* bignum.c (rb_big_rshift): should properly convert the nagative

  value to 2's compliment.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@2072 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 8 insertions, 0 deletions

diff --git a/bignum.c b/bignum.c
index d59969cdd9..90a4c77012 100644
--- a/bignum.c
+++ b/bignum.c
@@ -1468,12 +1468,17 @@ rb_big_rshift(x, y)
     long j;
 
     if (shift < 0) return rb_big_lshift(x, INT2FIX(-shift));
+
     if (s1 > RBIGNUM(x)->len) {
 	if (RBIGNUM(x)->sign)
 	    return INT2FIX(0);
 	else
 	    return INT2FIX(-1);
     }
+    if (!RBIGNUM(x)->sign) {
+	x = rb_big_clone(x);
+	rb_big_2comp(x);
+    }
     xds = BDIGITS(x);
     i = RBIGNUM(x)->len; j = i - s1;
     z = bignew(j, RBIGNUM(x)->sign);
@@ -1483,6 +1488,9 @@ rb_big_rshift(x, y)
 	zds[j] = BIGLO(num);
 	num = BIGUP(xds[i]);
     }
+    if (!RBIGNUM(x)->sign) {
+	rb_big_2comp(z);
+    }
     return bignorm(z);
 }