new
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// The -*- C++ -*- dynamic memory management header.
// Copyright (C) 1994-2018 Free Software Foundation, Inc.
// This file is part of GCC.
//
// GCC is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 3, or (at your option)
// any later version.
//
// GCC is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/** @file new
* This is a Standard C++ Library header.
*
* The header @c new defines several functions to manage dynamic memory and
* handling memory allocation errors; see
* http://gcc.gnu.org/onlinedocs/libstdc++/18_support/howto.html#4 for more.
*/
#ifndef _NEW
#define _NEW
#pragma GCC system_header
#include <bits/c++config.h>
#include <exception>
#pragma GCC visibility push(default)
extern "C++" {
namespace std
{
/**
* @brief Exception possibly thrown by @c new.
* @ingroup exceptions
*
* @c bad_alloc (or classes derived from it) is used to report allocation
* errors from the throwing forms of @c new. */
class bad_alloc : public exception
{
public:
bad_alloc() throw() { }
// This declaration is not useless:
// http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118
virtual ~bad_alloc() throw();
// See comment in eh_exception.cc.
virtual const char* what() const throw();
};
#if __cplusplus >= 201103L
class bad_array_new_length : public bad_alloc
{
public:
bad_array_new_length() throw() { }
// This declaration is not useless:
// http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118
virtual ~bad_array_new_length() throw();
// See comment in eh_exception.cc.
virtual const char* what() const throw();
};
#endif
#if __cpp_aligned_new
enum class align_val_t: size_t {};
#endif
struct nothrow_t
{
#if __cplusplus >= 201103L
explicit nothrow_t() = default;
#endif
};
extern const nothrow_t nothrow;
/** If you write your own error handler to be called by @c new, it must
* be of this type. */
typedef void (*new_handler)();
/// Takes a replacement handler as the argument, returns the
/// previous handler.
new_handler set_new_handler(new_handler) throw();
#if __cplusplus >= 201103L
/// Return the current new handler.
new_handler get_new_handler() noexcept;
#endif
} // namespace std
//@{
/** These are replaceable signatures:
* - normal single new and delete (no arguments, throw @c bad_alloc on error)
* - normal array new and delete (same)
* - @c nothrow single new and delete (take a @c nothrow argument, return
* @c NULL on error)
* - @c nothrow array new and delete (same)
*
* Placement new and delete signatures (take a memory address argument,
* does nothing) may not be replaced by a user's program.
*/
void* operator new(std::size_t) _GLIBCXX_THROW (std::bad_alloc)
__attribute__((__externally_visible__));
void* operator new[](std::size_t) _GLIBCXX_THROW (std::bad_alloc)
__attribute__((__externally_visible__));
void operator delete(void*) _GLIBCXX_USE_NOEXCEPT
__attribute__((__externally_visible__));
void operator delete[](void*) _GLIBCXX_USE_NOEXCEPT
__attribute__((__externally_visible__));
#if __cpp_sized_deallocation
void operator delete(void*, std::size_t) _GLIBCXX_USE_NOEXCEPT
__attribute__((__externally_visible__));
void operator delete[](void*, std::size_t) _GLIBCXX_USE_NOEXCEPT
__attribute__((__externally_visible__));
#endif
void* operator new(std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT
__attribute__((__externally_visible__));
void* operator new[](std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT
__attribute__((__externally_visible__));
void operator delete(void*, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT
__attribute__((__externally_visible__));
void operator delete[](void*, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT
__attribute__((__externally_visible__));
#if __cpp_aligned_new
void* operator new(std::size_t, std::align_val_t)
__attribute__((__externally_visible__));
void* operator new(std::size_t, std::align_val_t, const std::nothrow_t&)
_GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
void operator delete(void*, std::align_val_t)
_GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
void operator delete(void*, std::align_val_t, const std::nothrow_t&)
_GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
void* operator new[](std::size_t, std::align_val_t)
__attribute__((__externally_visible__));
void* operator new[](std::size_t, std::align_val_t, const std::nothrow_t&)
_GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
void operator delete[](void*, std::align_val_t)
_GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
void operator delete[](void*, std::align_val_t, const std::nothrow_t&)
_GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
#if __cpp_sized_deallocation
void operator delete(void*, std::size_t, std::align_val_t)
_GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
void operator delete[](void*, std::size_t, std::align_val_t)
_GLIBCXX_USE_NOEXCEPT __attribute__((__externally_visible__));
#endif // __cpp_sized_deallocation
#endif // __cpp_aligned_new
// Default placement versions of operator new.
inline void* operator new(std::size_t, void* __p) _GLIBCXX_USE_NOEXCEPT
{ return __p; }
inline void* operator new[](std::size_t, void* __p) _GLIBCXX_USE_NOEXCEPT
{ return __p; }
// Default placement versions of operator delete.
inline void operator delete (void*, void*) _GLIBCXX_USE_NOEXCEPT { }
inline void operator delete[](void*, void*) _GLIBCXX_USE_NOEXCEPT { }
//@}
} // extern "C++"
#if __cplusplus >= 201703L
#if __GNUC__ >= 7
# define _GLIBCXX_HAVE_BUILTIN_LAUNDER 1
#elif defined __has_builtin
// For non-GNU compilers:
# if __has_builtin(__builtin_launder)
# define _GLIBCXX_HAVE_BUILTIN_LAUNDER 1
# endif
#endif
#ifdef _GLIBCXX_HAVE_BUILTIN_LAUNDER
namespace std
{
#define __cpp_lib_launder 201606
/// Pointer optimization barrier [ptr.launder]
template<typename _Tp>
[[nodiscard]] constexpr _Tp*
launder(_Tp* __p) noexcept
{ return __builtin_launder(__p); }
// The program is ill-formed if T is a function type or
// (possibly cv-qualified) void.
template<typename _Ret, typename... _Args _GLIBCXX_NOEXCEPT_PARM>
void launder(_Ret (*)(_Args...) _GLIBCXX_NOEXCEPT_QUAL) = delete;
template<typename _Ret, typename... _Args _GLIBCXX_NOEXCEPT_PARM>
void launder(_Ret (*)(_Args......) _GLIBCXX_NOEXCEPT_QUAL) = delete;
void launder(void*) = delete;
void launder(const void*) = delete;
void launder(volatile void*) = delete;
void launder(const volatile void*) = delete;
}
#endif // _GLIBCXX_HAVE_BUILTIN_LAUNDER
#undef _GLIBCXX_HAVE_BUILTIN_LAUNDER
#endif // C++17
#pragma GCC visibility pop
#endif
std::bad_alloc::what
virtual const char * what() const
c++config.h
std::new_handler
void(* new_handler)()
Definition: new:97
std::bad_alloc
Exception possibly thrown by new.bad_alloc (or classes derived from it) is used to report allocation ...
Definition: new:54
std::get_new_handler
new_handler get_new_handler() noexcept
Return the current new handler.
std::exception
Base class for all library exceptions.
Definition: exception.h:60
exception
std
ISO C++ entities toplevel namespace is std.
std::set_new_handler
new_handler set_new_handler(new_handler)
Takes a replacement handler as the argument, returns the previous handler.