m4/byteorder.m4

   1 AC_DEFUN(RFX_CHECK_BYTEORDER,
   2 [
   3 AC_MSG_CHECKING([for byte order])
   4 AC_TRY_RUN([
   5 int main (int argc, char *argv[])
   6 {
   7     int i = 1;
   8     return *(char*)&i;
   9 }
  10 ], BIGENDIAN=1, LITTLEENDIAN=1, CROSSCOMPILE=1)
  11 export CROSSCOMPILE
  12
  13 if test "x${CROSSCOMPILE}" = "x1"; then
  14  AC_MSG_RESULT(we are cross compiling- trying to guess from system type)
  15  AC_CANONICAL_SYSTEM
  16  AC_MSG_CHECKING([for byte order, try 2])
  17  case "${target}" in
  18   *86* | *-pc-* )
  19      LITTLEENDIAN=1
  20      ;;
  21   *sparc* | *68* | *88k* | *mac* | *Mac* | *sun* | *Sun* | *Amiga* | *amiga* )
  22      BIGENDIAN=1
  23      ;;
  24  esac
  25 fi
  26
  27 export LITTLEENDIAN
  28 if test "x${LITTLEENDIAN}" = "x1"; then
  29 AC_MSG_RESULT(little endian)
  30 BYTEORDERCHECKOK=1
  31 fi
  32 export BIGENDIAN
  33 if test "x${BIGENDIAN}" = "x1"; then
  34 AC_MSG_RESULT(big endian)
  35 BYTEORDERCHECKOK=1
  36 WORDS_BIGENDIAN=1
  37 export WORDS_BIGENDIAN
  38 AC_DEFINE_UNQUOTED(WORDS_BIGENDIAN, 1)
  39 fi
  40 if test "x${BYTEORDERCHECKOK}" != "x1"; then
  41 AC_MSG_RESULT(unknown)
  42 echo Byte order could not determined.
  43 exit 1
  44 fi
  45 ])
  46
  47