1 /* Test of once-only execution in multithreaded situations. 2 Copyright (C) 2018-2021 Free Software Foundation, Inc. 3 4 This program is free software: you can redistribute it and/or modify 5 it under the terms of the GNU General Public License as published by 6 the Free Software Foundation; either version 3 of the License, or 7 (at your option) any later version. 8 9 This program 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 15 along with this program. If not, see <https://www.gnu.org/licenses/>. */ 16 17 /* Written by Bruno Haible <bruno@clisp.org>, 2018. */ 18 19 #include <config.h> 20 21 #include <threads.h> 22 23 #include "macros.h" 24 25 static once_flag a_once = ONCE_FLAG_INIT; 26 27 static int a; 28 29 static void 30 a_init (void) /* */ 31 { 32 a = 42; 33 } 34 35 int 36 main () /* */ 37 { 38 call_once (&a_once, a_init); 39 40 ASSERT (a == 42); 41 42 return 0; 43 }