diff --git a/library/bignum.c b/library/bignum.c
index a91aba8..e023afc 100644
--- a/library/bignum.c
+++ b/library/bignum.c
@@ -1105,7 +1105,7 @@
         int *ret )
 {
     size_t i;
-    unsigned int cond, done;
+    unsigned int cond, done, sign_X, sign_Y;
 
     MPI_VALIDATE_RET( X != NULL );
     MPI_VALIDATE_RET( Y != NULL );
@@ -1126,8 +1126,8 @@
      *     done = 1;
      * }
      */
-    unsigned int sign_X = X->s;
-    unsigned int sign_Y = Y->s;
+    sign_X = X->s;
+    sign_Y = Y->s;
     cond = ( ( sign_X ^ sign_Y ) >> ( sizeof( unsigned int ) * 8 - 1 ) );
     *ret = cond * X->s;
     done = cond;