* rand.c (random): Fix for 64 bit fixnums: stick two random numbers

together. Otherwise for fixnum moduli, we get only a 32 bit number no
matter what the modulus is.

2 files changed, 10 insertions, 0 deletions

diff --git a/ChangeLog b/ChangeLog
index 1ce4fd22..8eb46034 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,11 @@
 2011-12-22  Kaz Kylheku  <kaz@kylheku.com>
 
+	* rand.c (random): Fix for 64 bit fixnums: stick two random numbers
+	together. Otherwise for fixnum moduli, we get only a 32 bit number no
+	matter what the modulus is.
+
+2011-12-22  Kaz Kylheku  <kaz@kylheku.com>
+
 	* stream.c (vformat): Combine ~a and ~s cases, so numbers and
 	strings are printed the same way under ~s and ~a.  The only difference
 	is printing other kinds of objects.
diff --git a/rand.c b/rand.c
index 2e504514..c48ff191 100644
--- a/rand.c
+++ b/rand.c
@@ -197,7 +197,11 @@ val random(val state, val modulus)
     cnum m = c_num(modulus);
     if (m <= 0)
       goto invalid;
+#if SIZEOF_PTR >= 8
+    return num(((((cnum) rand32(r) & 0x7FFFFFFF) << 32) | rand32(r)) % m);
+#else
     return num(rand32(r) % m);
+#endif
   } 
 invalid:
   uw_throwf(numeric_error_s, lit("random: invalid modulus ~s"),