&
++  {
++    return *this ? **this : detail_::convert<T>(constexpr_forward<V>(v));
++  }
++  
++#   if OPTIONAL_HAS_MOVE_ACCESSORS == 1
++
++  template <class V>
++  OPTIONAL_MUTABLE_CONSTEXPR T value_or(V&& v) &&
++  {
++    return *this ? constexpr_move(const_cast<optional<T>&>(*this).contained_val()) : detail_::convert<T>(constexpr_forward<V>(v));
++  }
++
++#   else
++ 
++  template <class V>
++  T value_or(V&& v) &&
++  {
++    return *this ? constexpr_move(const_cast<optional<T>&>(*this).contained_val()) : detail_::convert<T>(constexpr_forward<V>(v));
++  }
++  
++#   endif
++  
++# else
++  
++  template <class V>
++  constexpr T value_or(V&& v) const
++  {
++    return *this ? **this : detail_::convert<T>(constexpr_forward<V>(v));
++  }
++
++# endif
++
++  // 20.6.3.6, modifiers
++  void reset() noexcept { clear(); }
++};
++
++
++template <class T>
++class optional<T&>
++{
++  static_assert( !std::is_same<T, nullopt_t>::value, "bad T" );
++  static_assert( !std::is_same<T, in_place_t>::value, "bad T" );
++  T* ref;
++  
++public:
++
++  // 20.5.5.1, construction/destruction
++  constexpr optional() noexcept : ref(nullptr) {}
++  
++  constexpr optional(nullopt_t) noexcept : ref(nullptr) {}
++   
++  constexpr optional(T& v) noexcept : ref(detail_::static_addressof(v)) {}
++  
++  optional(T&&) = delete;
++  
++  constexpr optional(const optional& rhs) noexcept : ref(rhs.ref) {}
++  
++  explicit constexpr optional(in_place_t, T& v) noexcept : ref(detail_::static_addressof(v)) {}
++  
++  explicit optional(in_place_t, T&&) = delete;
++  
++  ~optional() = default;
++  
++  // 20.5.5.2, mutation
++  optional& operator=(nullopt_t) noexcept {
++    ref = nullptr;
++    return *this;
++  }
++  
++  // optional& operator=(const optional& rhs) noexcept {
++    // ref = rhs.ref;
++    // return *this;
++  // }
++  
++  // optional& operator=(optional&& rhs) noexcept {
++    // ref = rhs.ref;
++    // return *this;
++  // }
++  
++  template <typename U>
++  auto operator=(U&& rhs) noexcept
++  -> typename enable_if
++  <
++    is_same<typename decay<U>::type, optional<T&>>::value,
++    optional&
++  >::type
++  {
++    ref = rhs.ref;
++    return *this;
++  }
++  
++  template <typename U>
++  auto operator=(U&& rhs) noexcept
++  -> typename enable_if
++  <
++    !is_same<typename decay<U>::type, optional<T&>>::value,
++    optional&
++  >::type
++  = delete;
++  
++  void emplace(T& v) noexcept {
++    ref = detail_::static_addressof(v);
++  }
++  
++  void emplace(T&&) = delete;
++  
++  
++  void swap(optional<T&>& rhs) noexcept
++  {
++    std::swap(ref, rhs.ref);
++  }
++    
++  // 20.5.5.3, observers
++  constexpr T* operator->() const {
++    return TR2_OPTIONAL_ASSERTED_EXPRESSION(ref, ref);
++  }
++  
++  constexpr T& operator*() const {
++    return TR2_OPTIONAL_ASSERTED_EXPRESSION(ref, *ref);
++  }
++  
++  constexpr T& value() const {
++    return ref ? *ref : (throw bad_optional_access("bad optional access"), *ref);
++  }
++  
++  explicit constexpr operator bool() const noexcept {
++    return ref != nullptr;
++  }
++ 
++  constexpr bool has_value() const noexcept {
++    return ref != nullptr;
++  }
++  
++  template <class V>
++  constexpr typename decay<T>::type value_or(V&& v) const
++  {
++    return *this ? **this : detail_::convert<typename decay<T>::type>(constexpr_forward<V>(v));
++  }
++
++  // x.x.x.x, modifiers
++  void reset() noexcept { ref = nullptr; }
++};
++
++
++template <class T>
++class optional<T&&>
++{
++  static_assert( sizeof(T) == 0, "optional rvalue references disallowed" );
++};
++
++
++// 20.5.8, Relational operators
++template <class T> constexpr bool operator==(const optional<T>& x, const optional<T>& y)
++{
++  return bool(x) != bool(y) ? false : bool(x) == false ? true : *x == *y;
++}
++
++template <class T> constexpr bool operator!=(const optional<T>& x, const optional<T>& y)
++{
++  return !(x == y);
++}
++
++template <class T> constexpr bool operator<(const optional<T>& x, const optional<T>& y)
++{
++  return (!y) ? false : (!x) ? true : *x < *y;
++}
++
++template <class T> constexpr bool operator>(const optional<T>& x, const optional<T>& y)
++{
++  return (y < x);
++}
++
++template <class T> constexpr bool operator<=(const optional<T>& x, const optional<T>& y)
++{
++  return !(y < x);
++}
++
++template <class T> constexpr bool operator>=(const optional<T>& x, const optional<T>& y)
++{
++  return !(x < y);
++}
++
++
++// 20.5.9, Comparison with nullopt
++template <class T> constexpr bool operator==(const optional<T>& x, nullopt_t) noexcept
++{
++  return (!x);
++}
++
++template <class T> constexpr bool operator==(nullopt_t, const optional<T>& x) noexcept
++{
++  return (!x);
++}
++
++template <class T> constexpr bool operator!=(const optional<T>& x, nullopt_t) noexcept
++{
++  return bool(x);
++}
++
++template <class T> constexpr bool operator!=(nullopt_t, const optional<T>& x) noexcept
++{
++  return bool(x);
++}
++
++template <class T> constexpr bool operator<(const optional<T>&, nullopt_t) noexcept
++{
++  return false;
++}
++
++template <class T> constexpr bool operator<(nullopt_t, const optional<T>& x) noexcept
++{
++  return bool(x);
++}
++
++template <class T> constexpr bool operator<=(const optional<T>& x, nullopt_t) noexcept
++{
++  return (!x);
++}
++
++template <class T> constexpr bool operator<=(nullopt_t, const optional<T>&) noexcept
++{
++  return true;
++}
++
++template <class T> constexpr bool operator>(const optional<T>& x, nullopt_t) noexcept
++{
++  return bool(x);
++}
++
++template <class T> constexpr bool operator>(nullopt_t, const optional<T>&) noexcept
++{
++  return false;
++}
++
++template <class T> constexpr bool operator>=(const optional<T>&, nullopt_t) noexcept
++{
++  return true;
++}
++
++template <class T> constexpr bool operator>=(nullopt_t, const optional<T>& x) noexcept
++{
++  return (!x);
++}
++
++
++
++// 20.5.10, Comparison with T
++template <class T> constexpr bool operator==(const optional<T>& x, const T& v)
++{
++  return bool(x) ? *x == v : false;
++}
++
++template <class T> constexpr bool operator==(const T& v, const optional<T>& x)
++{
++  return bool(x) ? v == *x : false;
++}
++
++template <class T> constexpr bool operator!=(const optional<T>& x, const T& v)
++{
++  return bool(x) ? *x != v : true;
++}
++
++template <class T> constexpr bool operator!=(const T& v, const optional<T>& x)
++{
++  return bool(x) ? v != *x : true;
++}
++
++template <class T> constexpr bool operator<(const optional<T>& x, const T& v)
++{
++  return bool(x) ? *x < v : true;
++}
++
++template <class T> constexpr bool operator>(const T& v, const optional<T>& x)
++{
++  return bool(x) ? v > *x : true;
++}
++
++template <class T> constexpr bool operator>(const optional<T>& x, const T& v)
++{
++  return bool(x) ? *x > v : false;
++}
++
++template <class T> constexpr bool operator<(const T& v, const optional<T>& x)
++{
++  return bool(x) ? v < *x : false;
++}
++
++template <class T> constexpr bool operator>=(const optional<T>& x, const T& v)
++{
++  return bool(x) ? *x >= v : false;
++}
++
++template <class T> constexpr bool operator<=(const T& v, const optional<T>& x)
++{
++  return bool(x) ? v <= *x : false;
++}
++
++template <class T> constexpr bool operator<=(const optional<T>& x, const T& v)
++{
++  return bool(x) ? *x <= v : true;
++}
++
++template <class T> constexpr bool operator>=(const T& v, const optional<T>& x)
++{
++  return bool(x) ? v >= *x : true;
++}
++
++
++// Comparison of optional<T&> with T
++template <class T> constexpr bool operator==(const optional<T&>& x, const T& v)
++{
++  return bool(x) ? *x == v : false;
++}
++
++template <class T> constexpr bool operator==(const T& v, const optional<T&>& x)
++{
++  return bool(x) ? v == *x : false;
++}
++
++template <class T> constexpr bool operator!=(const optional<T&>& x, const T& v)
++{
++  return bool(x) ? *x != v : true;
++}
++
++template <class T> constexpr bool operator!=(const T& v, const optional<T&>& x)
++{
++  return bool(x) ? v != *x : true;
++}
++
++template <class T> constexpr bool operator<(const optional<T&>& x, const T& v)
++{
++  return bool(x) ? *x < v : true;
++}
++
++template <class T> constexpr bool operator>(const T& v, const optional<T&>& x)
++{
++  return bool(x) ? v > *x : true;
++}
++
++template <class T> constexpr bool operator>(const optional<T&>& x, const T& v)
++{
++  return bool(x) ? *x > v : false;
++}
++
++template <class T> constexpr bool operator<(const T& v, const optional<T&>& x)
++{
++  return bool(x) ? v < *x : false;
++}
++
++template <class T> constexpr bool operator>=(const optional<T&>& x, const T& v)
++{
++  return bool(x) ? *x >= v : false;
++}
++
++template <class T> constexpr bool operator<=(const T& v, const optional<T&>& x)
++{
++  return bool(x) ? v <= *x : false;
++}
++
++template <class T> constexpr bool operator<=(const optional<T&>& x, const T& v)
++{
++  return bool(x) ? *x <= v : true;
++}
++
++template <class T> constexpr bool operator>=(const T& v, const optional<T&>& x)
++{
++  return bool(x) ? v >= *x : true;
++}
++
++// Comparison of optional<T const&> with T
++template <class T> constexpr bool operator==(const optional<const T&>& x, const T& v)
++{
++  return bool(x) ? *x == v : false;
++}
++
++template <class T> constexpr bool operator==(const T& v, const optional<const T&>& x)
++{
++  return bool(x) ? v == *x : false;
++}
++
++template <class T> constexpr bool operator!=(const optional<const T&>& x, const T& v)
++{
++  return bool(x) ? *x != v : true;
++}
++
++template <class T> constexpr bool operator!=(const T& v, const optional<const T&>& x)
++{
++  return bool(x) ? v != *x : true;
++}
++
++template <class T> constexpr bool operator<(const optional<const T&>& x, const T& v)
++{
++  return bool(x) ? *x < v : true;
++}
++
++template <class T> constexpr bool operator>(const T& v, const optional<const T&>& x)
++{
++  return bool(x) ? v > *x : true;
++}
++
++template <class T> constexpr bool operator>(const optional<const T&>& x, const T& v)
++{
++  return bool(x) ? *x > v : false;
++}
++
++template <class T> constexpr bool operator<(const T& v, const optional<const T&>& x)
++{
++  return bool(x) ? v < *x : false;
++}
++
++template <class T> constexpr bool operator>=(const optional<const T&>& x, const T& v)
++{
++  return bool(x) ? *x >= v : false;
++}
++
++template <class T> constexpr bool operator<=(const T& v, const optional<const T&>& x)
++{
++  return bool(x) ? v <= *x : false;
++}
++
++template <class T> constexpr bool operator<=(const optional<const T&>& x, const T& v)
++{
++  return bool(x) ? *x <= v : true;
++}
++
++template <class T> constexpr bool operator>=(const T& v, const optional<const T&>& x)
++{
++  return bool(x) ? v >= *x : true;
++}
++
++
++// 20.5.12, Specialized algorithms
++template <class T>
++void swap(optional<T>& x, optional<T>& y) noexcept(noexcept(x.swap(y)))
++{
++  x.swap(y);
++}
++
++
++template <class T>
++constexpr optional<typename decay<T>::type> make_optional(T&& v)
++{
++  return optional<typename decay<T>::type>(constexpr_forward<T>(v));
++}
++
++template <class X>
++constexpr optional<X&> make_optional(reference_wrapper<X> v)
++{
++  return optional<X&>(v.get());
++}
++
++
++} // namespace experimental
++} // namespace std
++
++namespace std
++{
++  template <typename T>
++  struct hash<std::experimental::optional<T>>
++  {
++    typedef typename hash<T>::result_type result_type;
++    typedef std::experimental::optional<T> argument_type;
++    
++    constexpr result_type operator()(argument_type const& arg) const {
++      return arg ? std::hash<T>{}(*arg) : result_type{};
++    }
++  };
++  
++  template <typename T>
++  struct hash<std::experimental::optional<T&>>
++  {
++    typedef typename hash<T>::result_type result_type;
++    typedef std::experimental::optional<T&> argument_type;
++    
++    constexpr result_type operator()(argument_type const& arg) const {
++      return arg ? std::hash<T>{}(*arg) : result_type{};
++    }
++  };
++}
++
++# undef TR2_OPTIONAL_REQUIRES
++# undef TR2_OPTIONAL_ASSERTED_EXPRESSION
++
++# endif //___OPTIONAL_HPP___
++
diff --git a/deskutils/kmail/files/patch-agents_unifiedmailboxagent_utils.h b/deskutils/kmail/files/patch-agents_unifiedmailboxagent_utils.h
new file mode 100644
index 000000000000..e4c610c8ca47
--- /dev/null
+++ b/deskutils/kmail/files/patch-agents_unifiedmailboxagent_utils.h
@@ -0,0 +1,11 @@
+--- agents/unifiedmailboxagent/utils.h.orig	2018-12-29 21:15:58 UTC
++++ agents/unifiedmailboxagent/utils.h
+@@ -24,7 +24,7 @@
+ #include <QHash>
+ #include <QString>
+ 
+-#include <experimental/optional>
++#include "boost_optional.h"
+ namespace stdx {
+ // Injects content of std::experimental namespace into "exp" namespace.
+ // C++ is magical.