libstdc++-v3/testsuite/20_util/assume_aligned/3.cc

   1 // Copyright (C) 2018-2022 Free Software Foundation, Inc.
   2 //
   3 // This file is part of the GNU ISO C++ Library.  This library is free
   4 // software; you can redistribute it and/or modify it under the
   5 // terms of the GNU General Public License as published by the
   6 // Free Software Foundation; either version 3, or (at your option)
   7 // any later version.
   8
   9 // This library is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13
  14 // You should have received a copy of the GNU General Public License along
  15 // with this library; see the file COPYING3.  If not see
  16 // <http://www.gnu.org/licenses/>.
  17
  18 // { dg-options "-std=gnu++2a -O2 -g0" }
  19 // { dg-do compile { target c++2a } }
  20 // { dg-final { scan-assembler-not "undefined" } }
  21
  22 #include <memory>
  23
  24 int* ptr();
  25 extern "C" void undefined();
  26
  27 void
  28 test01()
  29 {
  30   const std::size_t alignment = 4 * alignof(int);
  31   int* p = std::assume_aligned<alignment>(ptr());
  32   if ((std::uintptr_t)p % alignment)
  33     undefined();
  34 }