alignment_of.hpp
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1 
2 // (C) Copyright John Maddock 2000.
3 // Use, modification and distribution are subject to the Boost Software License,
4 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
5 // http://www.boost.org/LICENSE_1_0.txt).
6 //
7 // See http://www.boost.org/libs/type_traits for most recent version including documentation.
8 
9 #ifndef BOOST_TT_ALIGNMENT_OF_HPP_INCLUDED
10 #define BOOST_TT_ALIGNMENT_OF_HPP_INCLUDED
11 
12 #include <boost/config.hpp>
13 #include <cstddef>
14 
17 
18 #ifdef BOOST_MSVC
19 # pragma warning(push)
20 # pragma warning(disable: 4121 4512) // alignment is sensitive to packing
21 #endif
22 #if defined(__BORLANDC__) && (__BORLANDC__ < 0x600)
23 #pragma option push -Vx- -Ve-
24 #endif
25 
26 namespace boost {
27 
28 template <typename T> struct alignment_of;
29 
30 // get the alignment of some arbitrary type:
31 namespace detail {
32 
33 #ifdef BOOST_MSVC
34 #pragma warning(push)
35 #pragma warning(disable:4324) // structure was padded due to __declspec(align())
36 #endif
37 template <typename T>
39 {
40  char c;
41  T t;
43 };
44 #ifdef BOOST_MSVC
45 #pragma warning(pop)
46 #endif
47 
48 template <unsigned A, unsigned S>
50 {
51  BOOST_STATIC_CONSTANT(std::size_t, value = A < S ? A : S);
52 };
53 
54 
55 template< typename T >
57 {
58 #if defined(BOOST_MSVC) && (BOOST_MSVC >= 1400)
59  //
60  // With MSVC both the native __alignof operator
61  // and our own logic gets things wrong from time to time :-(
62  // Using a combination of the two seems to make the most of a bad job:
63  //
64  BOOST_STATIC_CONSTANT(std::size_t, value =
66  sizeof(::boost::detail::alignment_of_hack<T>) - sizeof(T),
67  __alignof(T)
68  >::value));
69 #elif !defined(BOOST_ALIGNMENT_OF)
70  BOOST_STATIC_CONSTANT(std::size_t, value =
72  sizeof(::boost::detail::alignment_of_hack<T>) - sizeof(T),
73  sizeof(T)
74  >::value));
75 #else
76  //
77  // We put this here, rather than in the definition of
78  // alignment_of below, because MSVC's __alignof doesn't
79  // always work in that context for some unexplained reason.
80  // (See type_with_alignment tests for test cases).
81  //
82  BOOST_STATIC_CONSTANT(std::size_t, value = BOOST_ALIGNMENT_OF(T));
83 #endif
84 };
85 
86 } // namespace detail
87 
88 template <class T> struct alignment_of : public integral_constant<std::size_t, ::boost::detail::alignment_of_impl<T>::value>{};
89 
90 // references have to be treated specially, assume
91 // that a reference is just a special pointer:
92 template <typename T> struct alignment_of<T&> : public alignment_of<T*>{};
93 
94 #ifdef __BORLANDC__
95 // long double gives an incorrect value of 10 (!)
96 // unless we do this...
97 struct long_double_wrapper{ long double ld; };
98 template<> struct alignment_of<long double> : public alignment_of<long_double_wrapper>{};
99 #endif
100 
101 // void has to be treated specially:
102 template<> struct alignment_of<void> : integral_constant<std::size_t, 0>{};
103 #ifndef BOOST_NO_CV_VOID_SPECIALIZATIONS
104 template<> struct alignment_of<void const> : integral_constant<std::size_t, 0>{};
105 template<> struct alignment_of<void const volatile> : integral_constant<std::size_t, 0>{};
106 template<> struct alignment_of<void volatile> : integral_constant<std::size_t, 0>{};
107 #endif
108 
109 } // namespace boost
110 
111 #if defined(__BORLANDC__) && (__BORLANDC__ < 0x600)
112 #pragma option pop
113 #endif
114 #ifdef BOOST_MSVC
115 # pragma warning(pop)
116 #endif
117 
118 #endif // BOOST_TT_ALIGNMENT_OF_HPP_INCLUDED
119 
typedef void(APIENTRY *GLDEBUGPROC)(GLenum source
BOOST_MOVE_USE_STANDARD_LIBRARY_MOVE.
GLfloat value
detail namespace with internal helper functions
Definition: json.hpp:269
#define BOOST_STATIC_CONSTANT(type, assignment)
Definition: suffix.hpp:394


librealsense2
Author(s): LibRealSense ROS Team
autogenerated on Thu Dec 22 2022 03:41:41