config/intdiv0.m4

   1 # intdiv0.m4 serial 1 (gettext-0.11.3)
   2 dnl Copyright (C) 2002 Free Software Foundation, Inc.
   3 dnl This file is free software, distributed under the terms of the GNU
   4 dnl General Public License.  As a special exception to the GNU General
   5 dnl Public License, this file may be distributed as part of a program
   6 dnl that contains a configuration script generated by Autoconf, under
   7 dnl the same distribution terms as the rest of that program.
   8
   9 dnl From Bruno Haible.
  10
  11 AC_DEFUN([gt_INTDIV0],
  12 [
  13   AC_REQUIRE([AC_PROG_CC])dnl
  14   AC_REQUIRE([AC_CANONICAL_HOST])dnl
  15
  16   AC_CACHE_CHECK([whether integer division by zero raises SIGFPE],
  17     gt_cv_int_divbyzero_sigfpe,
  18     [
  19       AC_TRY_RUN([
  20 #include <stdlib.h>
  21 #include <signal.h>
  22
  23 static void
  24 #ifdef __cplusplus
  25 sigfpe_handler (int sig)
  26 #else
  27 sigfpe_handler (sig) int sig;
  28 #endif
  29 {
  30   /* Exit with code 0 if SIGFPE, with code 1 if any other signal.  */
  31   exit (sig != SIGFPE);
  32 }
  33
  34 int x = 1;
  35 int y = 0;
  36 int z;
  37 int nan;
  38
  39 int main ()
  40 {
  41   signal (SIGFPE, sigfpe_handler);
  42 /* IRIX and AIX (when "xlc -qcheck" is used) yield signal SIGTRAP.  */
  43 #if (defined (__sgi) || defined (_AIX)) && defined (SIGTRAP)
  44   signal (SIGTRAP, sigfpe_handler);
  45 #endif
  46 /* Linux/SPARC yields signal SIGILL.  */
  47 #if defined (__sparc__) && defined (__linux__)
  48   signal (SIGILL, sigfpe_handler);
  49 #endif
  50
  51   z = x / y;
  52   nan = y / y;
  53   exit (1);
  54 }
  55 ], gt_cv_int_divbyzero_sigfpe=yes, gt_cv_int_divbyzero_sigfpe=no,
  56         [
  57           # Guess based on the CPU.
  58           case "$host_cpu" in
  59             alpha* | i[34567]86 | m68k | s390*)
  60               gt_cv_int_divbyzero_sigfpe="guessing yes";;
  61             *)
  62               gt_cv_int_divbyzero_sigfpe="guessing no";;
  63           esac
  64         ])
  65     ])
  66   case "$gt_cv_int_divbyzero_sigfpe" in
  67     *yes) value=1;;
  68     *) value=0;;
  69   esac
  70   AC_DEFINE_UNQUOTED(INTDIV0_RAISES_SIGFPE, $value,
  71     [Define if integer division by zero raises signal SIGFPE.])
  72 ])