--- gforth/configure.in	1995/11/29 20:20:33	1.14
+++ gforth/configure.in	1995/12/11 13:15:20	1.15
@@ -1,15 +1,6 @@
 dnl Process this file with autoconf to produce a configure script.
-
 AC_INIT(engine.c)
 
-GCC=${GCC-gcc}
-AC_SUBST(GCC)
-
-dnl configure needs $CC to find out some parameters, and there may be
-dnl differences in what is obtained from gcc and from the default cc.
-dnl Therefore, we define $CC to be gcc:
-CC=$GCC
-
 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,
@@ -36,7 +27,21 @@ AC_ARG_WITH(debug,
                     debugging informations.],
 if test "$withval" = "yes"; then DEBUGFLAG=-g; fi)
 
+AC_PROG_CC
+
+if test "$GCC" = "yes"
+then
+   echo "Fine, gcc is available"
+else
+   cat <<'EOF'
+Gforth uses the GNU-C extensions for better performance. It does not work
+with other C compilers. Please install a new version of the GNU-C compiler, and
+try again.
+EOF
+   exit 1
+fi
 
+AC_SUBST(CC)
 AC_SUBST(GCCLDFLAGS)
 AC_SUBST(DEBUGFLAG)
 
@@ -54,7 +59,7 @@ case "$ac_cv_sizeof_char_p" in
 dnl    AC_CHECK_SIZEOF(long long)
 dnl    if [ $ac_cv_sizeof_long_long != 16 ]
 dnl    then
-dnl       try the whole thing with -mlonlong128
+dnl       try the whole thing with -mlonglong128
 dnl complain about C compiler and OS vendor
 dnl    fi
     ;;
@@ -75,7 +80,7 @@ case "$host_cpu" in
 		;;
 	i386|i486|i586)
 		mach_h=386
-		CFLAGS="-fforce-mem -fforce-addr -fomit-frame-pointer"
+		CFLAGS="-fomit-frame-pointer -fforce-addr -fforce-mem"
 		#!! direct/indirect threading switch
 		#!! -m486 flag
 		;;
@@ -100,6 +105,7 @@ case "$host_cpu" in
 		mach_h=32bit
 esac
 AC_SUBST(host)
+AC_SUBST(ENGINE_FLAGS)
 
 dnl Now a little support for DOS/DJGCC
 AC_SUBST(MAKE_EXE)