m4/intdiv0.m4

   1 # intdiv0.m4 serial 6 (gettext-0.18.2)
   2 dnl Copyright (C) 2002, 2007-2008, 2010-2019 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 "$host_os" in
  20         macos* | darwin[6-9]* | darwin[1-9][0-9]*)
  21           # On Mac OS X 10.2 or newer, just assume the same as when cross-
  22           # compiling. If we were to perform the real test, 1 Crash Report
  23           # dialog window would pop up.
  24           case "$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 "$gt_cv_int_divbyzero_sigfpe"; then
  32         AC_RUN_IFELSE(
  33           [AC_LANG_SOURCE([[
  34 #include <stdlib.h>
  35 #include <signal.h>
  36
  37 static void
  38 sigfpe_handler (int sig)
  39 {
  40   /* Exit with code 0 if SIGFPE, with code 1 if any other signal.  */
  41   exit (sig != SIGFPE);
  42 }
  43
  44 int x = 1;
  45 int y = 0;
  46 int z;
  47 int xnan;
  48
  49 int main ()
  50 {
  51   signal (SIGFPE, sigfpe_handler);
  52 /* IRIX and AIX (when "xlc -qcheck" is used) yield signal SIGTRAP.  */
  53 #if (defined (__sgi) || defined (_AIX)) && defined (SIGTRAP)
  54   signal (SIGTRAP, sigfpe_handler);
  55 #endif
  56 /* Linux/SPARC yields signal SIGILL.  */
  57 #if defined (__sparc__) && defined (__linux__)
  58   signal (SIGILL, sigfpe_handler);
  59 #endif
  60
  61   z = x / y;
  62   xnan = y / y;
  63   exit (2);
  64 }
  65 ]])],
  66           [gt_cv_int_divbyzero_sigfpe=yes],
  67           [gt_cv_int_divbyzero_sigfpe=no],
  68           [
  69             # Guess based on the CPU.
  70 changequote(,)dnl
  71             case "$host_cpu" in
  72               alpha* | i[34567]86 | x86_64 | m68k | s390*)
  73                 gt_cv_int_divbyzero_sigfpe="guessing yes";;
  74               *)
  75                 gt_cv_int_divbyzero_sigfpe="guessing no";;
  76             esac
  77 changequote([,])dnl
  78           ])
  79       fi
  80     ])
  81   case "$gt_cv_int_divbyzero_sigfpe" in
  82     *yes) value=1;;
  83     *) value=0;;
  84   esac
  85   AC_DEFINE_UNQUOTED([INTDIV0_RAISES_SIGFPE], [$value],
  86     [Define if integer division by zero raises signal SIGFPE.])
  87 ])