diff --git a/src/util/mpz.cpp b/src/util/mpz.cpp
index c07235ab125..bdad1ddfe8f 100644
--- a/src/util/mpz.cpp
+++ b/src/util/mpz.cpp
@@ -2248,7 +2248,10 @@ template<bool SYNCH>
 unsigned mpz_manager<SYNCH>::mlog2(mpz const & a) {
     if (is_nonneg(a))
         return 0;
-    if (is_small(a) && a.m_val > INT_MIN)
+    if (is_small(a) && a.m_val == INT_MIN)
+        return ::log2((unsigned)a.m_val);
+        
+    if (is_small(a))
         return ::log2((unsigned)-a.m_val);
 #ifndef _MP_GMP
     static_assert(sizeof(digit_t) == 8 || sizeof(digit_t) == 4, "");