--- gforth/configure.in	2008/01/01 13:39:14	1.202
+++ gforth/configure.in	2008/01/02 21:04:44	1.203
@@ -120,8 +120,9 @@ else
 fi])
 
 #variables mentioned in INSTALL
-AC_ARG_VAR(CC, [The C compiler (must support GNU C 2.x); gcc-2.95 recommended.])
+AC_ARG_VAR(CC, [The C compiler (must support GNU C 2.x).])
 AC_ARG_VAR(FORTHSIZES, [Gforth command line options for the default stack and dictionary sizes (see INSTALL).])
+AC_ARG_VAR(STACK_CACHE_REGS, [number of registers in the maximum stack cache state for gforth-fast and gforth-native (default platform-dependent).])
 AC_ARG_VAR(STACK_CACHE_DEFAULT_FAST, [number of registers in the default stack cache state for gforth-fast and gforth-native (default 1).])
 AC_ARG_VAR(GCC_PR15242_WORKAROUND, [Force the enabling (1) or disabling (0) of a workaround for a gcc-3.x performance bug (default unset: use workaround for gcc-3.x)])
 
@@ -314,6 +315,9 @@ case "$host_cpu" in
 		test x$ac_cv_sizeof_long_long = x && 
 		($CC -v 2>&1 |grep -q 'gcc version 2.95') &&
 		ac_cv_sizeof_long_long=0
+                #The only architecture with enough callee-saved registers
+                test x$STACK_CACHE_REGS = x && STACK_CACHE_REGS=3
+                #or use 2, hardly slower at run-time and starts up faster
 		;;
 	*)
 		AC_MSG_WARN([Using a generic machine description])
@@ -348,6 +352,11 @@ then
 fi
 AC_SUBST(MAKEINC)
 
+AC_ARG_VAR(STACK_CACHE_REGS, [number of registers in the maximum stack cache state for gforth-fast and gforth-native (default platform-dependent).])
+
+test x$STACK_CACHE_REGS = x && STACK_CACHE_REGS=1
+AC_DEFINE_UNQUOTED(STACK_CACHE_REGS, $STACK_CACHE_REGS,
+		   [number of registers in the maximum stack cache state for gforth-fast and gforth-native])
 test x$STACK_CACHE_DEFAULT_FAST = x && STACK_CACHE_DEFAULT_FAST=1
 AC_DEFINE_UNQUOTED(STACK_CACHE_DEFAULT_FAST, $STACK_CACHE_DEFAULT_FAST,
 		   [number of registers in the default stack cache state for gforth-fast and gforth-native])