github.com/searKing/golang/go@v1.2.117/runtime/cgosymbolizer/include/boost/stacktrace/detail/void_ptr_cast.hpp (about)

     1  // Copyright 2014 Renato Tegon Forti, Antony Polukhin.
     2  // Copyright 2015-2019 Antony Polukhin.
     3  //
     4  // Distributed under the Boost Software License, Version 1.0.
     5  // (See accompanying file LICENSE_1_0.txt
     6  // or copy at http://www.boost.org/LICENSE_1_0.txt)
     7  
     8  #ifndef BOOST_STACKTRACE_DETAIL_VOID_PTR_CAST_HPP
     9  #define BOOST_STACKTRACE_DETAIL_VOID_PTR_CAST_HPP
    10  
    11  #include <boost/config.hpp>
    12  #ifdef BOOST_HAS_PRAGMA_ONCE
    13  #   pragma once
    14  #endif
    15  
    16  #include <boost/static_assert.hpp>
    17  #include <boost/type_traits/is_pointer.hpp>
    18  
    19  #if defined(__GNUC__) && defined(__GNUC_MINOR__) && (__GNUC__ * 100 + __GNUC_MINOR__ > 301)
    20  #   pragma GCC system_header
    21  #endif
    22  
    23  namespace boost { namespace stacktrace { namespace detail {
    24  
    25  // GCC warns when reinterpret_cast between function pointer and object pointer occur.
    26  // This functionsuppress the warnings and ensures that such casts are safe.
    27  template <class To, class From>
    28  To void_ptr_cast(From* v) BOOST_NOEXCEPT {
    29      BOOST_STATIC_ASSERT_MSG(
    30          boost::is_pointer<To>::value,
    31          "`void_ptr_cast` function must be used only for casting to or from void pointers."
    32      );
    33  
    34      BOOST_STATIC_ASSERT_MSG(
    35          sizeof(From*) == sizeof(To),
    36          "Pointer to function and pointer to object differ in size on your platform."
    37      );
    38  
    39      return reinterpret_cast<To>(v);
    40  }
    41  
    42  
    43  }}} // boost::stacktrace::detail
    44  
    45  #endif // BOOST_STACKTRACE_DETAIL_VOID_PTR_CAST_HPP
    46