libstdc++-v3/libsupc++/new_opnt.cc

// Support routines for the -*- C++ -*- dynamic memory management.
// Copyright (C) 1997-2021 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/>.

#include <bits/c++config.h>
#include <bits/exception_defines.h>
#include "new"

extern "C" void *malloc (std::size_t);

_GLIBCXX_WEAK_DEFINITION void *
operator new (std::size_t sz, const std::nothrow_t&) noexcept
{
  // _GLIBCXX_RESOLVE_LIB_DEFECTS
  // 206. operator new(size_t, nothrow) may become unlinked to ordinary
  // operator new if ordinary version replaced
  __try
    {
      return ::operator new(sz);
    }
  __catch (...)
    {
      // N.B. catch (...) means the process will terminate if operator new(sz)
      // exits with a __forced_unwind exception. The process will print
      // "FATAL: exception not rethrown" to stderr before exiting.
      //
      // If we propagated that exception the process would still terminate
      // (because this function is noexcept) but with a less informative error:
      // "terminate called without active exception".
      return nullptr;
    }
}