* bignum.c (rb_big_neg): may be accessing bogus pointer value.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@8694 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 4 insertions, 2 deletions

diff --git a/bignum.c b/bignum.c
index f1d26ffd8a..c5154dbe13 100644
--- a/bignum.c
+++ b/bignum.c
@@ -1055,10 +1055,12 @@ rb_big_neg(x)
     VALUE x;
 {
     VALUE z = rb_big_clone(x);
-    BDIGIT *ds = BDIGITS(z);
-    long i = RBIGNUM(x)->len;
+    BDIGIT *ds;
+    long i;
 
     if (!RBIGNUM(x)->sign) get2comp(z);
+    ds = BDIGITS(z);
+    i = RBIGNUM(x)->len;
     while (i--) {
 	ds[i] = ~ds[i];
     }