1  /* Test that setjmp/longjmp do not save and restore floating-point
       2     exceptions and rounding modes.
       3     Copyright (C) 2013-2023 Free Software Foundation, Inc.
       4     This file is part of the GNU C Library.
       5  
       6     The GNU C Library is free software; you can redistribute it and/or
       7     modify it under the terms of the GNU Lesser General Public
       8     License as published by the Free Software Foundation; either
       9     version 2.1 of the License, or (at your option) any later version.
      10  
      11     The GNU C Library is distributed in the hope that it will be useful,
      12     but WITHOUT ANY WARRANTY; without even the implied warranty of
      13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      14     Lesser General Public License for more details.
      15  
      16     You should have received a copy of the GNU Lesser General Public
      17     License along with the GNU C Library; if not, see
      18     <https://www.gnu.org/licenses/>.  */
      19  
      20  #include <fenv.h>
      21  #include <setjmp.h>
      22  #include <stdio.h>
      23  #include <stdlib.h>
      24  
      25  static jmp_buf __attribute__ ((unused)) env;
      26  static int result = 0;
      27  
      28  #if defined FE_TONEAREST && defined FE_TOWARDZERO
      29  static int expected_rounding_mode = FE_TONEAREST;
      30  
      31  static void
      32  change_rounding_mode (void)
      33  {
      34    if (fesetround (FE_TOWARDZERO) == 0)
      35      expected_rounding_mode = FE_TOWARDZERO;
      36    else
      37      puts ("fesetround (FE_TOWARDZERO) failed, continuing test");
      38    longjmp (env, 1);
      39  }
      40  #endif
      41  
      42  #ifdef FE_INVALID
      43  static int expected_exceptions = 0;
      44  
      45  static void
      46  raise_exception (void)
      47  {
      48    if (feraiseexcept (FE_INVALID) == 0)
      49      expected_exceptions = FE_INVALID;
      50    else
      51      puts ("feraiseexcept (FE_INVALID) failed, continuing test");
      52    longjmp (env, 1);
      53  }
      54  #endif
      55  
      56  static int
      57  do_test (void)
      58  {
      59  #if defined FE_TONEAREST && defined FE_TOWARDZERO
      60    if (fesetround (FE_TONEAREST) == 0)
      61      {
      62        if (setjmp (env) == 0)
      63  	change_rounding_mode ();
      64        else
      65  	{
      66  	  if (fegetround () == expected_rounding_mode)
      67  	    puts ("PASS: longjmp preserved rounding mode");
      68  	  else
      69  	    {
      70  	      puts ("FAIL: longjmp changed rounding mode");
      71  	      result = 1;
      72  	    }
      73  	}
      74      }
      75    else
      76      puts ("fesetround (FE_TONEAREST) failed, not testing rounding modes");
      77  #else
      78    puts ("rounding mode test not supported");
      79  #endif
      80  #ifdef FE_INVALID
      81    if (feclearexcept (FE_ALL_EXCEPT) == 0)
      82      {
      83        if (setjmp (env) == 0)
      84  	raise_exception ();
      85        else
      86  	{
      87  	  if (fetestexcept (FE_INVALID) == expected_exceptions)
      88  	    puts ("PASS: longjmp preserved exceptions");
      89  	  else
      90  	    {
      91  	      puts ("FAIL: longjmp changed exceptions");
      92  	      result = 1;
      93  	    }
      94  	}
      95      }
      96    else
      97      puts ("feclearexcept (FE_ALL_EXCEPT) failed, not testing exceptions");
      98  #else
      99    puts ("exception test not supported");
     100  #endif
     101    return result;
     102  }
     103  
     104  #define TEST_FUNCTION do_test ()
     105  #include "../test-skeleton.c"