From a7f33f5d6fe4d4c62f5e0364595131a591a7d4ac Mon Sep 17 00:00:00 2001
From: Andrzej Krzemienski <akrzemi1@gmail.com>
Date: Tue, 31 Oct 2017 02:47:13 +0100
Subject: [PATCH] more defensive checking for trivial types -- avoiding bugs

---
 .../boost/optional/detail/optional_config.hpp | 29 ++++++++++++++++++-
 include/boost/optional/optional.hpp           | 12 ++++++--
 test/optional_test_static_properties.cpp      | 25 ++++++++--------
 3 files changed, 50 insertions(+), 16 deletions(-)

diff --git a/include/boost/optional/detail/optional_config.hpp b/include/boost/optional/detail/optional_config.hpp
index d5d3514..6bb411c 100644
--- a/include/boost/optional/detail/optional_config.hpp
+++ b/include/boost/optional/detail/optional_config.hpp
@@ -1,5 +1,5 @@
 // Copyright (C) 2003, 2008 Fernando Luis Cacciola Carballal.
-// Copyright (C) 2015 Andrzej Krzemienski.
+// Copyright (C) 2015 - 2017 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
@@ -15,6 +15,7 @@
 
 #include <boost/config.hpp>
 #include <boost/detail/workaround.hpp>
+#include <boost/type_traits/intrinsics.hpp>
 
 #if (defined BOOST_NO_CXX11_RVALUE_REFERENCES) || (defined BOOST_OPTIONAL_CONFIG_NO_RVALUE_REFERENCES)
 # define BOOST_OPTIONAL_DETAIL_NO_RVALUE_REFERENCES
@@ -124,4 +125,30 @@
 # define BOOST_OPTIONAL_DETAIL_NO_DEFAULTED_FUNCTIONS
 #endif
 
+
+// The condition to use POD implementation
+
+#ifdef BOOST_OPTIONAL_CONFIG_NO_POD_SPEC
+# define BOOST_OPTIONAL_DETAIL_NO_SPEC_FOR_TRIVIAL_TYPES
+#elif defined BOOST_OPTIONAL_CONFIG_NO_SPEC_FOR_TRIVIAL_TYPES
+# define BOOST_OPTIONAL_DETAIL_NO_SPEC_FOR_TRIVIAL_TYPES
+#elif !defined BOOST_HAS_TRIVIAL_CONSTRUCTOR
+# define BOOST_OPTIONAL_DETAIL_NO_SPEC_FOR_TRIVIAL_TYPES
+#elif !defined BOOST_HAS_TRIVIAL_MOVE_ASSIGN
+# define BOOST_OPTIONAL_DETAIL_NO_SPEC_FOR_TRIVIAL_TYPES
+#elif !defined BOOST_HAS_TRIVIAL_MOVE_CONSTRUCTOR
+# define BOOST_OPTIONAL_DETAIL_NO_SPEC_FOR_TRIVIAL_TYPES
+#elif !defined BOOST_HAS_TRIVIAL_COPY
+# define BOOST_OPTIONAL_DETAIL_NO_SPEC_FOR_TRIVIAL_TYPES
+#elif !defined BOOST_HAS_TRIVIAL_ASSIGN
+# define BOOST_OPTIONAL_DETAIL_NO_SPEC_FOR_TRIVIAL_TYPES
+#elif !defined BOOST_HAS_TRIVIAL_DESTRUCTOR
+# define BOOST_OPTIONAL_DETAIL_NO_SPEC_FOR_TRIVIAL_TYPES
+#endif
+
+#ifdef BOOST_OPTIONAL_CONFIG_NO_POD_SPEC
+# define BOOST_OPTIONAL_DETAIL_NO_POD_SPEC
+#endif
+
+
 #endif // header guard
diff --git a/include/boost/optional/optional.hpp b/include/boost/optional/optional.hpp
index 6d5a5a7..4a237a1 100644
--- a/include/boost/optional/optional.hpp
+++ b/include/boost/optional/optional.hpp
@@ -806,6 +806,7 @@ struct is_optional_val_init_candidate
 {};
 
 
+#ifndef BOOST_OPTIONAL_DETAIL_NO_SPEC_FOR_TRIVIAL_TYPES
 template <typename T>
 struct is_type_trivially_copyable
   : boost::conditional<(boost::has_trivial_copy_constructor<T>::value &&
@@ -815,6 +816,13 @@ struct is_type_trivially_copyable
                         boost::has_trivial_assign<T>::value),
                         boost::true_type, boost::false_type>::type
 {};
+#else
+template <typename T>
+struct is_type_trivially_copyable
+: boost::conditional<(boost::is_scalar<T>::value && !boost::is_const<T>::value && !boost::is_volatile<T>::value),
+                     boost::true_type, boost::false_type>::type
+{};
+#endif
 
 } // namespace optional_detail
 
@@ -822,7 +830,7 @@ namespace optional_config {
   
 template <typename T>
 struct is_type_trivial
-  : boost::conditional< (optional_detail::is_type_trivially_copyable<T>::value && boost::has_trivial_default_constructor<T>::value) ||
+  : boost::conditional< (optional_detail::is_type_trivially_copyable<T>::value && BOOST_HAS_TRIVIAL_CONSTRUCTOR(T)) ||
                         (boost::is_scalar<T>::value && !boost::is_const<T>::value && !boost::is_volatile<T>::value)
                       , boost::true_type, boost::false_type>::type
 {};
@@ -830,7 +838,7 @@ struct is_type_trivial
 } // namespace optional_config
 
 
-#ifndef BOOST_OPTIONAL_CONFIG_NO_SPEC_FOR_TRIVIAL_TYPES
+#ifndef BOOST_OPTIONAL_DETAIL_NO_POD_SPEC
 #  define BOOST_OPTIONAL_BASE_TYPE(T) boost::conditional< optional_config::is_type_trivial<T>::value, \
                                       optional_detail::tc_optional_base<T>, \
                                       optional_detail::optional_base<T> \
diff --git a/test/optional_test_static_properties.cpp b/test/optional_test_static_properties.cpp
index 02c1af6..d9a0b69 100644
--- a/test/optional_test_static_properties.cpp
+++ b/test/optional_test_static_properties.cpp
@@ -19,12 +19,7 @@
 #include "boost/core/lightweight_test_trait.hpp"
 #include "boost/type_traits/is_base_of.hpp"
 
-#ifndef BOOST_NO_CXX11_DEFAULTED_FUNCTIONS
-
-#if (defined BOOST_HAS_TRIVIAL_MOVE_ASSIGN) && (defined BOOST_HAS_TRIVIAL_MOVE_CONSTRUCTOR) && (defined BOOST_HAS_TRIVIAL_CONSTRUCTOR) && (defined BOOST_HAS_TRIVIAL_COPY) && (defined BOOST_HAS_TRIVIAL_ASSIGN) && (defined BOOST_HAS_TRIVIAL_DESTRUCTOR)
-#else
-#  define BOOST_OPTIONAL_NO_TRIVIALITY_DETECTION
-#endif
+#ifndef BOOST_OPTIONAL_DETAIL_NO_DEFAULTED_FUNCTIONS
 
 struct PrivDefault
 {
@@ -77,9 +72,7 @@ void test_type_traits()
   // this only tests if type traits are implemented correctly
   BOOST_TEST_TRAIT_TRUE(( boost::optional_config::is_type_trivial<int> ));
   BOOST_TEST_TRAIT_TRUE(( boost::optional_config::is_type_trivial<double> ));
-  BOOST_TEST_TRAIT_TRUE(( boost::optional_config::is_type_trivial<Empty> ));
-  BOOST_TEST_TRAIT_TRUE(( boost::optional_config::is_type_trivial<Aggregate<int, double> > ));
-  BOOST_TEST_TRAIT_TRUE(( boost::optional_config::is_type_trivial<Aggregate<Aggregate<Empty, int>, double> > ));
+
   
   BOOST_TEST_TRAIT_TRUE(( boost::optional_config::is_type_trivial<CustomizedTrivial> ));
   
@@ -95,11 +88,17 @@ void test_type_traits()
   
   BOOST_TEST_TRAIT_TRUE(( boost::optional_detail::is_type_trivially_copyable<int> ));
   BOOST_TEST_TRAIT_TRUE(( boost::optional_detail::is_type_trivially_copyable<double> ));
+
+ 
+#ifndef BOOST_OPTIONAL_DETAIL_NO_SPEC_FOR_TRIVIAL_TYPES
+  BOOST_TEST_TRAIT_TRUE(( boost::optional_config::is_type_trivial<Empty> ));
+  BOOST_TEST_TRAIT_TRUE(( boost::optional_config::is_type_trivial<Aggregate<int, double> > ));
+  BOOST_TEST_TRAIT_TRUE(( boost::optional_config::is_type_trivial<Aggregate<Aggregate<Empty, int>, double> > ));
+  
   BOOST_TEST_TRAIT_TRUE(( boost::optional_detail::is_type_trivially_copyable<Empty> ));
   BOOST_TEST_TRAIT_TRUE(( boost::optional_detail::is_type_trivially_copyable<Aggregate<int, double> > ));
   BOOST_TEST_TRAIT_TRUE(( boost::optional_detail::is_type_trivially_copyable<Aggregate<Aggregate<Empty, int>, double> > ));
- 
-#ifndef BOOST_OPTIONAL_NO_TRIVIALITY_DETECTION
+  
   BOOST_TEST_TRAIT_TRUE(( boost::optional_detail::is_type_trivially_copyable<PrivDefault> ));
   BOOST_TEST_TRAIT_TRUE(( boost::optional_detail::is_type_trivially_copyable<NoDefault> ));
   BOOST_TEST_TRAIT_TRUE(( boost::optional_detail::is_type_trivially_copyable<CustDefault> ));
@@ -118,7 +117,7 @@ void test_trivial_copyability()
   BOOST_TEST_TRAIT_TRUE((boost::is_base_of<boost::optional_detail::tc_optional_base<double>, boost::optional<double> > ));
   BOOST_TEST_TRAIT_TRUE((boost::is_base_of<boost::optional_detail::tc_optional_base<CustomizedTrivial>, boost::optional<CustomizedTrivial> > ));
   
-#ifndef BOOST_OPTIONAL_NO_TRIVIALITY_DETECTION
+#ifndef BOOST_OPTIONAL_DETAIL_NO_SPEC_FOR_TRIVIAL_TYPES
   BOOST_TEST_TRAIT_TRUE(( boost::optional_detail::is_type_trivially_copyable<boost::optional<int> > ));
   BOOST_TEST_TRAIT_TRUE(( boost::optional_detail::is_type_trivially_copyable<boost::optional<double> > ));
   BOOST_TEST_TRAIT_TRUE(( boost::optional_detail::is_type_trivially_copyable<boost::optional<CustomizedTrivial> > ));
@@ -132,7 +131,7 @@ void test_trivial_copyability()
 
 int main()
 {
-#ifndef BOOST_NO_CXX11_DEFAULTED_FUNCTIONS
+#ifndef BOOST_OPTIONAL_DETAIL_NO_DEFAULTED_FUNCTIONS
   test_type_traits();
   test_trivial_copyability();
 #endif