--- libguile/stackchk.h	12 Feb 2006 13:42:51 -0000	1.20.2.1
+++ libguile/stackchk.h	29 Jan 2008 22:16:54 -0000
@@ -37,11 +37,11 @@
 # if SCM_STACK_GROWS_UP
 #  define SCM_STACK_OVERFLOW_P(s)\
    (SCM_STACK_PTR (s) \
-    > (SCM_I_CURRENT_THREAD->base + SCM_STACK_LIMIT))
+    > (SCM_I_CURRENT_THREAD->base + ((SCM_STACK_LIMIT * sizeof(SCM)) / sizeof(SCM_STACKITEM)))
 # else
 #  define SCM_STACK_OVERFLOW_P(s)\
    (SCM_STACK_PTR (s) \
-    < (SCM_I_CURRENT_THREAD->base - SCM_STACK_LIMIT))
+    < (SCM_I_CURRENT_THREAD->base - ((SCM_STACK_LIMIT * sizeof(SCM)) / sizeof(SCM_STACKITEM))))
 # endif
 # define SCM_CHECK_STACK\
     {\