tools/missing-macros/src/m4/intdiv0.m4

   1 # intdiv0.m4 serial 3 (gettext-0.18)
   2 dnl Copyright (C) 2002, 2007-2010 Free Software Foundation, Inc.
   3 dnl This file is free software; the Free Software Foundation
   4 dnl gives unlimited permission to copy and/or distribute it,
   5 dnl with or without modifications, as long as this notice is preserved.
   6
   7 dnl From Bruno Haible.
   8
   9 AC_DEFUN([gt_INTDIV0],
  10 [
  11   AC_REQUIRE([AC_PROG_CC])dnl
  12   AC_REQUIRE([AC_CANONICAL_HOST])dnl
  13
  14   AC_CACHE_CHECK([whether integer division by zero raises SIGFPE],
  15     gt_cv_int_divbyzero_sigfpe,
  16     [
  17       gt_cv_int_divbyzero_sigfpe=
  18 changequote(,)dnl
  19       case "$host_os" in
  20         macos* | darwin[6-9]* | darwin[1-9][0-9]*)
  21           # On MacOS X 10.2 or newer, just assume the same as when cross-
  22           # compiling. If we were to perform the real test, 1 Crash Report
  23           # dialog window would pop up.
  24           case "$host_cpu" in
  25             i[34567]86 | x86_64)
  26               gt_cv_int_divbyzero_sigfpe="guessing yes" ;;
  27           esac
  28           ;;
  29       esac
  30 changequote([,])dnl
  31       if test -z "$gt_cv_int_divbyzero_sigfpe"; then
  32         AC_TRY_RUN([
  33 #include <stdlib.h>
  34 #include <signal.h>
  35
  36 static void
  37 sigfpe_handler (int sig)
  38 {
  39   /* Exit with code 0 if SIGFPE, with code 1 if any other signal.  */
  40   exit (sig != SIGFPE);
  41 }
  42
  43 int x = 1;
  44 int y = 0;
  45 int z;
  46 int nan;
  47
  48 int main ()
  49 {
  50   signal (SIGFPE, sigfpe_handler);
  51 /* IRIX and AIX (when "xlc -qcheck" is used) yield signal SIGTRAP.  */
  52 #if (defined (__sgi) || defined (_AIX)) && defined (SIGTRAP)
  53   signal (SIGTRAP, sigfpe_handler);
  54 #endif
  55 /* Linux/SPARC yields signal SIGILL.  */
  56 #if defined (__sparc__) && defined (__linux__)
  57   signal (SIGILL, sigfpe_handler);
  58 #endif
  59
  60   z = x / y;
  61   nan = y / y;
  62   exit (1);
  63 }
  64 ], [gt_cv_int_divbyzero_sigfpe=yes], [gt_cv_int_divbyzero_sigfpe=no],
  65           [
  66             # Guess based on the CPU.
  67 changequote(,)dnl
  68             case "$host_cpu" in
  69               alpha* | i[34567]86 | x86_64 | m68k | s390*)
  70                 gt_cv_int_divbyzero_sigfpe="guessing yes";;
  71               *)
  72                 gt_cv_int_divbyzero_sigfpe="guessing no";;
  73             esac
  74 changequote([,])dnl
  75           ])
  76       fi
  77     ])
  78   case "$gt_cv_int_divbyzero_sigfpe" in
  79     *yes) value=1;;
  80     *) value=0;;
  81   esac
  82   AC_DEFINE_UNQUOTED([INTDIV0_RAISES_SIGFPE], [$value],
  83     [Define if integer division by zero raises signal SIGFPE.])
  84 ])