1  /* C11 threads call once implementation.
       2     Copyright (C) 2018-2023 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       4  
       5     The GNU C Library is free software; you can redistribute it and/or
       6     modify it under the terms of the GNU Lesser General Public
       7     License as published by the Free Software Foundation; either
       8     version 2.1 of the License, or (at your option) any later version.
       9  
      10     The GNU C Library is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      13     Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public
      16     License along with the GNU C Library; if not, see
      17     <https://www.gnu.org/licenses/>.  */
      18  
      19  #include <stdalign.h>
      20  #include <shlib-compat.h>
      21  
      22  #include "thrd_priv.h"
      23  
      24  void
      25  __call_once (once_flag *flag, void (*func)(void))
      26  {
      27    _Static_assert (sizeof (once_flag) == sizeof (pthread_once_t),
      28  		  "sizeof (once_flag) != sizeof (pthread_once_t)");
      29    _Static_assert (alignof (once_flag) == alignof (pthread_once_t),
      30  		  "alignof (once_flag) != alignof (pthread_once_t)");
      31    __pthread_once ((pthread_once_t *) flag, func);
      32  }
      33  #if PTHREAD_IN_LIBC
      34  versioned_symbol (libc, __call_once, call_once, GLIBC_2_34);
      35  # if OTHER_SHLIB_COMPAT (libpthread, GLIBC_2_28, GLIBC_2_34)
      36  compat_symbol (libpthread, __call_once, call_once, GLIBC_2_28);
      37  # endif
      38  #else /* !PTHREAD_IN_LIBC */
      39  strong_alias (__call_once, call_once)
      40  #endif