From ad67424987aeae720054b21f3196471dac08f474 Mon Sep 17 00:00:00 2001
From: Nikolaj Bjorner <nbjorner@microsoft.com>
Date: Wed, 6 Jun 2018 18:23:04 -0700
Subject: [PATCH] deal with shift exponent error

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
---
 src/util/mpz.cpp | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/src/util/mpz.cpp b/src/util/mpz.cpp
index 8f65a3602..6387fccd9 100644
--- a/src/util/mpz.cpp
+++ b/src/util/mpz.cpp
@@ -79,10 +79,10 @@ unsigned u_gcd(unsigned u, unsigned v) {
     if (v == 0) return u;
     unsigned shift = _trailing_zeros32(u | v);
     u >>= _trailing_zeros32(u);
-    v >>= _trailing_zeros32(v);        
     if (u == 1 || v == 1) return 1 << shift; 
     if (u == v) return u << shift;
     do {
+        v >>= _trailing_zeros32(v);        
 #if 1
         unsigned diff = u - v;
         unsigned mdiff = diff & (unsigned)((int)diff >> 31);
@@ -113,8 +113,6 @@ unsigned u_gcd(unsigned u, unsigned v) {
         u = _bit_min(u, v);
         v = md12 | md21;
 #endif
-
-        v >>= _trailing_zeros32(v);        
     }
     while (v != 0);
     return u << shift;