tests/test-fenv-except-tracking-3.c

   1 /* Test of tracking of floating-point exceptions.
   2    Copyright (C) 2023-2025 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>, 2023.  */
  18
  19 #include <config.h>
  20
  21 /* Specification.  */
  22 #include <fenv.h>
  23
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27
  28 #include "macros.h"
  29
  30 /* musl libc does not support floating-point exception trapping, even where
  31    the hardware supports it.  See
  32    <https://wiki.musl-libc.org/functional-differences-from-glibc.html>  */
  33 #if !MUSL_LIBC || GNULIB_FEENABLEEXCEPT
  34
  35 /* Check that feraiseexcept() can trigger a trap.  */
  36
  37 int
  38 main (int argc, char *argv[])
  39 {
  40   if (argc > 1)
  41     {
  42       int exception;
  43
  44       if (STREQ (argv[1], "FE_INVALID"))   exception = FE_INVALID;   else
  45       if (STREQ (argv[1], "FE_DIVBYZERO")) exception = FE_DIVBYZERO; else
  46       if (STREQ (argv[1], "FE_OVERFLOW"))  exception = FE_OVERFLOW;  else
  47       if (STREQ (argv[1], "FE_UNDERFLOW")) exception = FE_UNDERFLOW; else
  48       if (STREQ (argv[1], "FE_INEXACT"))   exception = FE_INEXACT;   else
  49         {
  50           printf ("Invalid argument: %s\n", argv[1]);
  51           exit (1);
  52         }
  53
  54       /* Clear FE_XX exceptions from past operations.  */
  55       feclearexcept (exception);
  56
  57       /* An FE_XX exception shall trigger a SIGFPE signal, which by default
  58          terminates the program.  */
  59       if (feenableexcept (exception) == -1)
  60         {
  61           fputs ("Skipping test: trapping floating-point exceptions are not supported on this machine.\n", stderr);
  62           return 77;
  63         }
  64
  65       feraiseexcept (exception);
  66     }
  67
  68   return test_exit_status;
  69 }
  70
  71 #else
  72
  73 int
  74 main ()
  75 {
  76   fputs ("Skipping test: feenableexcept not available\n", stderr);
  77   return 77;
  78 }
  79
  80 #endif