dnl Process this file with autoconf to produce a configure script.
AC_INIT(engine.c)

AC_ARG_ENABLE(force-reg,
[  --enable-force-reg	  Use explicit register declarations if they appear in
			  the machine.h file. This can cause a good speedup,
			  but also incorrect code with some gcc versions on
			  some processors (default disabled).],

AC_DEFINE(FORCE_REG))
dnl this is not quite according to the autoconf manual, it causes a replacement
AC_ARG_ENABLE(direct-threaded,
[  --enable-direct-threaded	Force direct threading. This may not work on
				some machines and may cause slowdown on others.
				(default processor-dependent)],
AC_DEFINE(DIRECT_THREADED))
AC_ARG_ENABLE(indirect-threaded,
[  --enable-indirect-threaded	Force indirect threading. This can cause a
				slowdown on some machines.
				(default processor-dependent)],
AC_DEFINE(INDIRECT_THREADED))

#terminology is a bit unusual here: The host is the system on which
#gforth will run; the system on which configure will run is the `build'
AC_CANONICAL_HOST
case "$host_cpu" in
	hppa*)
		mach_h=hppa
		;;
	sparc*)
		mach_h=sparc
		;;
	i386|i486|i586)
		mach_h=386
		#!! direct/indirect threading switch
		#!! -m486 flag
		;;
	m68*)
		mach_h=m68k
		;;
	mips*)
		mach_h=mips
		#!! link text and data segment into the same 256M region!
		#!! does cacheflush work on OSs other than Ultrix?
		;;
	*)
		echo "No direct threading support for $host_cpu, using indirect threading."
		echo "Using a generic 32-bit machine description. It will only work if char * AND"
		echo "long values have 32 bits."
		echo "I'll assume that C floats and doubles are represented by IEEE single and"
		echo "double numbers. If this is not so, SF@ etc. will not work correctly."
		mach_h=32bit
esac

dnl Now a little support for DOS/DJGCC
AC_SUBST(MAKE_EXE)
MAKE_EXE=""

dnl copy commands for systems that don't have links
AC_SUBST(LINK_KERNL32L)
LINK_KERNL32L=""
AC_SUBST(LINK_KERNL32B)
LINK_KERNL32B=""

#if test $host_os=dos
#then
#  echo Configuring for DOS!!!
#  MAKE_EXE="coff2exe gforth"
#  LINK_KERNL32L='$(CP) kernl32l.fi gforth.fi'
#fi

dnl the following macro produces a warning with autoconf-2.1
AC_C_BIGENDIAN
dnl ac_cv_c_bigendian is an undocumented variable of autoconf-2.1
if test $ac_cv_c_bigendian = yes; then
  bytesex=b
else
  bytesex=l
fi

dnl Checks for programs.
AC_PROG_LN_S
AC_PROG_INSTALL

dnl Checks for library functions
AC_FUNC_MEMCMP
AC_REPLACE_FUNCS(memmove strtoul)
AC_CHECK_FUNC(getopt_long,getop_long="",getopt_long="getopt.o getopt1.o")
AC_SUBST(getopt_long)
dnl This check is just for making later checks link with libm.
AC_CHECK_LIB(m,sin)
AC_CHECK_FUNCS(rint)
AC_REPLACE_FUNCS(ecvt)
dnl No check for select, because our replacement is no good under
dnl anything but DOS

dnl autoconf requires (implicitly) that AC_LINK_FILES is used only once
AC_LINK_FILES(${mach_h}.h kernl32${bytesex}.fi,machine.h gforth.fi)
AC_OUTPUT(Makefile)