guile/guile-core/libguile numbers.h

[Marius Vollmer]

CVSROOT:        /cvs
Module name:    guile
Changes by:     Marius Vollmer <address@hidden> 01/10/06 16:48:27

Modified files:
        guile-core/libguile: numbers.h 

Log message:
        Corrected definition of SCM_MOST_POSITIVE_FIXNUM.  Boy was I confused.

CVSWeb URLs:
http://savannah.gnu.org/cgi-bin/viewcvs/guile/guile-core/libguile/numbers.h.diff?cvsroot=OldCVS&tr1=1.59&tr2=1.60&r1=text&r2=text

Patches:
Index: guile/guile-core/libguile/numbers.h
diff -u guile/guile-core/libguile/numbers.h:1.59 
guile/guile-core/libguile/numbers.h:1.60
--- guile/guile-core/libguile/numbers.h:1.59    Sat Oct  6 15:58:02 2001
+++ guile/guile-core/libguile/numbers.h Sat Oct  6 16:48:27 2001
@@ -55,8 +55,13 @@
  *
  * Inums are exact integer data that fits within an SCM word.  */
 
+/* SCM_T_SIGNED_MAX is                 (- (expt 2 n) 1),
+ * SCM_MOST_POSITIVE_FIXNUM should be  (- (expt 2 (- n 2)) 1)
+ * which is the same as                (/ (- (expt 2 n) 4) 4)
+ */
+
 #define SCM_I_FIXNUM_BIT         (SCM_LONG_BIT - 2)
-#define SCM_MOST_POSITIVE_FIXNUM (SCM_T_SIGNED_BITS_MAX/8-1)
+#define SCM_MOST_POSITIVE_FIXNUM ((SCM_T_SIGNED_BITS_MAX-3)/4)
 #define SCM_MOST_NEGATIVE_FIXNUM (-SCM_MOST_POSITIVE_FIXNUM-1)
 
 /* SCM_SRS is signed right shift */
@@ -83,7 +88,7 @@
 #define SCM_INUM0 (SCM_MAKINUM (0))
 
 
-/* SCM_MAXEXP is the maximum double precision expontent
+/* SCM_MAXEXP is the maximum double precision exponent
  * SCM_FLTMAX is less than or scm_equal the largest single precision float
  */